The Power of a 1-Star Review

I am a little worried.

My larger textbook—Game Theory 101: The Basics and Extensive Form—has been doing quite well. This month, it has averaged a little more than ten sales per day. I know that might not sound a lot, but it projects to more than 3500 sales over the course of a year, or $5600. That is a lot of money for a graduate student living off of a small stipend. It’s also a lot for an academic book, most of which will get about 200 sales over their lifetime.

However, my book received its first review yesterday. It was not so good:

I regret this purchase, even at only $2.99. This is way below “101” level. This is about a 6th grade level…[i]f you are considering this product, you are better off reading the Wikipedia articles on Game Theory – it will be free and much more productive.

Needless to say, he gave me 1 star. Now, whenever someone searches for game theory on Amazon, they will see my book is worth one measly star.

How does that impact a seller? Despite averaging more than ten copies per day this month, I have not sold a single one since that time. Yikes.

The part of the review that I put above—the book is very basic. (There is more to the review that I believe is incorrect, but I excluded it from above to keep this conversation focused.) But that’s the point. I want the book to be simple. Game theory should be simple. There should be no magic or hand waving. The number one complain I receive from students taking game theory is that they have no idea how to solve games despite attending every lecture, section, and office hour they could. That’s why I created my video series, which eventually evolved into the textbook.

But his suggestion to read Wikipedia instead is ridiculous. Go read the Wikipedia page on how to solve for mixed strategy Nash equilibrium. Then try to solve the game in this video. Best of luck to you.

My personal feelings aside, consider an objective metric of the quality of a book: the rate of return. Amazon gives you a seven day window to return a Kindle book that does not meet your expectations. My small textbook has a rating of 5 stars (from a single, trollish review). In the last two months, it has a return rate of 0.69%, meaning a little more than 1 in 150 of these books gets returned. (For perspective, I’ve heard anything less than 5% is good, so I’m well below that mark here.)

The bigger textbook? The one with a 1-star review? Zero returns in the last two months. None. Buyers, it appears, like the larger textbook better. Yet it appears from the reviews that the opposite is true.

Edit: Looking back, I noticed I only calculated this from US sales. There was a single return of the bigger textbook from Amazon UK. So the return rate wasn’t exactly zero for the world, but it was darn close.

I’m curious why Amazon does not show the return rate for each book. Writing a review is time consuming, so you might get one review for every couple thousand books you sell. Consequently, the reviews don’t really tell you what the average person thinks of the book. Returning a book, on the other hand, is not costly, since it puts money back in the customer’s pocket. It is a better metric of a book’s value to its customers.

Anyway, hopefully my sales will return. In the meantime, if you have read Game Theory 101: The Basics and Extensive Form, please write a review. =) Whether you think it is five stars or one, at least the review will better reflect what everyone thinks as a whole.