[edash]

Why show the second figure to the user? They don't need to see the calculation you made to determine the sort.

Just sort the objects in the order determined by this formula and only show the ratings given by users in the interface.

[jwr]

This was a system where I was supposed to display a star-rating (1-5 stars, with fractional stars as well) for each item.

The people reporting the problems were the users, and yes, this was bias, as they expected averages. That was exactly my point — while the statistics behind this method are sound, it is not what people expect. Building systems that don't do what people expect is difficult.

[esrauch]

This is mildly amusing because above in this thread the exact opposite comment/response happened; someone said they used it for sorting but showed the mean next to items, and got bug reports that 4.5 was sorted above 5.0. The reply was that he should have just exposed the numbers that they are sorting by as the visible rating in the interface.