Asked about Thinking in arrays
How would you handle missing values?
An answer that works
First find out whether missingness is informative, and if so record it as a feature before imputing. Then drop rows missing something essential, and impute the rest with a median or a model, fitted inside the training fold to avoid leakage.
Reading an answer is not being able to give one. The section that teaches this is Thinking in arrays, 6 hours of NumPy & pandas.
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