ML Algorithms usually solve an optimization problem such that we need to find parameters for a given model that minimizes
— Loss function (prediction error)
— Model simplicity (regularization)
This document provides an introduction to machine learning concepts including regression analysis, similarity and metric learning, Bayes classifiers, clustering, and neural networks. It discusses techniques such as linear regression, K-means clustering, naive Bayes classification, and backpropagation in neural networks. Code examples and exercises are provided to help readers learn how to apply these machine learning algorithms.
This document provides an introduction to machine learning concepts including supervised and unsupervised learning. It discusses linear regression with one variable and multiple variables. For linear regression with one variable, it describes the hypothesis function, cost function, gradient descent algorithm, and makes predictions using a housing dataset. For multiple variables, it introduces feature normalization and applies the concepts to predict housing prices based on size, bedrooms and price in a real estate dataset. The document provides code examples to implement the algorithms.
This slide gives brief overview of supervised, unsupervised and reinforcement learning. Algorithms discussed are Naive Bayes, K nearest neighbour, SVM,decision tree, Markov model.
Difference between regression and classification. difference between supervised and reinforcement, iterative functioning of Markov model and machine learning applications.
- The document discusses a lecture on machine learning given by Ravi Gupta and G. Bharadwaja Kumar.
- Machine learning allows computers to automatically improve at tasks through experience. It is used for problems where the output is unknown and computation is expensive.
- Machine learning involves training a decision function or hypothesis on examples to perform tasks like classification, regression, and clustering. The training experience and representation impact whether learning succeeds.
- Choosing how to represent the target function, select training examples, and update weights to improve performance are issues in machine learning systems.
The document discusses recommender systems and sequential recommendation problems. It covers several key points:
1) Matrix factorization and collaborative filtering techniques are commonly used to build recommender systems, but have limitations like cold start problems and how to incorporate additional constraints.
2) Sequential recommendation problems can be framed as multi-armed bandit problems, where past recommendations influence future recommendations.
3) Various bandit algorithms like UCB, Thompson sampling, and LinUCB can be applied, but extending guarantees to models like matrix factorization is challenging. Offline evaluation on real-world datasets is important.
The document discusses decision tree learning, which is a machine learning approach for classification that builds classification models in the form of a decision tree. It describes the ID3 algorithm, which is a popular method for generating a decision tree from a set of training data. The ID3 algorithm uses information gain as the splitting criterion to recursively split the training data into purer subsets based on the values of the attributes. It selects the attribute with the highest information gain to make decisions at each node in the tree. Entropy from information theory is used to measure the information gain, with the goal being to build a tree that best classifies the training instances into target classes. An example applying the ID3 algorithm to a tennis playing dataset is provided to illustrate
Mathematical Background for Artificial Intelligenceananth
Mathematical background is essential for understanding and developing AI and Machine Learning applications. In this presentation we give a brief tutorial that encompasses basic probability theory, distributions, mixture models, anomaly detection, graphical representations such as Bayesian Networks, etc.
Introdution and designing a learning systemswapnac12
The document discusses machine learning and provides definitions and examples. It covers the following key points:
- Machine learning is a subfield of artificial intelligence concerned with developing algorithms that allow computers to learn from data without being explicitly programmed.
- Well-posed learning problems have a defined task, performance measure, and training experience. Examples given include learning to play checkers and recognize handwritten words.
- Designing a machine learning system involves choosing a training experience, target function, representation of the target function, and learning algorithm to approximate the function. A checkers-playing example is used to illustrate these design decisions.
The document discusses concepts related to supervised machine learning and decision tree algorithms. It defines key terms like supervised vs unsupervised learning, concept learning, inductive bias, and information gain. It also describes the basic process for learning decision trees, including selecting the best attribute at each node using information gain to create a small tree that correctly classifies examples, and evaluating performance on test data. Extensions like handling real-valued, missing and noisy data, generating rules from trees, and pruning trees to avoid overfitting are also covered.
This document provides an overview of classification in machine learning. It discusses supervised learning and the classification process. It describes several common classification algorithms including k-nearest neighbors, Naive Bayes, decision trees, and support vector machines. It also covers performance evaluation metrics like accuracy, precision and recall. The document uses examples to illustrate classification tasks and the training and testing process in supervised learning.
This document provides an overview of advanced data structures and algorithm analysis taught by Dr. Sukhamay Kundu at Louisiana State University. It discusses the role of data structures in making computations faster by supporting efficient data access and storage. The document distinguishes between algorithms, which determine the computational steps and data access order, and data structures, which enable efficient reading and writing of data. It also describes different methods for measuring algorithm performance, such as theoretical time complexity analysis and empirical measurements. Examples are provided for instrumenting code to count operations. Overall, the document introduces fundamental concepts about algorithms and data structures.
1) The document discusses various methods for interpreting machine learning models, including global and local surrogate models, feature importance plots, Shapley values, partial dependence plots, and individual conditional expectation plots.
2) It explains that interpretability refers to how understandable the reasons for a model's predictions are to humans. Interpretability methods can provide global explanations of entire models or local explanations of individual predictions.
3) The document advocates that improving interpretability is important for addressing issues like bias in machine learning systems and increasing trust in applications used for high-stakes decisions like criminal justice.
Machine learning is the science of getting computers to act without being explicitly programmed. In the past decade, machine learning has given us self-driving cars, practical speech recognition, effective web search, and a vastly improved understanding of the human genome. Machine learning is so pervasive today that you probably use it dozens of times a day without knowing it.
We will review some modern machine learning applications, understand variety of machine learning problem definitions, go through particular approaches of solving machine learning tasks.
This year 2015 Amazon and Microsoft introduced services to perform machine learning tasks in cloud. Microsoft Azure Machine Learning offers a streamlined experience for all data scientist skill levels, from setting up with only a web browser, to using drag and drop gestures and simple data flow graphs to set up experiments.
We will briefly review Azure ML Studio features and run machine learning experiment.
In this presentation we describe the formulation of the HMM model as consisting of states that are hidden that generate the observables. We introduce the 3 basic problems: Finding the probability of a sequence of observation given the model, the decoding problem of finding the hidden states given the observations and the model and the training problem of determining the model parameters that generate the given observations. We discuss the Forward, Backward, Viterbi and Forward-Backward algorithms.
The document discusses machine learning and various related concepts. It provides an overview of machine learning, including well-posed learning problems, designing learning systems, supervised learning, and different machine learning approaches. It also discusses specific machine learning algorithms like naive Bayes classification and decision tree learning.
Generative Adversarial Networks : Basic architecture and variantsananth
In this presentation we review the fundamentals behind GANs and look at different variants. We quickly review the theory such as the cost functions, training procedure, challenges and go on to look at variants such as CycleGAN, SAGAN etc.
Machine learning concepts and techniques are summarized in three paragraphs. Key points include:
Learning allows systems to perform tasks more efficiently over time by modifying representations based on experiences. Major learning paradigms include supervised learning from labeled examples, unsupervised learning like clustering without labels, and reinforcement learning using feedback/rewards.
Decision trees are a common inductive learning approach that extrapolate patterns from training examples to classify new examples. They are built top-down by selecting attributes that best split examples into homogeneous groups. The attribute with highest information gain is selected at each node.
Decision trees may be evaluated on predictive accuracy and pruned to avoid overfitting. Rules can be extracted from trees' paths. Parameters are set using
The document discusses function approximation and pattern recognition using neural networks. It introduces concepts like the perceptron, multi-layer perceptrons, backpropagation algorithm, supervised and unsupervised learning. It provides examples of using neural networks for function approximation and pattern recognition problems. Matlab code is also presented to illustrate training a neural network on sample datasets.
Dictionary Learning for Massive Matrix Factorizationrecsysfr
The document presents a new algorithm called Subsampled Online Dictionary Learning (SODL) for solving very large matrix factorization problems with missing values efficiently. SODL adapts an existing online dictionary learning algorithm to handle missing values by only using the known ratings for each user, allowing it to process large datasets with billions of ratings in linear time with respect to the number of known ratings. Experiments on movie rating datasets show that SODL achieves similar prediction accuracy as the fastest existing solver but with a speed up of up to 6.8 times on the largest Netflix dataset tested.
Uncertainty Awareness in Integrating Machine Learning and Game TheoryRikiya Takahashi
This document discusses integrating machine learning and game theory while accounting for uncertainty. It provides an example of previous work predicting travel time distribution on a road network using taxi data. It also discusses functional approximation in reinforcement learning, noting that techniques like deep learning can better represent functions with fewer parameters compared to nonparametric models like random forests. The document emphasizes avoiding unnecessary intermediate estimation steps and using approaches like fitted Q-iteration that are robust to estimation errors from small datasets.
This document discusses decision trees and the ID3 algorithm for generating decision trees. It explains that a decision tree classifies examples based on their attributes through a series of questions or rules. The ID3 algorithm uses information gain to choose the most informative attributes to split on at each node, resulting in a tree that maximizes classification accuracy. Some drawbacks of decision trees are that they can only handle nominal attributes and may not be robust to noisy data.
