This is the first article of the article series Illustrative introductions on dimension reduction. “Curse of dimensionality” means the difficulties of machine learning which arise when the dimension of data is higher. In short if the data have too many features like “weight,” “height,” “width,” “strength,” “temperature”…., that can undermine the performances of machine learning. … Continue reading Spiky cubes, Pac-Man walking, empty M&M’s chocolate: curse of dimensionality