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Data Scientist
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Machine learning
Data Scientist
Machine learning questions
15 questions on Machine learning for data scientists, easiest first.
Easy
5
High accuracy on rare events
easy
High train score, low validation score
easy
Encoding a city column
easy
Scaling features for kNN
easy
Choosing the number of clusters
easy
Medium
6
Predicting a heavily skewed target
medium
Why a forest beats one tree
medium
Lowering the boosting learning rate
medium
Regularisation that zeroes coefficients
medium
PCA on unscaled features
medium
Using a model on rare positives
medium
Hard
4
Coefficients that keep flipping
hard
Oversampling before cross-validation
hard
Target encoding without leakage
hard
From log-odds to probability
hard