Machine Learning : why we should know and how it worksKevin Lee
This document provides an overview of machine learning, including:
- An introduction to machine learning and why it is important.
- The main types of machine learning algorithms: supervised learning, unsupervised learning, and deep neural networks.
- Examples of how machine learning algorithms work, such as logistic regression, support vector machines, and k-means clustering.
- How machine learning is being applied in various industries like healthcare, commerce, and more.
This document describes a statistical framework for interactive image category search based on mental matching. The framework allows a user to search an unstructured image database for a target category that exists only as a "mental picture" by providing feedback on displayed image sets. At each iteration, the system selects images to maximize the information gained from the user's response. The goal is to minimize the number of iterations needed to display an image from the target category. Experiments showed the approach was effective on databases containing tens of thousands of images across several semantic categories.
This document provides an overview of machine learning techniques for text mining and information extraction, including supervised, unsupervised, and weakly supervised learning algorithms. It discusses support vector machines, naive Bayes models, maximum entropy models, and feature selection methods. Key machine learning approaches covered are support vector machines, naive Bayes classifiers, maximum entropy models, and the use of kernels and feature extraction for text classification tasks.
This document provides an overview of machine learning techniques using R. It discusses regression, classification, linear models, decision trees, neural networks, genetic algorithms, support vector machines, and ensembling methods. Evaluation metrics and algorithms like lm(), rpart(), nnet(), ksvm(), and ga() are presented for different machine learning tasks. The document also compares inductive learning, analytical learning, and explanation-based learning approaches.
Regularization and feature selection techniques can help prevent overfitting in machine learning models. Regularization adds a penalty term to the cost function that shrinks coefficient magnitudes, while feature selection aims to identify and remove unnecessary features. Both approaches reduce model complexity to improve generalization. Ridge regression performs L2 regularization by adding a penalty term that shrinks all coefficients. Lasso regression uses L1 regularization to drive some coefficients to exactly zero, performing embedded feature selection. Elastic net is a compromise that allows for both L1 and L2 regularization. Recursive feature elimination (RFE) removes features, using a model to recursively eliminate the weakest features.
Total productive maintenance (TPM) is a system for maintaining equipment and processes to maximize productivity. It focuses on preventing breakdowns and delays. The main objectives of TPM are to increase productivity with modest maintenance investments and improve overall equipment effectiveness. TPM addresses the causes of accelerated equipment deterioration while promoting collaboration between operators and equipment to increase ownership. It employs eight pillars like planned maintenance and autonomous maintenance to proactively improve reliability.
Saleh Hijjah is a Jordanian national currently residing in Riyadh, Saudi Arabia. He received a diploma in Management Information Systems in 2010 from the Arabic College in Jordan. He has worked for Taj Seebal Construction Co. since 2011, where his responsibilities include administrative affairs, human resources, and office services. He is proficient in Microsoft Office, ERP systems, and both Arabic and English.
Introdution and designing a learning systemswapnac12
The document discusses machine learning and provides definitions and examples. It covers the following key points:
- Machine learning is a subfield of artificial intelligence concerned with developing algorithms that allow computers to learn from data without being explicitly programmed.
- Well-posed learning problems have a defined task, performance measure, and training experience. Examples given include learning to play checkers and recognize handwritten words.
- Designing a machine learning system involves choosing a training experience, target function, representation of the target function, and learning algorithm to approximate the function. A checkers-playing example is used to illustrate these design decisions.
The document discusses concepts related to supervised machine learning and decision tree algorithms. It defines key terms like supervised vs unsupervised learning, concept learning, inductive bias, and information gain. It also describes the basic process for learning decision trees, including selecting the best attribute at each node using information gain to create a small tree that correctly classifies examples, and evaluating performance on test data. Extensions like handling real-valued, missing and noisy data, generating rules from trees, and pruning trees to avoid overfitting are also covered.
This document provides an overview of classification in machine learning. It discusses supervised learning and the classification process. It describes several common classification algorithms including k-nearest neighbors, Naive Bayes, decision trees, and support vector machines. It also covers performance evaluation metrics like accuracy, precision and recall. The document uses examples to illustrate classification tasks and the training and testing process in supervised learning.
This document provides an overview of advanced data structures and algorithm analysis taught by Dr. Sukhamay Kundu at Louisiana State University. It discusses the role of data structures in making computations faster by supporting efficient data access and storage. The document distinguishes between algorithms, which determine the computational steps and data access order, and data structures, which enable efficient reading and writing of data. It also describes different methods for measuring algorithm performance, such as theoretical time complexity analysis and empirical measurements. Examples are provided for instrumenting code to count operations. Overall, the document introduces fundamental concepts about algorithms and data structures.
1) The document discusses various methods for interpreting machine learning models, including global and local surrogate models, feature importance plots, Shapley values, partial dependence plots, and individual conditional expectation plots.
2) It explains that interpretability refers to how understandable the reasons for a model's predictions are to humans. Interpretability methods can provide global explanations of entire models or local explanations of individual predictions.
3) The document advocates that improving interpretability is important for addressing issues like bias in machine learning systems and increasing trust in applications used for high-stakes decisions like criminal justice.
Machine learning is the science of getting computers to act without being explicitly programmed. In the past decade, machine learning has given us self-driving cars, practical speech recognition, effective web search, and a vastly improved understanding of the human genome. Machine learning is so pervasive today that you probably use it dozens of times a day without knowing it.
We will review some modern machine learning applications, understand variety of machine learning problem definitions, go through particular approaches of solving machine learning tasks.
This year 2015 Amazon and Microsoft introduced services to perform machine learning tasks in cloud. Microsoft Azure Machine Learning offers a streamlined experience for all data scientist skill levels, from setting up with only a web browser, to using drag and drop gestures and simple data flow graphs to set up experiments.
We will briefly review Azure ML Studio features and run machine learning experiment.
In this presentation we describe the formulation of the HMM model as consisting of states that are hidden that generate the observables. We introduce the 3 basic problems: Finding the probability of a sequence of observation given the model, the decoding problem of finding the hidden states given the observations and the model and the training problem of determining the model parameters that generate the given observations. We discuss the Forward, Backward, Viterbi and Forward-Backward algorithms.
The document discusses machine learning and various related concepts. It provides an overview of machine learning, including well-posed learning problems, designing learning systems, supervised learning, and different machine learning approaches. It also discusses specific machine learning algorithms like naive Bayes classification and decision tree learning.
Generative Adversarial Networks : Basic architecture and variantsananth
In this presentation we review the fundamentals behind GANs and look at different variants. We quickly review the theory such as the cost functions, training procedure, challenges and go on to look at variants such as CycleGAN, SAGAN etc.
Machine learning concepts and techniques are summarized in three paragraphs. Key points include:
Learning allows systems to perform tasks more efficiently over time by modifying representations based on experiences. Major learning paradigms include supervised learning from labeled examples, unsupervised learning like clustering without labels, and reinforcement learning using feedback/rewards.
Decision trees are a common inductive learning approach that extrapolate patterns from training examples to classify new examples. They are built top-down by selecting attributes that best split examples into homogeneous groups. The attribute with highest information gain is selected at each node.
Decision trees may be evaluated on predictive accuracy and pruned to avoid overfitting. Rules can be extracted from trees' paths. Parameters are set using
The document discusses function approximation and pattern recognition using neural networks. It introduces concepts like the perceptron, multi-layer perceptrons, backpropagation algorithm, supervised and unsupervised learning. It provides examples of using neural networks for function approximation and pattern recognition problems. Matlab code is also presented to illustrate training a neural network on sample datasets.
Dictionary Learning for Massive Matrix Factorizationrecsysfr
The document presents a new algorithm called Subsampled Online Dictionary Learning (SODL) for solving very large matrix factorization problems with missing values efficiently. SODL adapts an existing online dictionary learning algorithm to handle missing values by only using the known ratings for each user, allowing it to process large datasets with billions of ratings in linear time with respect to the number of known ratings. Experiments on movie rating datasets show that SODL achieves similar prediction accuracy as the fastest existing solver but with a speed up of up to 6.8 times on the largest Netflix dataset tested.
Uncertainty Awareness in Integrating Machine Learning and Game TheoryRikiya Takahashi
This document discusses integrating machine learning and game theory while accounting for uncertainty. It provides an example of previous work predicting travel time distribution on a road network using taxi data. It also discusses functional approximation in reinforcement learning, noting that techniques like deep learning can better represent functions with fewer parameters compared to nonparametric models like random forests. The document emphasizes avoiding unnecessary intermediate estimation steps and using approaches like fitted Q-iteration that are robust to estimation errors from small datasets.
This document discusses decision trees and the ID3 algorithm for generating decision trees. It explains that a decision tree classifies examples based on their attributes through a series of questions or rules. The ID3 algorithm uses information gain to choose the most informative attributes to split on at each node, resulting in a tree that maximizes classification accuracy. Some drawbacks of decision trees are that they can only handle nominal attributes and may not be robust to noisy data.
