Amazon calculates a product’s star ratings using a machine learned model instead of a raw data average. The machine learned model takes into account factors including: the age of a review, helpfulness votes by customers and whether the reviews are from verified purchases.
As an older person who worries about diminished capacity, I love that I can complete the puzzles. Young people should try it to increase their vocabulary and to challenge themselves. A great feeling of accomplishment comes from manipulating letters to make words