
The Amazon Percentage Trick - illdave
http://www.barker.dj/blog/the-amazon-percentage-trick
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zissou
Well, as the saying goes:

>> Facts are stubborn things, but statistics are more pliable.

But to [maybe not your main] point, sales rank and quantity sold are most
definitely HIGHLY correlated (if not only for the simple fact that sales rank
is endogenously determined by quantity sold, and other variables, in Amazon's
algorithms). In fact, the log(sales_rank - 1) for items in most categories on
amazon most likely follows an exponential distribution. In this case, if
you're able to put together an estimate for the distribution's shape
parameter, then in theory you can use it and the sales rank to back-out an
_estimate_ for the actual quantity sold.

FWIW.

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micheljansen
This is a bit of a UX Dark Pattern [1], isn't it? The percentage is not
strictly lying, it just means something else than you'd expect.

[1] <http://darkpatterns.org>