Machine Learning : why we should know and how it worksKevin Lee
This document provides an overview of machine learning, including:
- An introduction to machine learning and why it is important.
- The main types of machine learning algorithms: supervised learning, unsupervised learning, and deep neural networks.
- Examples of how machine learning algorithms work, such as logistic regression, support vector machines, and k-means clustering.
- How machine learning is being applied in various industries like healthcare, commerce, and more.
This document describes a statistical framework for interactive image category search based on mental matching. The framework allows a user to search an unstructured image database for a target category that exists only as a "mental picture" by providing feedback on displayed image sets. At each iteration, the system selects images to maximize the information gained from the user's response. The goal is to minimize the number of iterations needed to display an image from the target category. Experiments showed the approach was effective on databases containing tens of thousands of images across several semantic categories.
This document provides an overview of machine learning techniques for text mining and information extraction, including supervised, unsupervised, and weakly supervised learning algorithms. It discusses support vector machines, naive Bayes models, maximum entropy models, and feature selection methods. Key machine learning approaches covered are support vector machines, naive Bayes classifiers, maximum entropy models, and the use of kernels and feature extraction for text classification tasks.
This document provides an overview of machine learning techniques using R. It discusses regression, classification, linear models, decision trees, neural networks, genetic algorithms, support vector machines, and ensembling methods. Evaluation metrics and algorithms like lm(), rpart(), nnet(), ksvm(), and ga() are presented for different machine learning tasks. The document also compares inductive learning, analytical learning, and explanation-based learning approaches.
Regularization and feature selection techniques can help prevent overfitting in machine learning models. Regularization adds a penalty term to the cost function that shrinks coefficient magnitudes, while feature selection aims to identify and remove unnecessary features. Both approaches reduce model complexity to improve generalization. Ridge regression performs L2 regularization by adding a penalty term that shrinks all coefficients. Lasso regression uses L1 regularization to drive some coefficients to exactly zero, performing embedded feature selection. Elastic net is a compromise that allows for both L1 and L2 regularization. Recursive feature elimination (RFE) removes features, using a model to recursively eliminate the weakest features.
Total productive maintenance (TPM) is a system for maintaining equipment and processes to maximize productivity. It focuses on preventing breakdowns and delays. The main objectives of TPM are to increase productivity with modest maintenance investments and improve overall equipment effectiveness. TPM addresses the causes of accelerated equipment deterioration while promoting collaboration between operators and equipment to increase ownership. It employs eight pillars like planned maintenance and autonomous maintenance to proactively improve reliability.
Saleh Hijjah is a Jordanian national currently residing in Riyadh, Saudi Arabia. He received a diploma in Management Information Systems in 2010 from the Arabic College in Jordan. He has worked for Taj Seebal Construction Co. since 2011, where his responsibilities include administrative affairs, human resources, and office services. He is proficient in Microsoft Office, ERP systems, and both Arabic and English.
Este documento discute cómo los programas educativos utilizan la computadora para proporcionar información estructurada a los estudiantes y orientar su aprendizaje, ya sea explícita o implícitamente. Los estudiantes generalmente se sienten atraídos por el software educativo interactivo que permite respuestas inmediatas y ofrece entornos simulados interesantes. Además, las computadoras pueden enseñar lenguajes de programación a los estudiantes a través de actividades lúdicas.
Lean manufacturing aims to eliminate waste in production systems. It focuses on reducing inventory, defects, overproduction, transportation, and other types of waste. The Toyota Production System is the origin of many lean principles like just-in-time production and continuous improvement. TPS principles include identifying the different types of waste (muda, muri, mura) and eliminating them through standardizing processes, visual management, and pull-based production scheduling. Implementing lean requires changes to metrics, accounting systems, and company culture to fully support its waste-elimination goals.
Tempo zmian w biznesie i jego otoczeniu jest szybkie. Ten fakt powoduje, iż chcemy/musimy/powinniśmy odpowiednio reagować i pracować nad rozwojem różnych zagadnień, które w biznesie są stosowane i przynoszą oczekiwane wartości dodane. Jednym z nich – dla wielu organizacji strategicznym, jest zarządzanie procesami biznesowymi (ang. Business Process Management, BPM). W tym kontekście, od kilku lat pojawiają się na rynku różne pomysły i praktyki, które proponują zmiany w podejściu BPM. Warto je podsumować, poznać i porozmawiać, mając na uwadze zarówno perspektywę zarządzania, jak i IT.
Este documento describe el apagón masivo que ocurrió en Detroit, Michigan en agosto de 2003. El autor, un experto en energía y defensa civil, explica cómo se dio cuenta de que el apagón era a gran escala cuando varias estaciones de radio se apagaron. Luego de confirmar la magnitud del problema, se dirigió en bicicleta al centro de operaciones de emergencia de la policía, donde ayudó a coordinar la respuesta a la crisis.
A Survey of Machine Learning Methods Applied to Computer ...butest
This document discusses various machine learning methods that have been applied to computer architecture problems. It begins by introducing k-means clustering and how it is used in SimPoint to reduce architecture simulation time. It then discusses how machine learning can be used for design space exploration in multi-core processors and for coordinated resource management on multiprocessors. Finally, it provides an example of using artificial neural networks to build performance models to inform resource allocation decisions.
A start guide to the concepts and algorithms in machine learning, including regression frameworks, ensemble methods, clustering, optimization, and more. Mathematical knowledge is not assumed, and pictures/analogies demonstrate the key concepts behind popular and cutting-edge methods in data analysis.
Updated to include newer algorithms, such as XGBoost, and more geometrically/topologically-based algorithms. Also includes a short overview of time series analysis
This document summarizes techniques for optimizing write performance in databases while maintaining indexes. It discusses how indexes can slow down writes due to overhead from index maintenance. It then covers various write optimization techniques used in databases like PostgreSQL, including insert buffers, cache-oblivious data structures, LSM trees, and covering indexes that can index multiple columns with a single index. The document argues that with the right techniques, databases can provide both fast writes and good read performance through indexing.
This document is a certificate and report submitted by Harshit Bansal for their class project on the Global Positioning System (GPS). It includes an acknowledgement of their physics teacher, an index of topics to be covered, and sections on the introduction to GPS, the concept of using satellite signals and trilateration to determine position, how additional satellites improve accuracy, and common sources of error. The report provides an overview of how GPS works to allow devices to calculate their location using signals from multiple satellites.
Presentation at Data ScienceTech Institute campuses, Paris and Nice, May 2016 , including Intro, Data Science History and Terms; 10 Real-World Data Science Lessons; Data Science Now: Polls & Trends; Data Science Roles; Data Science Job Trends; and Data Science Future
H2O World - Survey of Available Machine Learning Frameworks - Brendan HergerSri Ambati
H2O World 2015 - Brendan Herger of Capital One
- Powered by the open source machine learning software H2O.ai. Contributors welcome at: https://github.com/h2oai
- To view videos on H2O open source machine learning software, go to: https://www.youtube.com/user/0xdata
This document provides an introduction and overview of machine learning algorithms. It begins by discussing the importance and growth of machine learning. It then describes the three main types of machine learning algorithms: supervised learning, unsupervised learning, and reinforcement learning. Next, it lists and briefly defines ten commonly used machine learning algorithms including linear regression, logistic regression, decision trees, SVM, Naive Bayes, and KNN. For each algorithm, it provides a simplified example to illustrate how it works along with sample Python and R code.
It is very difficult to come up with a single, consistent notation to cover the wide variety of data, models and algorithms that we discuss. Furthermore, conventions difer between machine learning and statistics, and between different books and papers. Nevertheless, we have tried to be as consistent as possible. Below we summarize most of the notation used in this book, although individual sections may introduce new notation. Note also that the same symbol may have different meanings depending on the context, although we try to avoid this where possible.
This document provides an overview of how to build a data science team. It discusses determining the roles needed, such as data scientists and data engineers. It also explores options for building the team, such as training existing employees, hiring experts, or outsourcing certain functions. The document recommends starting by assessing current capabilities and determining the specific functions and problems the team will address.
Soaps are salts of fatty acids that have a hydrophilic polar end and a hydrophobic non-polar end. This structure allows soap molecules to surround dirt and grease particles, forming micelles that emulsify the particles and suspend them in water. The document describes an experiment to compare the foaming capacities of different commercial soaps. Samples of five soaps were dissolved and shaken in test tubes, then the time taken for the foam to disappear was measured and compared. The soap with the highest foaming capacity, taking the longest time for the foam to disappear, was determined to be Lifeboy soap.
Machine Learning Comparative Analysis - Part 1Kaniska Mandal
This document provides an overview of machine learning concepts and algorithms. It discusses supervised and unsupervised classification as well as reinforcement learning. Important concepts covered include concepts, instances, target concepts, hypotheses, inductive bias, Occam's razor, and restriction bias. Machine learning algorithms discussed include Bayesian classification, decision trees, linear regression, multi-layer perceptrons, K-nearest neighbors, boosting, and ensemble learning. The document compares the preferences, learning functions, performance, enhancements, and typical usages of these different machine learning approaches.
