Amazon calculates a product’s star ratings based on a machine learned model instead of a raw data average. The model takes into account factors including the age of a rating, whether the ratings are from verified purchasers, and factors that establish reviewer trustworthiness.
This is a really wonderful concept! I love how the story plays out in both English and German. The story is a wonderful adventure on the river that will engage young readers. If you'd like to teach your child another language, then you should consider this book!