The survivorship bias in book ratings

The survivorship bias in book ratings

Just finished The Fortunes of Africa: A 5000-Year History of Wealth, Greed, and Endeavor by Martin Meredith, and gave it 4 out of 5 stars on GoodReads. At nearly 700 pages of narrative text The Fortunes of Africa is not a small book, but it’s pretty dense with fact and a “quick read”. The author is good at balancing narrative flow with packing a lot of information into any given page.

But as I rated the book I realized that the vast majority of my ratings are 4 out of 5. I reserve 5’s for really good books. But why so few ratings less than 4? Obviously, this is due to survivorship bias: in general, I’m not going to finish a book that I don’t like, and I won’t rate books that I don’t finish.

Additionally, the longer a book is, the better it probably has to be for me to finish it. If it is a short book (less than 200 pages) I may just push all the way through, but in general anything longer and I won’t read “cover-to-cover.” When I was younger I would sample chapters and such, but for whatever reason as I’ve gotten older I generally adhere to the sequential structure as envisioned by the author.

Of course there are exceptions. Stephen Jay Gould’s The Structure of Evolutionary Theory is very long. In general I did not really enjoy reading it (though it has its moments, in particular when it comes to history of science), but finish it I did. I read The Structure of Evolutionary Theory in full because it was Gould’s magnum opus, and the best place to get a sense of his thought without ploughing through his whole oeuvre. Though I did not think much of Gould’s ideas personally (few people with an evolutionary genetics orientation do), he was objectively an intellectual of some standing and influence, so it is useful to understand his thought. He mattered, for better or worse.

The Structure of Evolutionary Theory was Stephen Jay Gould’s last book (he died two months after it was published). He had become such an enormous public intellectual that he was clearly beyond the power of any editors to control his prose flourishes. It’s a prolix repetitious work (I read Wonderful Life more recently, and it benefited from being more tightly written).

In contrast when I read The Twilight of Atheism Alister McGrath I thought it was a decently well written book, but totally unpersuasive on the merits of the substance. But after ten years I think descriptively McGrath was right in some deep ways. So I’d probably change my rating of this book between then and now.

So categories of books I read all the way through:

  • Books I enjoy. I’ve read The Fall of Rome three times. I’ve only read The Genetical Theory of Natural Selection front to back a few times, but some chapters (especially the earlier ones) I’ve read many times.
  • Books which are important. I’ve read probably two dozen translations of Genesis in my life (it’s a short book when standalone, so not a big achievement). A lot of the religious stuff I read is because religion is so important to people, even if it isn’t important to me. Honestly, the same with a lot of philosophy.
  • Books which challenge my viewpoints in a substantive sense. The Structure of Evolutionary Theory and The Twilight of Atheism fall into these categories. I was a much more doctrinaire libertarian when I read Michael Parenti’s Blackshirts and Reds, which engaged some apologia for Marxist-Leninism.

Razib Khan