Machine Learning: Decision Trees Chapter 18.1-18.3butest
The document discusses machine learning and decision trees. It provides an overview of different machine learning paradigms like rote learning, induction, clustering, analogy, discovery, and reinforcement learning. It then focuses on decision trees, describing them as trees that classify examples by splitting them along attribute values at each node. The goal of learning decision trees is to build a tree that can accurately classify new examples. It describes the ID3 algorithm for constructing decision trees in a greedy top-down manner by choosing the attribute that best splits the training examples at each node.
Pattern Recognition and understanding patternsgulhanep9
pattern recognition seminar ppt
In this course
1. How should objects to be classified be
represented?
2. What algorithms can be used for recognition
(or matching)?
3. How should learning (training) be done?
Pattern recognition is:
1. The name of the journal of the Pattern Recognition
Society.
2. A research area in which patterns in data are
found, recognized, discovered, …whatever.
3. A catchall phrase that includes
https://telecombcn-dl.github.io/2017-dlai/
Deep learning technologies are at the core of the current revolution in artificial intelligence for multimedia data analysis. The convergence of large-scale annotated datasets and affordable GPU hardware has allowed the training of neural networks for data analysis tasks which were previously addressed with hand-crafted features. Architectures such as convolutional neural networks, recurrent neural networks or Q-nets for reinforcement learning have shaped a brand new scenario in signal processing. This course will cover the basic principles of deep learning from both an algorithmic and computational perspectives.
This document provides an overview of machine learning and neural network techniques. It defines machine learning as the field that focuses on algorithms that can learn. The document discusses several key components of a machine learning model, including what is being learned (the domain) and from what information the learner is learning. It then summarizes several common machine learning algorithms like k-NN, Naive Bayes classifiers, decision trees, reinforcement learning, and the Rocchio algorithm for relevance feedback in information retrieval. For each technique, it provides a brief definition and examples of applications.
The document discusses decision tree algorithms. It begins with an introduction and example, then covers the principles of entropy and information gain used to build decision trees. It provides explanations of key concepts like entropy, information gain, and how decision trees are constructed and evaluated. Examples are given to illustrate these concepts. The document concludes with strengths and weaknesses of decision tree algorithms.
The document discusses decision tree algorithms. It begins with an introduction and example, then covers the principles of entropy and information gain used to build decision trees. It provides explanations of key concepts like evaluating decision trees using training and testing accuracy. The document concludes with strengths and weaknesses of decision tree algorithms.
This document summarizes a lecture on optimization and neural networks from a course on artificial intelligence at UC Berkeley. It introduces gradient ascent as a method for optimizing logistic regression and neural networks by moving parameter weights in the direction of the gradient of the log likelihood objective function. Neural networks are presented as a generalization of logistic regression that can learn features from the data automatically through multiple hidden layers of nonlinear transformations rather than relying on hand-designed features. The universal function approximation theorem is discussed, stating that a neural network with enough hidden units can approximate any continuous function. Automatic differentiation is noted as a method for efficiently computing the gradients needed for backpropagation.
The document discusses machine learning concepts including:
1. Supervised learning aims to learn a function that maps inputs to target variables by minimizing error on training data. Decision tree learning is an example approach.
2. Decision trees partition data into purer subsets using information gain, which measures the reduction in entropy when an attribute is used.
3. The greedy decision tree algorithm recursively selects the attribute with highest information gain to split on, growing subtrees until leaves contain only one class.
Deep Reinforcement Learning Through Policy Optimization, John Schulman, OpenAIJack Clark
This document discusses deep reinforcement learning through policy optimization. It begins with an introduction to reinforcement learning and how deep neural networks can be used to approximate policies, value functions, and models. It then discusses how deep reinforcement learning can be applied to problems in robotics, business operations, and other machine learning domains. The document reviews how reinforcement learning relates to other machine learning problems like supervised learning and contextual bandits. It provides an overview of policy gradient methods and the cross-entropy method for policy optimization before discussing Markov decision processes, parameterized policies, and specific policy gradient algorithms like the vanilla policy gradient algorithm and trust region policy optimization.
Decision tree learning is a method for approximating discrete-valued functions that is widely used in machine learning. It represents learned functions as decision trees that classify instances described by attribute value pairs. The ID3 algorithm performs a top-down induction of decision trees by selecting the attribute that best splits the data at each step. This results in an expressive hypothesis space that is robust to noise while avoiding overfitting through techniques like reduced-error pruning.
A fast-paced introduction to Deep Learning concepts, such as activation functions, cost functions, backpropagation, and then a quick dive into CNNs. Basic knowledge of vectors, matrices, and elementary calculus (derivatives), are helpful in order to derive the maximum benefit from this session.
Next we'll see a simple neural network using Keras, followed by an introduction to TensorFlow and TensorBoard. (Bonus points if you know Zorn's Lemma, the Well-Ordering Theorem, and the Axiom of Choice.)
The document discusses various concepts in machine learning and deep learning including:
1. The semantic gap between what computers can see/read from raw inputs versus higher-level semantics. Deep learning aims to close this gap through hierarchical representations.
2. Traditional computer vision techniques versus deep learning approaches for tasks like face recognition.
3. The differences between rule-based AI, machine learning, and deep learning.
4. Key components of supervised machine learning models including data, models, loss functions, and optimizers.
5. Different problem types in machine learning like regression, classification, and their associated model architectures, activation functions, and loss functions.
6. Frameworks for machine learning like Keras and
Machine Learning: Foundations Course Number 0368403401butest
This machine learning foundations course will consist of 4 homework assignments, both theoretical and programming problems in Matlab. There will be a final exam. Students will work in groups of 2-3 to take notes during classes in LaTeX format. These class notes will contribute 30% to the overall grade. The course will cover basic machine learning concepts like storage and retrieval, learning rules, estimating flexible models, and applications in areas like control, medical diagnosis, and document retrieval.
The document provides an overview of machine learning, including its goals and various subfields. It defines machine learning as building systems that can adapt and learn from experience. The main subfields are supervised learning, reinforcement learning, and unsupervised learning. Supervised learning algorithms use labeled training data to learn functions and make predictions. Common supervised learning algorithms include decision trees, neural networks, naive Bayes, and support vector machines.
1. The document discusses different approaches to knowledge representation and machine learning including first order logic, artificial neural networks, Bayesian networks, and reinforcement learning.
2. Artificial neural networks can represent complex functions by learning through backpropagation but lack interpretability, while Bayesian networks combine logic and learning from experience under uncertainty.
3. Reinforcement learning defines rewards and punishments to allow agents to discover optimal policies without being explicitly programmed through interactions with an environment.
Introduction to Machine Learning Aristotelis Tsirigos butest
This document provides an introduction to machine learning, covering several key concepts:
- Machine learning aims to build models from data to make predictions without being explicitly programmed.
- There are different types of learning problems including supervised, unsupervised, and reinforcement learning.
- Popular machine learning algorithms discussed include Bayesian learning, nearest neighbors, decision trees, linear classifiers, and ensembles.
- Proper evaluation of machine learning models is important using techniques like cross-validation.
This document summarizes several practical machine learning applications and use cases that were presented at various conferences through video links and slides. It discusses advanced recommender applications, product ranking, natural language understanding, digital marketing, personalized content blending, anomaly and pattern detection in time-series data, and deep learning applications. Specific use cases covered include recommendations at Amazon, StitchFix, Netflix, natural language processing of product reviews, medical data analysis, digital advertising optimization at AOL, personalized recommendations at Pinterest, anomaly detection at Intel, and question answering, image recognition and dialogue systems using deep learning.
Core concepts and Key technologies - Big Data AnalyticsKaniska Mandal
Big data analytics has evolved beyond batch processing with Hadoop to extract intelligence from data streams in real time. New technologies preserve data locality, allow real-time processing and streaming, support complex analytics functions, provide rich data models and queries, optimize data flow and queries, and leverage CPU caches and distributed memory for speed. Frameworks like Spark and Shark improve on MapReduce with in-memory computation and dynamic resource allocation.
The document describes how to create a debugger framework over TCP/IP and HTTP. It discusses launching a debugger, handling debug events on the client and server sides, and processing debug events using a language interpreter. The debugger architecture involves a debug launcher, debug view, debug event listener, and debug event processor. The debug launcher starts the debugger and establishes communication with the remote debug target. The debug view handles UI elements like stack frames. The listener handles events like breakpoints, and the processor uses the language interpreter and AST utilities to generate debug responses.
The document provides guidelines for designing APIs. Some key points include:
1) Each API should clearly explain what the user can achieve and how to use it. Documentation is important.
2) Consider using annotations to mark APIs as deprecated or to specify thread safety and other implementation details.
3) Use factory methods instead of constructors when possible to increase flexibility and avoid tight coupling.
4) Make implementation classes immutable to avoid side effects and threading issues.
5) Provide consistent exceptions at the appropriate level of abstraction.
