[Bob Butler]

tl;dr: Amazon's recommendation system is skewed by free and cheap kindle books and no longer works as well as it used to. Is there a good alternative?

Amazon's recommendation system used to be pretty good. I faithfully rated books I'd read or purchased and often discovered new books and authors based on Amazon's recommendations.

Then I got my first Kindle in 2008 and soon discovered free books on Amazon.

Free books skew Amazon's recommendation system. It's based on the idea that if you buy items A, B & C, your tastes are similar to other people who bought the same. But a lot of people grab any free book they see if they have even the slightest interest in the topic.

So you tend to get lots of recommendations for other books that are or have in the past been free.

You can "improve your recommendations" and check "do not use this for recommendations" for the books that you got for free. But, you pretty much have to do this for any book that was ever free -- even if it's a book you paid for or a book you really liked.

And discounted books like the Kindle Daily Deal can also impact the rating. I bought Alan Dean Foster's Spellsinger series when they were offered for $1.99 each. The first couple of pages of my recommendations are heavily influenced by this -- and a lot of the books aren't really related, they just happened to be part of the same sale.

I've pretty much given up on their recommendations at this point. It's not completely worthless, but it takes more effort than I think it is worth to keep it useful. And part of that means excluding books that I'd really like to be part of the recommendation system simply because they happened to be free or cheap at one point.

I'd love to find an alternative. I know of a few sites that give you a recommendation based on a single book or author, but nothing that takes a large set of ratings, both positive and negative, into account like Amazon does.