It has seemed to me lately that I'm getting far fewer reviews on Amazon than I used to, considering the number of units I sell. The thought has been nagging at me for some time, and I'm not alone — others seem to be observing the same thing and speculating about causes.
So — you know me. Time to actually crunch a few numbers and try to see if it's true and, if so, why I think it might be happening.
I started running Amazon AMS ads about 15 months ago, and my units sold have shot up gratifyingly. But not my reviews. My ratings are stable and the reviews I get are much the same as they've always been, but there are just fewer of them than I would expect.
First steps — collect the data
I've been meaning to copy my reviews off the retailer sites, especially Amazon, lest they vanish in one of the periodic Amazon purges. So far I've been lucky and haven't lost any, but that can change. It's useful to have them available, not just for ratings on the retail sites, but also as sources of blurb and other publicity text from real readers.
I checked my retailers and confirmed that, yep, I have almost no reviews except on Amazon, and almost all of those on Amazon USA, of course. That made it easy.
I set up a spreadsheet like the one I use for tracking unit sales to track reviews: month/year, source, rating, product, retailer, headline, review text, etc. Then it was off to the races with pivot tables.
Do I have enough data?
I don't make any big push for reviews, just a modest suggestion in the backmatter of the books. I don't have a ton of reviews, but they do keep coming in (slowly), so I'm going to assume there are enough for some valid conclusions. In any case, I don't have any special marketing that might confuse results.
Next — connect the review data to the units sold data
I put a worksheet up with one pivot table for the reviews-by-month, and another with the units-sold-by-month. Then I ran out the data for a comparison from the date my first book came out, in October, 2012.
A model to compare data
The question I wanted to answer was:
Has the percentage of reviews per units sold been declining lately?