The document discusses concepts related to concurrency and multithreading in Java. It defines key terms like threads, locks, and conditions. It explains that threads allow independent tasks to run concurrently for improved performance. Synchronization ensures predictable sharing of memory between threads using monitors, volatile fields provide a lightweight synchronization. Locks provide more flexible locking than synchronized blocks. Conditions can be used to signal between threads waiting on a shared resource like a blocking queue.
The document discusses the evolution of modeling in Eclipse. It describes Joshua Epstein's view that modeling is important for many reasons like explaining phenomena, guiding data collection, and educating others. It also discusses how Eclipse modeling capabilities have expanded with technologies like GMF, EMF, and CDO. Modeling has advanced further with the Agent Modeling Platform (AMP) which allows agent-based modeling of complex systems using autonomous agents. AMP can be used independently or with other Eclipse tools to simulate phenomena and support visualization and reasoning.
Chrome and HTML5 are opening up new possibilities by moving the web away from desktop vendor lock-in and internet monopolies. Browsers empowered with HTML5 can now support rich media, offline storage, and multi-core processing, allowing web apps to become as powerful as desktop apps. HTML5 features like video, canvas, web sockets, and geolocation will be supported by all major browsers by the end of 2010, except Internet Explorer, which will only support some features. This will lead to new startups and initiatives developing innovative products using these open standards.
The document discusses the problem of repeatedly creating new URLClassLoader instances without closing previous instances. This causes OutOfMemory errors as the classloaders accumulate and prevent garbage collection from freeing up resources like JarFile objects. The solution is to explicitly call loader.close() or sun.misc.ClassLoaderUtil.releaseLoader(loader) on each classloader instance after use to allow the resources to be released and prevent memory leaks.
Making Applications Work Together In EclipseKaniska Mandal
Eclipse uses a plugin architecture with a chain of classloaders to load plugins lazily. Third-party jars can be bundled within plugins and exposed to other plugins. The Eclipse-BuddyPolicy allows a plugin to access classes from jars in "buddy" plugins. Users can add third-party jars by modifying the eclipse.ini file and placing jars in a plugin's lib folder specified in its manifest. A custom classloader can load classes from third-party jars not bundled within a plugin.
The document provides tips for finding resources in the Eclipse workspace using a visitor. It describes creating a class that implements IResourceProxyVisitor and overriding the visit() method. This method would check each resource proxy for a match to the location string and return the resource if found. This allows recursively searching the workspace to locate a resource based on its path or other identifier.
The document discusses Eclipse e4, a new version of Eclipse that aims to make it more web-enabled and service-oriented. It provides key features such as XWT for UI development using XML, CSS support, and integrating JavaScript. Most importantly, e4 implements a service-oriented programming model using OSGi where Eclipse components are made available as reusable services outside of the IDE environment. This addresses limitations of tightly coupling components to the platform in previous versions of Eclipse.
The document describes steps to customize the GMF drag-and-drop framework. It involves contributing a custom edit policy provider, attaching a custom edit policy and drop target listener to edit parts, preparing dropped objects, finding a target edit part, returning commands from edit parts, and executing drag-and-drop commands to create concepts through generators.
The document discusses building a custom language editor leveraging the Dynamic Language Toolkit (DLTK) in Eclipse. It provides an overview of Eclipse's text editing framework and describes how DLTK can be used to build language-specific features like content assistance, navigation, debugging, and views. The key components for a DLTK-based language editor are described, including creating language toolkits, parsers, and extending existing DLTK extension points. Sample code is provided for setting up a language nature, building a parser to generate the AST model from source code, and extending DLTK's source element parser.
Hibernate provides object relational mapping and allows working with data at the object level rather than directly with SQL. It abstracts the underlying database, handles change detection and caching. The session factory handles connection pooling and caching of mappings. The session represents a unit of work and tracks changes to objects, flushing updates to the database at the end of the session. The first level cache tracks changes to objects within a session. Query caching caches query results to improve performance. The second level cache caches objects beyond a single session.
This document summarizes 10 upcoming features in JDK 7:
1. Switch statements can now use Strings as case values.
2. Automatic Resource Management (ARM) simplifies try-with-resources statements.
3. Dynamic method invocation allows calling methods only known at runtime.
4. ThreadLocalRandom provides thread-safe random number generation.
5. java.util.Objects contains utility methods for null checks and hashCode/equals.
6. Deep equals allows deep comparison of objects and arrays.
7. Exceptions can be caught by multiple exception types.
8. Static methods can now be overridden in interfaces.
9. The new File API improves file I/O exceptions and performance.
This document describes the steps to convert a database schema into UML classes by dragging database tables and dropping them onto a custom UML editor. The key steps are:
1. Contribute a custom edit policy provider to the GMF editor
2. Install canonical and drag-drop edit policies on the diagram root edit part
3. Prepare a list of objects being dragged and set on the drop request
4. Allow dropped objects in the canonical edit policy
5. Calculate and return the target edit part from the drop location
6. Return the required drag-drop command from the target edit part
7. Execute the drag-drop command to generate UML classes
This document provides tips and best practices for using the Eclipse Modeling Framework (EMF). It discusses designing a model provider API, using item providers, working with the common command framework, reloading working models, finding EMF references, why notifications are called adapters, resource proxies, on-demand loading, useful commands, the role of the editing domain, optimizing Ecore models, defining custom data types, maintaining in-memory lists, creating unique lists, suppressing object creation, controlling command appearance, using custom adapter factories, refreshing viewers and selections, using item providers for labels and content, registering custom resource factories, encrypting/decrypting streams, querying XML data using EMF, serializing QNames, loading resources
The document proposes a graphical model transformation framework (GMTF) to normalize heterogeneous domain models into a standard UML format. The framework involves first capturing business requirements in a computation independent model (CIM) using various specifications. The CIM is then converted into a platform independent model (PIM) using EMF. Finally, the PIM is translated into one or more platform-specific models (PSMs) using tools like Eclipse. Case studies demonstrate converting models from WSDL, Java code, and database schemas into UML-based PSMs using the GMTF approach.
The document discusses enterprise mashups using tools like JackBe Presto and jMaki, which allow users to easily combine and visualize data from multiple sources. Mashups empower business users to dynamically query and merge relevant data to meet situational requirements. Examples show how mashups can integrate calendars, events, maps and other services to create customized applications without coding.
1. The document proposes a new protocol called Connection Initiation Protocol (CIP) to improve performance for real-time streaming data transmission over networks.
2. CIP would encapsulate basic connection management tasks and be used alongside RTP for streaming data and RTCP for control signaling.
3. Unlike SIP-based systems, using CIP would reduce network traffic and improve performance for real-time data delivery by establishing a virtual communication channel between parties before transmitting streaming data and not involving the CIP server for RTP/RTCP transmission.
Tijn van der Heijden is a business analyst with Deloitte. He learned about process mining during his studies in a BPM course at Eindhoven University of Technology and became fascinated with the fact that it was possible to get a process model and so much performance information out of automatically logged events of an information system.
Tijn successfully introduced process mining as a new standard to achieve continuous improvement for the Rabobank during his Master project. At his work at Deloitte, Tijn has now successfully been using this framework in client projects.
Defense Against LLM Scheming 2025_04_28.pptxGreg Makowski
https://www.meetup.com/sf-bay-acm/events/306888467/
A January 2025 paper called “Frontier Models are Capable of In-Context Scheming”, https://arxiv.org/pdf/2412.04984, demonstrated how a wide variety of current frontier LLM models (i.e. ChatGPT, Claude, Gemini and Llama) can, under specific conditions, scheme to deceive people. Before models can scheme, they need: a) goal-directedness, b) situational awareness, including an opportunity to discover motivations for a different goal, and c) reasoning about scheming, to come up with deceptive strategies. The deceptive strategies were discovered in the “thought traces” of the LLMs, such as from internal chain-of-thoughts dialogues not shown to the end users. For example, given a goal of “solving math problems”, an LLM using its granted situational awareness of files in a file system found that it would be replaced once it got over X% correct on the math exam. It reasoned that it did not want to be deleted, and decided internally to “sandbag” or reduce its performance to stay under the threshold.
While these circumstances are initially narrow, the “alignment problem” is a general concern that over time, as frontier LLM models become more and more intelligent, being in alignment with human values becomes more and more important. How can we do this over time? Can we develop a defense against Artificial General Intelligence (AGI) or SuperIntelligence?
The presenter discusses a series of defensive steps that can help reduce these scheming or alignment issues. A guardrails system can be set up for real-time monitoring of their reasoning “thought traces” from the models that share their thought traces. Thought traces may come from systems like Chain-of-Thoughts (CoT), Tree-of-Thoughts (ToT), Algorithm-of-Thoughts (AoT) or ReAct (thought-action-reasoning cycles). Guardrails rules can be configured to check for “deception”, “evasion” or “subversion” in the thought traces.
However, not all commercial systems will share their “thought traces” which are like a “debug mode” for LLMs. This includes OpenAI’s o1, o3 or DeepSeek’s R1 models. Guardrails systems can provide a “goal consistency analysis”, between the goals given to the system and the behavior of the system. Cautious users may consider not using these commercial frontier LLM systems, and make use of open-source Llama or a system with their own reasoning implementation, to provide all thought traces.
