I have wonderded about amazon's stupidity before however I am still surprised about the uselessness of its automatic recommendations. If I bought book A by author X amazon will recommend books B, C, D, &c. by the same author. - That is the whole algoritm afaict.
Not very surprising the implemention of the algoritm is broken, amazon also recommends paperback edition of book A and German translation of book A. Aargh.
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