Average rating?

[Utumno]

I am wondering how is the rating (number of stars) of an application in Ovi Store calculated?

I've got an app ( no. 26449 ) which has 10 user ratings ( including the usual 1-star 'does not install' "rating" ) and if you average them you arrive at 3.9 , and yet the app has 3 stars.
I've got another app with 82 user ratings with average of 3.8, and the app has 4 stars. How is that possible?

[wizard_hu_]

It might be something else than a simple average. More recent ratings probably matter more than older ones.
http://en.wikipedia.org/wiki/Moving_average

[Utumno]

Well, here are the last ratings ( present page ) : 4stars, 4stars, 5stars, 4stars. If you weigh the last ratings more, you arrive at even higher average than the 3.9.

Go to http://store.ovi.com/content/26449/reviews and see for yourself.

[jetrix74]

Has there been any reviews (1 star) that has been removed? (faul language or for some other reason) those could still affect to the average... just a thought...

[Utumno]

Nope, nothing like that. It used to be 4 stars, then out of the blue dropped to 3 stars, with no new user rating.
It really looks like Nokia simply micromanages this.

[Utumno]

Moreover, let's take a look at my competition: http://store.ovi.com/content/21559/reviews

17 user ratings with average of 2.88, last ratings: 1star, 1 star, 1 star, 1star (that's for you 'last ratings matter more' people ) and yet - the app has 4 stars.

[lostdev]

Customer can rate app only with stars, without any comments. In this case this rate will be "hidden", i.e. will not be shown in ratings list, but will be taken into account when calculating average.