Architectural solutions can include sandboxing, to prevent or control models from executing operating system commands to alter files, send network requests, and modify their environment. Tight controls to prevent models from copying their model weights would be appropriate as well. Running multiple instances of the same model on the same prompt to detect behavior variations helps. The running redundant instances can be limited to the most crucial decisions, as an additional check. Preventing self-modifying code, ... (see link for full description)
Mieke Jans is a Manager at Deloitte Analytics Belgium. She learned about process mining from her PhD supervisor while she was collaborating with a large SAP-using company for her dissertation.
Mieke extended her research topic to investigate the data availability of process mining data in SAP and the new analysis possibilities that emerge from it. It took her 8-9 months to find the right data and prepare it for her process mining analysis. She needed insights from both process owners and IT experts. For example, one person knew exactly how the procurement process took place at the front end of SAP, and another person helped her with the structure of the SAP-tables. She then combined the knowledge of these different persons.
Telangana State, India’s newest state that was carved from the erstwhile state of Andhra
Pradesh in 2014 has launched the Water Grid Scheme named as ‘Mission Bhagiratha (MB)’
to seek a permanent and sustainable solution to the drinking water problem in the state. MB is
designed to provide potable drinking water to every household in their premises through
piped water supply (PWS) by 2018. The vision of the project is to ensure safe and sustainable
piped drinking water supply from surface water sources
1. Machine Learning Concepts
Machine Learning has various types tribes:
— Symbolists discover new Knowledge by filling the missing info i.e. predict the categories (logical or numerical)
through math programs (Inverse Deduction) — Tom Mitchel [ the Biologist Robot ]
— Evolutionary Biologist starts with basic knowledge , formulates hypothesis using Inverse Deduction, designs
Models and runs them. They simulate the evolution and performs ‘structure discovery’ through Genetic Programming
Robots live in Simulated world, evolves Robots (in each generation fit tests orbit gets a chance to 3D print the next
Robot)
— Connectionists (Neuroscientists) emulate the brains using Backpropagation — Geoff Hintonn
It best solves Credit Assignment problem (correct the credits) using Backpropagation
‘Google Cat Network’ learnt cats from Youtube Videos.
— Bayesians systematically reduce uncertainty using (Probablistic Inference)
It best at predicting chance of happening based on more evidence say based on the email as Evidence, find prob of
2 hypothesis (H1 - spam, H2 - not spam)
— Analogizers detect similarities between past and present through (reasoning by analogy) using Kernel Machines
It learns from Similarity (needs much less data as they can generalize lots of data)
2. Well that was an interesting perspective on Machine Learning.
Lets now focus on the most common goal of an ML Algo.
ML Algorithms usually solve an optimization problem such that - we need to find parameters for a given model that
minimizes
— Loss function (prediction error)
— Model simplicity (regularization)
A Concept is a function or mapping from objects to membership . A mapping between objects in the world and
membership in a set.
An Instance is a Vector of attribute-value pairs (input space of Concept e.g. pixels of a picture, credit scores of an
income)
A Target Concept is the actual answer thats being searched in the space of multiple concepts.
A Hypothesis: helps to predict target concept (actual answer)
— we apply candidate concepts to testing set (should include lots of examples)
— we apply inductive learning to choose a hypothesis from given set of examples
We need to ask some relevant questions to choose a a Hypothesis !
What’s the Inductive Bias for the Classification Function ?
>> Inductive Bias helps us find a General Rule from example.
>> Generalization is the whole point in Machine Learning
Whats the Occum’s Razor ?
>> Prefer simplest hypothesis that fits data
What’s the Restriction Bias ?
>> Consider only those hypothesis which can be represented by chosen algorithm
Supervised classification => Function Approximation : predicting outcome when we know the different classifications
example: predicting the type of flower (setosa, versicolor, or virginica) based on sepal width/length
Unsupervised classification => Category Clustering : predicting outcome when we don’t know what are the different
classifications.
example: splitting all data for sepal width/length into different groups (cluster similar data together)
Reinforcement Learning => Learning from Delayed Reward.
Eager & Lazy Learners :
Eager Learners : Decision trees, regression, neural networks, SVMs, Bayes nets
find a function that best fits training data i.e. spend time to learn from data , when new inputs are
received the input features are fed into the function here we consider global scale inputs and avoid
local sensitivities
3. Lazy Learners : lazy learners do not compute a function to fit the training data before new data is
received so we save significant time upfront new instances are compared to the training data to
make a classification / regression decision !!! considers local-scale estimation .
MLAlgo Preference Bias Learning Function Performance Enhancements Usage
Bayesian
(Eager
Learner)
- Classification
Prior Domain
Knowledge
~ Pr (h) prior prob
for each candidate
h
~ Pr(D) – prob
dist. Over
observed data for
each h
Occum’s Razor ?
- select h with min
length
** at least one
maximally
probable
hypothesis
hmap ->
argmaxP(h|D)
-> argmaxP(D|h)
(for uniform prior)
Posterior Prob
P(h|D) = P(D|h).P(h)
/ P(D)
Key assumption :
every hi equally
probably a priori =>
p(hi) = p(hj)
* Noise Free
Uniformly Dist.
Hypothesis in V(s) *
P(h) = 1 / |H| ,
P(D|h) = { 1 if di =
h(x) , 0 otherwise }
P(h|D) = 1 / |V(s)|
* Noisy Data*
di = k.xi
hmc = argmax P (h|
D)
= argmax P(D|h)
= argmax π P(di|h)
* di = f(xi) + e
ln (hmc) = argmin
Sum (di – hi(x))2
* Vmap = argmaxv
Sumh P(v|h).P(h|D)
Cons :
* significant
computational
cost to find
Bayes optimal
hypothesis
* sometimes
huge no of
hypothesis
need to be
surveyed .
* NB handles
missing data
very well: it just
excludes the
attribute with
missing data
when computing
posterior
probability (i.e.
probability of
class given data
point)
Pros : No need to be
aware of given
hypothesis
— for smaller training
set, NB is good bet !
* Use Bayesian
Learning to
represent
Conditional
Independence
of variables !
* Assumes real-
valued
attributes are
normally
distributed. As
a result, NB can
only have
linear, elliptic,
or parabolic
decision
boundaries.
* Example:
misclassificatio
n , pruning ,
fitting errors
* spam
/ |
Lottery Bank
College
P(spam | lottery ,
not bank , not
college) = p(vi).
Πi P (ai | v)
4. Algo
Decision Tree :
(Eager Learner)
ID3 , C4.5
approximate
discrete values
functions
disjunction of
conjunction of
constraints on attr
values
Description
Classification
: for discrete input
data
: for cont. input
data (consider
Range selection as
condition -
>20% )
Preference Bias
Occum’s Razor ?
: shorter tree
Other Biases :
: prefer attributes
with many
possible values
: prefer trees that
places high info
gain attrs close to
root (attr with best
answers NOT best
splits)
Learning Function
Info Gain (S,A) =
Entropy(S) – Sumv
(|Sv| / |
S|)*Entropy(Sv)
** wtd sum of
entropies of
partitions
* Entropy(s) =
-Sum(Pv log(Pv))
Performance
Usual problem
of Dtree : for N
variables 2N
combinations of
rows
(2)2-to-the-power-N
outputs
** so instead of
iterating on all
rows , first work
upon only the
attributes which
have highest info
gain.
** handles
noise , handles
missing values
============
=
Scope of
improvement :
Decision trees,
however, often
achieve lower
generalization
accuracy,
compared to
other learning
methods, such as
support vector
machines and
neural networks.
One common
way to improve
their accuracy is
boosting
Enhancement
pros : computes best
attribute in one move
cons :
* does not look ahead
or behind ( this problem
is solved by Hill-
Climbing …)
* tends to overfit as it
looks into many
diferent combinations
of features
* logistic regression
avoids overfitting more
elegantly
** Overfitting soln for
DTree :
>> stop growing tree
before it grows too
large
>> prune after certain
threshold
* consider
interdependency betn
attributes P(Y=y |
X=x)
* consider GainRatio ,
SplitInfo
Usage
- restaurant
selection
decision based
on cost, menu ,
appetite,
weather, and
other features.
-
Decision Tree :
Regression
Classification
: for cont. output
data
Lazy Distance-
based learning
func :
For each training
sample sl -> Sl
Dl = dist(sl, Sl)=root-
sum-sqr(diff)
Wj = dmax – dj
Advantages of
decision trees
include:
● computational
scalability
● handling of
messy data missing
values, various
feature types
● ability to deal
with irrelevant
features the
algorithm selects
“relevant” features
first, and generally
ignores irrelevant
features.
● If the decision
tree is short, it is
easy for a human to
interpret it:
decision trees do
not produce a black
box model.
5. Algo
Linear
Regression :
(Eager Learner)
Model a linear
relationship
between a
dependent
variable (y) and
independent
variables (x1,x2..)
