Bottom-Line Analytics is a consulting group specializing in marketing effectiveness and brand performance analytics, with over 100 years of combined experience. They innovate traditional marketing mix modeling by employing advanced methods to measure media synergies, copy quality, social media engagement, and long-term advertising effects, emphasizing the interconnectedness of marketing channels. Their unique Social Engagement Index (SEI) quantitatively measures consumer sentiment and its impact on brand sales, offering insights for enhancing marketing strategies and mitigating negative brand conversations.