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.
I bought this book for my grandson who is really into magic.. They had some really cute ideas on how to do magic.. Yes, I read some of it before giving him the book.. they were practical ideas and not way out there that one would have to buy this or that..