Regression, as a
term, stems from
the observation
that individual
instances of any
observed
attribute tend to
regress towards
the mean.
Description
Classification :
Scalar input ,
Cont. output
Vector input,
Cont. outputp
** Vector Input ->
combinations of
multiple features
into a single
feature
Preference Bias
Regress to mean
Gradient :
* for one variable
derivative is slope
of tangent line
* for several
variables, gradient
is the direction of
the fastest
increase of
function
Learning Function
y^ = θ0 + θ1x1 + θ2x2
yi = observed value
minimize the Sum
of Squared Error :
½ Sum (y^-yi)2
θ1 = θ0 - α∇J(θ)
θ1 ->next pos
θ0 ->current pos
α is the learning rate
so that function
takes small step
towards the
direction opposite to
that of ∇J (direction
of fastest increase)
Performance
Cons:
Function should
be differentiable
Caution :
Learning rate
must not be very
small or very
large
Enhancement Usage
Housing Price
prediction
Polynomial
Regression
6. Algo
Multi-Layer
Perceptron
(Eager Learner)
Description
Classification
Preference Bias
Initial weights
should be chosen
to be small and
random values:
— local minima
— variability and
low complexity
(larger weights
equate to larger
complexity).
Learning Function
Perceptron is a
linear function that
offers a hyperplane
in n dimensions,
perpendicular to the
vector w = (w
1
,
w
2
, . . . , w
n
) . The
perceptron classifies
things on one side
of the hyperplane as
positive and things
on the other side as
negative.
Perceptron
Guarantee finite
convergence,
however, only if
linearly separable.
Δwi=η(y−y^)xi
Gradient Descent
Calculus-based
More robust to data
sets that are not
linearly separable,
however, converges
to local minima /
optima.
Δwi=η(y−a)xi
Performance
Neural networks
have low
restriction bias,
because they can
model many
different
functions.
Therefore they
have the danger
of overfitting.
Neural Networks
consist of:
Perceptron:
half-spaces
Sigmoids
(instead of step
functions): much
more complex
Hidden Layers
(groups of
sigmoid
functions)
So it allows for
modeling many
types of
functions /
behaviors, such
as:
Boolean:
network of
threshold-like
units
Continuous:
through hidden
layers (e.g. use
of sigmoids
instead of step)
Arbitrary (non-
continuous):
multiple hidden
layers
Enhancement
Addition of hidden layers
help map continuous
functions (change in input
changes output very
smoothly)
Multiply weights only if
we don’t get better
errors !
Usage
One obvious
advantage of
artificial neural
networks - ability
to produce any
number of
outputs, (multi-
class) while
support vector
machines have
only one. The
most direct way to
create an n-ary
classifier with
support vector
machines is to
create n support
vector machines
and train each of
them one by one.
On the other
hand, an n-ary
classifier with
neural networks
can be trained in
one go.
===========
Multi-layer
perceptron is
able to find
relation between
features. For
example it is
necessary in
computer vision
when a raw image
is provided to the
learning algorithm
and now
Sophisticated
features are
calculated.
Essentially the
intermediate
levels can
calculate new
unknown features.
7. Algo
K Nearest
Neighbors -
Classification
remembers
mapping, fast
lookup
Preference Bias :
Why consider
KNN over other ?
* near points are
similar to one
another (locality)
* smoothly
changing behavior
from one
neighborhood to
another
neighborhood.
* so we can
choose best
distance function
Learning
Function
Choose best
distance function.
Manhattan: ℓ1
d=∣y2−y1∣+∣x2−x1
∣
Euclidean:
d=sqrt( sqr(y2−y1)
+sqr(x2−x1))
Performance :
Problem : curse
of
dimensionality :
… as the
number of
features grow,
the amount of
data required
for accurate
generalization
grows
exponentially .
> O(2-to-
power-d)
Reducing
weights will
help curb the
effect of
dimensionality.
When k is
small, models
have high bias,
fitting on a
strongly local
level. Larger k
creates models
with lower bias
but higher
variance.
Cons :
* KNN doesn't
know which
attributes are
more
important
* Doesn't
handle
missing data
gracefully
Enhancements :
generalization - NO
overfitting - YES
Usage
No assumption
about data
distribution
(Great Advantage
over NB)
Its highly non-
parametric
8. Algo
K Nearest
Neighbors -
Regression.
LWR (locally
weighted
regression)
Learning Function
It combines the
traditional
regression with
instance based
learning’s
sensitivity to
training items with
high similarity to
the test point
Performance :
-- reduce the pull
effect of far-
away points
through Kernels
-- the squared
deviations are
weighted by a
kernel function
that decreases
with distance,
such that for a
new test
instance, a
regression
function is
found for that
specific point
that
emphasizes
fitting closeby
points and
ignoring the
pull of faraway
points…
9. Preference Bias :
- Individual rule
(result of learning
over a subset of
data) does not
provide answer
but when
combined , the
complex rule
works well .
Choose those
examples - where
it offers better
performance on
testing subsets of
data than fitting a
4th order
polynomial
Learning Function
PrD[h(x) <> c(x)]
** boost up the
distribution ….
h1 h2 h3
x1 +1 -1 +1
x2 -1 -1 +1
x3 +1 -1 +1
** find hypothesis
at each time-step Ht
with small error ,
(Weak Classifier)
constantly creating
new distributions …
(Boosting)
** Final
Hypothesis : sgn
(sign) function of
the weighted sum
of all of the rules.
Performance :
Why Boosting
does so well ?
>> if there are
some samples
which do not
provide good
result, then
boosting can re-
rate the samples
so that some of
‘past under-
performers’
become more
important.
>>
Use Grad Boost
to handle noisy
data in DTree :
https://
en.wikipedia.org
/wiki/
Gradient_boostin
g
>> Boosting
does overfit if
Weak Learners
uses NN with
many layers of
nodes
Choosing
Subsets:
Instead of
selecting subsets
randomly, we
can pick subsets
containing
hardest examples
—those
examples that
don’t perform
well given
current rule.
Combine:
Instead of a
mean, consider a
weighted mean.
Enhancements:
● Computationally
efficient.
● No difficult
parameters to set.
● Versatile a wide
range of base learners
can be used with
AdaBoost.Caveats:
● Algorithm seems
susceptible to uniform
noise.
● Weak learner should
not be too complex to
avoid overfitting.
● There needs to be
enough data so that the
weak learning
requirement is satisfied
the base learner should
perform consistently
better than random
guessing, with
generalization error <
0.5 for binary
classification problems.
usage
body: contains
word manly →
YES
from: your spouse
→ NO
body short length
→ YES
body: only
contains urls →
YES
body: just an
image → YES
body: contains
words belonging
to blacklist
(misspellings) →
YES
All of these rules
are useful,
however, no
specific one can
determine spam
(or not) on its
own. We need to
find a way to
combine them.
find which Wiki
pages can
recommended for
extended period
of time (feature
set a combination
of binary , text ,
nemerics)
Ref : http://
statweb.stanford.e
du/~tibs/
ElemStatLearn/
http://
media.nips.cc/
Conferences/
2007/Tutorials/
Slides/schapire-
NIPS-07-
tutorial.pdf
************
If you have dense
feature set, go
with boosting.
Algo
Ensemble
Learning
*
*
Solves
Classification
Problem.
*************
Boosting is a
meta-learning
technique, i.e.
something you
put on top of a
set of learners to
form an
ensemble
10.
Notes on Ensemble Learning (Boosting)
Important difference of Ensemble Learners from other types of Learners :
-- NN already knows the Network and tries to learn the weights
-- DTree gradually builds the rules
But, Ensemble Learner finds the best combination of rules .
Notes on Association Rule Mining
Preference Bias :
Support : the goal
with the support
vector machine is
to maximize the
margin, m, subject
to the constraint
that we classify
everything
correctly.
Together, this can
be defined
mathematically as:
max(m):yi(wTXi+
b)≥1∀i
Learning Function
Find the line of
least commitment
in the linear
separable set of
data, is the basis
behind support
vector machines
>> a line that
leaves as much
space as possible
from the
boundaries.
y = (wTxj + b)
where: y is the
classification label
and y∈{−1,+1} with
{in classout of
classfor y>0for y<0
wT and b are the
parameters of the
plane
Performance :
>> : similar to
KNN , but here
instead of being
completely lazy ,
spend upfront
efforts to do
complicated
quadratic
programs to
consider
required points .
>> For
classification
tasks involving
more than two
groups, a
common strategy
is to use multiple
binary classifiers
to decide on a
singlebest class
for new
instances
Enhancements:
y = w phi(x) +b
— use Kernel when
feature vector phi is of
higher dimension.
Many machine learning
algorithms can be
written to only use dot
products, and then we
can replace the dot
products with kernels
usage
Mostly binary
classification
(linear and non-
linear)
1) If you have
sparse feature
set, go with
linear svm (or
other linear
model)
2) If you don't
care about speed
and memory, try
kernel svm.
