DS-200 Question #6: Real Exam Question with Answer & Explanation

There are 20 patients with acute lymphoblastic leukemia (ALL) and 32 patients with acute myeloid leukemia (AML), both variants of a blood cancer. The makeup of the groups as follows: Each individual has an expression value for each of 10000 different genes. The expression value for each gene is a continuous value between -1 and 1. With which type of plot can you encode the most amount of the data visually? Rather than use all 10,000 features to separate AML from ALL, you pick a small subnet of features to separate them optimally. You feature vectors have 10,000 dimensions while you only have 52 data points. You use cross-validation to test your chosen set of features. What three methods will choose the features in an optimal way?