ubuntu-phone team mailing list archive

[Selene Scriven <selene.scriven@xxxxxxxxxxxxx>]

* Niklas Wenzel <nikwen.developer@xxxxxxxxx> wrote:
> Apparently, apps are currently only sorted by their star 
> ratings. ... most top-notch applications are beaten by webapps 
> whose owners give them a single 5 star rating.

There are pretty simple scoring mechanisms which should be able 
to vastly improve the sorting...  The most common one I'm aware 
of is to use average plus certainty to come up with an overall 
score.

The exact algorithm can vary, but the basic idea is to get the 
mean average and standard deviation and then shift the score from 
the mean toward the middle by an amount influenced by standard 
deviation and total number of star ratings.

So, an un-rated app would count as 3 / 5 stars.  As more people 
give it 5-star ratings, its score would rise but never quite 
reach 5/5.  Or, as people give it 1-star ratings its score would 
drop but never quite reach 1/5.  If the standard deviation is 
large, it wouldn't shift as much as if the ratings all cluster 
tightly together.  And if it has a lot of ratings, the score can 
be higher or lower than an app with fewer ratings (but only if 
the ratings mostly agree).

This is basically the same way IMDB calculates movie scores.  I'm 
also using it in my music player to guess at the scores of 
unrated songs, to make its "smart random" mode smarter.

I suspect the app store could do the same.


-- Selene