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 very good book for beginners like myself! In each chapter, the author goes over the materials covered and then step-by-step tutorials and hands-on exercises! It would be better if the author added one tutorial for one section covered in each chapter! I know the book would be thicker! Anyway, this book is a must-have for any beginner! I really enjoy it! :)