Which scientific advancement fundamentally transformed retail recommendation systems around 2015-2016?

Recommendation systems have revolutionized how consumers discover products, with science driving innovations behind the scenes. These AI-powered tools analyze vast amounts of data to predict consumer preferences with remarkable accuracy. The scientific principles powering these systems continue to evolve rapidly, transforming the retail landscape and blurring the line between consumer psychology and computational analysis. Test your knowledge about the scientific foundations of modern retail recommendation systems!

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Deep learning neural networks with embedding techniques
Bayesian probability models for preference prediction
Quantum computing algorithms for faster processing
Blockchain-based collaborative filtering systems