Facebook made over $500 million just by using a 30-year-old psych trick to change how their video algorithm works.
March 20, 2026
Original Paper
Can Psychological Heuristics Enable Long-Term Optimization? Evidence from Short-Form Video Recommendations
SSRN · 6438559
The Takeaway
Rather than using complex AI to predict average engagement, researchers trained the algorithm to identify the single most 'memorable' moment of a video. This simple behavioral heuristic was more effective at driving long-term user retention than standard machine learning models.
From the abstract
Recommender systems optimized for short-term engagement often hurt long-term consumer satisfaction and retention. Yet optimizing long-term outcomes is challenging because such signals are sparse and noisy. We study short-form video platforms, where identifying videos that drive retention is particularly difficult because content is short and often passively consumed, making it hard to attribute long-term outcomes to any individual video interaction. We examine whether psychological heuristics ca