Which pioneering recommendation algorithm, developed in the late 1990s, revolutionized online retail by using collaborative filtering to suggest products based on the 'wisdom of crowds'?

The world of retail has been transformed by inventions and discoveries that changed how we shop forever. From recommendation algorithms to store layouts, retail innovation has shaped consumer behavior in profound ways. Test your knowledge of the groundbreaking technologies and techniques that revolutionized the shopping experience!

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Amazon's item-to-item collaborative filtering
Google's PageRank algorithm
Netflix's Cinematch system
Walmart's SKU optimization model