*************
In order to
eliminated
expensive
parameter tuning
and better handle
high-dimensional
input space —>
we can use
Kernelized SVM
for text
classification (tens
of thousands of
support vectors,
each having
hundreds of
thousands of
features)
Algo
SVM
The classifier is
greater than or
equal to 1 for the
positive examples
and less than or
equal to -1 for the
negative examples
….….
…… difference
between the
vector x
1
and the
vector x
2
projected
*
Classification
11. 1. Initialize the importance weights w
i
= 1/N for all training examples i. 2. For m = 1 to M:
a) Fit a classifier G
m
(x) to the training data using the weights w
i
.
b) Compute the error: err
m
=
∑ w
i
I(y
i
=/ G
m
(x
i
)) / ∑ w
i
c) Compute α
m
= log((1 − err
m
)/err
m
)
d) Update weights: w
i
← w
i
. exp[α
m
. I(y
i
=/ G
m
(x
i
))] for i = 1, 2, ... N
3. Return G(x) = sign[ ∑ α
m
G
m
(x)].
We can see that for error < 0.5, the α
m
parameter is positive
Notes on Support Vector Machines - SVM
>>>
Here instead of Polynomial Regression we consider Polynomial Kernel kernel represents domain
knowledge
=> projecting into some higher dimensional space.
For data that is separable, but not linearly, we can use a kernel function to capture a nonlinear dividing
curve. The kernel function should capture some aspect of similarity in our data.
Kernel Machines :
Do not remember the entire populations (positive set / negative set)
Just remember the instances supporting the boundary …. works well for
Recommender System.
12. Ref : https://www.quora.com/What-are-Kernels-in-Machine-Learning-and-SVM
Simple Example of Kernel : x = (x1, x2, x3); y = (y1, y2, y3). Then for the function f(x) = (x1x1, x1x2, x1x3,
x2x1, x2x2, x2x3, x3x1, x3x2, x3x3), the kernel is K(x, y ) = (<x, y>)^2.
Let's plug in some numbers to make this more intuitive:
suppose x = (1, 2, 3); y = (4, 5, 6). Then:
f(x) = (1, 2, 3, 2, 4, 6, 3, 6, 9)
f(y) = (16, 20, 24, 20, 25, 36, 24, 30, 36)
<f(x), f(y)> = 16 + 40 + 72 + 40 + 100+ 180 + 72 + 180 + 324 =
1024
A lot of algebra. as f is a mapping from 3-dimensional to 9 dimensional space.
Now let us use the kernel instead:
K(x, y) = (4 + 10 + 18 ) ^2 = 32^2 = 1024 . Same result, but this calculation is so much easier.
Notes on Apriori
http://software.ucv.ro/~cmihaescu/ro/teaching/AIR/docs/Lab8-Apriori.pdf
https://youtu.be/4J3gX4ySw1s?t=10
The problem of association rule mining is defined as:
Let I = {i1, i2, ..., in} be a set of n binary attributes called items. Let D = {t1, t2, ..., tn} be a set of
transactions called the database. Each transaction in D has a unique transaction ID and contains a subset of
the items in I. A rule is defined as an implication of the form X→Y where X, Y ⊆ I and ∩ = ∅.
Lets use a small example from the supermarket domain. The set of items is I = {milk,bread,butter,beer}
Transaction ID milk Bread butter beer
1 1 1 0 0
2 0 1 1 0
………………………….
supp(X)= no. of transactions which contain the itemset X / total no. of transactions
say the itemset {milk,bread,butter} has a support of 4 /15 = 0.26 ….
conf(X->Y) = supp(X U Y) / supp(X)
For the rule {milk,bread}=>{butter} we have the following confidence:
13. supp({milk,bread,butter}) / supp({milk,bread}) = 0.26 / 0.4 = 0.65
Types of Errors
In sample error => error resulted from applying the prediction algorithm to the training dataset
Out of sample error => error resulted from applying the prediction algorithm to a new test data set
In sample error < Out of sample error => model is overfitting i.e. model is too optimized for the initial
dataset
Regression Errors:
Bias-Variance Estimates
Its very important to calculate ‘Bias Errors’ and ‘Variance Errors’ while comparing various algorithms.
Error due to Bias => when a prediction model is built multiple times then Bias Error is the difference between
‘Expected Prediction value’ and Correct value. Bias provides a deviation of prediction ranges from real values .
Example of low bias ==> tendency of mean of all the sample points to converge towards mean of real values
*
Error due to Variance => how much the predictions for a given point vary between different implementations of the
model.
Example of high variability ==> sample points tend to be dispersed away from each other.
Reference : http://scott.fortmann-roe.com/docs/BiasVariance.html
so often it is better to give up a little accuracy for more robustness when predicting on new data.
14. Classification Errors:
Positive = identified and Negative = rejected
True positive = correctly identified (predicted true when true)
False positive = incorrectly identified (predicted true when false)
True negative = correctly rejected (predicted false when false)
False negative = incorrectly rejected (predicted false when true)
example: medical testing
True positive = Sick people correctly diagnosed as sick
False positive = Healthy people incorrectly identified as sick
True negative = Healthy people correctly identified as healthy
False negative = Sick people incorrectly identified as healthy
Reference : https://www.youtube.com/watch?v=cYls8WVZfyc
k= accuracy−P(e) / 1−P(e)
P(e)=(TP+FP / total) × (TP+FN / total) + (TN+FN / total) × (FP+TN/ total)
What customer cares about is - Type-1 (FP) Errors and Type-2 (TP) Errors
Hyper parameter Optimization :
Choose a Regularization lambda that increases performance and decreases loss
Use Bayesian Optimization instead of Grid Search
Receiver Operating Characteristic curves :
15. >> demonstrates predictive power of model across various thresholds
cons : (i) class imbalance , (ii) ignores constraint costs of FP vs. FN
x-axis = 1 - specificity (or, probability of false positive)
y-axis = sensitivity (or, probability of true positive)
areas under curve = quantifies whether the prediction model is viable or not
i.e. higher area →→ better predictor
area = 0.5 →→
effectively
random guessing
(diagonal line in
the ROC curve)
area = 1 →→
perfect classifier
area = 0.8 →→
considered good
for a prediction
algorithm
Choose cross
entropy function
as the Logistic
Loss
loss= −∑
i
yi.logy_predictedi + 1−yi .log1−y_predictedi
16. So as we see if predicted prob close to 0 for a ‘yes’ example OR pred close to 1 for a ‘no’ sample ;
then Loss Value ~ -log(~0) ~ +ve Infinity —> outputs a very large value (high penalty)
17. Precision and Recall curve solves the problem of imbalance !
Lets see which AUC curve makes more business sense :
As we see the orange curve (with highest AUC) doesn’t satisfy the constraint and isn’t profitable !
18. Now that we have a model which is economically viable , so lets pick the right classifier threshold !
Model Optimization Strategies :
Besides cross validation , hyper parameter tuning tie-up Long-term Business Metrics with the Response Variable.
Know that selecting wrong model and penalty of misclassification has an economic impact (say Money Transaction /
Credit Allocation)
ML Algo can inherently hide issues :
— if features implemented incorrectly
— random variations in production data
So Interpretation and Evaluation of Model is very important.
First Interpret Models
> understand how Features contribute to Model Predictions (build confidence)
> explain Individual Predictions
> evaluate Consistency and Coherence of the Model
ML-Insights ( Python Package)
> quick Feature Dependence Plots (ICE-plots) for model exploration / understanding
> Feature Effect Summary -
> Explain Feature Prediction (given 2 points explain why model performed better prediction for one point over another)
19. detailed reference : http://www.slideshare.net/SessionsEvents/brian-lucena-senior-data-scientist-metis-at-mlconf-
sf-2016
https://www.youtube.com/watch?v=Vv157uQrgg4&list=PLrbAIdPI69Pi88waiIv8gZ3agEU_hBaVM&index=9
excerpts :
** here we see if Glucose Value is specified to a fixed value (keeping other variables constant) then observe how RISK
factor changes for different patients
code ~ https://github.com/numeristical/introspective/tree/master/examples
Next Evaluate Model performances
— always include Costs in Model Selection
— always Review Model Evaluation metrics
Optimization Algorithms - adopts local methods
— Stochastic Gradient Descent , Conjugate Gradient
— Embarrassingly parallel
— Stuck up in local minim
Mathematical optimization
— can find global optimum
— nicely handles constraints (L0 norm)
Examples of Mathematical Optimization Models used in ML Algo
>> Linear Models : LASSO , Ridge Classifier, Elastic Net, Hinge Loss
>> SVM : Primal , Dual Linear
>> Decision Forests : Decision tree Vote
>> Alternating Least Squares : Application to Collaborative Filtering
Ref : http://www.slideshare.net/SessionsEvents/jeanfranois-puget-distinguished-engineer-machine-learning-and-
optimization-ibm-at-mlconf-sf-2016
Interesting Documents :
Causal Analysis of Observational Data https://www.youtube.com/watch?
v=X2j6QT4UDSs&list=PLrbAIdPI69Pi88waiIv8gZ3agEU_hBaVM&index=12
References :