UBB.Developers Forums General Discussion Chit Chat UBB needs some Maths lessons!

OK, take a look at the picture below.


Now, I have been rated twice here, and my average rating is 4.68. Seeing as you can only rate using whole numbers, it means one rating must've been 5, the other 4. Surely that would make the average 4.5. Not according to UBB.

Except the ratings are not done by adding the scores and dividing by the votes. They're weighted percents.



--mark

Ratings are weighted based on the ranking of the person who has ranked you. You may have received a 4 and a 5, but UBB doesn't use a straight arithmatic average, which would have been 4.5.

In your case, the person who rated you a 5 weights higher than the one who rated you less than 5.

-Tacks

UBB just uses that *new* math

Eh?

Wow...

Is anyone else thinking "unnecessary overhead"?

Just a thought

I find the way they rate members, very hard to understand the code.

I was taking a look in ubb_profile.cgi and I just got lost...

Ok, I guess we need a numerical example here.

Lets say you had two votes. One by Rudy Reg and one by Larry Luser.

Rudy Reg is a respected member who has a 5 rating.

Larry Luser is an annoying newbie poseur and has a 1.

Rudy and Larry both rate you. Rudy respects your contribution to the website and rates you a 5 (congratulations for earning the respect of a respected peer).

Larry is a schmuck and rates you a 1 for the hell of it.

Now, if UBB just used a straight average, (1 + 5 ) / 2 = 3

Now that wouldn't be very fair, would it. Why should a Luser influence your rating like that.

Therefore, UBB uses a Weighted Method. If you want to look at the way UBB handles it, check out ubb_profile.cgi

Yeah, its fairly complex, but the bottom line is UBB will calculate the weighted average for each class of ratees (1's, 2's, 3's, 4's, 5's), then add them together to determine your weighted avg.

Not, sure of the exact calculations, but it is probably something similar to this.

Rudy is a 5 and rates you a 5
Larry is a 1 and rates you a 1

Rudy's 5 weights 5:1 to Larry's 1. So your average is around 4.33.

And yes cal, there is a lot of overhead here.

Personally, I dislike ratings (and no not because I don't rate well), but because I don't have an inferior complex that needs to feed off of my rating

-Tacks

That's a great explanation. Wow, it makes more sense then it did a while ago. No wonder my rating was always in the 2's. I was probably getting rated by members who have a 1 or 2...

As discussed in the past, Admins/Mods don't always like using the rating systems, due to the unpredictable and sometimes vindictive nature of l-users. Especially those who don't always agree with your board policies, or have been troublesome.

If you are feeling a bit underappreciated, just go to your Private Administrator and Moderators Forum and ask for a group hug

-Tacks

tackaberry, that is the BEST description of the ratings I've ever had the pleasure to read. Thank you. Mind if I quote you when others ask? Thanks.

No prob, glad to help

I'm just glad you guys didn't use a geometric mean, that would have been hell to try to explain. Of course it would be even more hell to code it

-Tacks

[ July 31, 2001: Message edited by: tackaberry ]

"UBB needs some Maths lessons!"


I'd say some grammar lessons are in order also!

Umm, that seems fine to me.

Just a thought

I think he is referring to the fact that UBB uses far too many semi-colons!


-Tacks

"Maths" is fine in the UK.

It's one of those quirks they have, like using corporate entity names in the wrong context. It's a collective noun, damn it - it needs to be singular! Infopop HAS, not Infopop HAVE.