Junior interview questionAsked at Netflix · interview write-up
Walk me through scaled dot-product attention. What are queries, keys and values, and why divide by the square root of d?
Model answer
Score each token's query against every visible key, divide by √d, softmax, and weight the values. The query is what a token looks for, the key what it offers, the value what it hands over. Dot products grow with d, and large scores push softmax onto one token, where gradients get tiny.
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