Trader Rating:
Your trader rating is calculated from the ratings that others leave for you. The value ranges from -50 (worst) to +50 (best). Everyone receives a +0 rating if they haven't been rated yet. The value isn't a simple average however. When you leave a rating a weighting for that rating is calculated based on the amount of time you have been a member. When you are a new member you will have a very small weighting power. When you've been a member for as long as I have you will have almost the maximum weighting power. The reason for this is to combat people signing up fake accounts and rating themselves highly. In theory genuine ratings will outweigh the newbies rating.
How is the weighting calculated? Well, up until you've been a member for about 154 weeks your weighting increases pretty much linearly (though it isn't 1 weighting point per week). Once you get to 155 weeks as a member your weighting power switches over to a log scale. This essentially caps your weighting power while still allowing it to increase slightly though not as fast as before. This prevents one person from gaining a weighting power thats excessively high. We store all the raw data necessary to recalculate peoples weighting in case we decide to make drastic changes to the weighting system.
From there to calculate the rating is fairly simple:
First we add up everyones weighting power.
Then we calculate each submitted weighted rating:
(weight*rating)/total weight
And then simply add all of those together.
I should also mention that theres some rating damping if someone receives very high ratings as their first few reviews. This goes away once you've had a few more ratings submitted.
Risk-o-meter:
Basically the risk meter attempts to establish how potentially risky it is to deal with this person. The key thing to remember when looking at this value is that it is just computer calculated. The computer has no way of judging the character of this person so we have to give it numbers to look at instead. The algorithm I've written takes a bunch of data from the forum and attempts to profile a person based on roughly the profile most scammers appear to take. Now this does not mean that a low value automatically means someones a scammer. It does mean that, to the computer, this account shows a profile that is possibly like a scammers account. Its not fool proof, at all. You should ALWAYS ALWAYS use YOUR judgement!! I cannot stress this enough. As a persons account profile looks less and less like a potential scammer account the system improves your Risk-o-meter rating.
Things that affect your Risk-o-meter rating:
The amount of time you've been a member. This is pretty much the biggest non-rating factors that will affect your Risk-o-meter rating. If you've only been a member for a short period of time the system penalises you. As the time you've been a member increases the penalty becomes less and even positive when you've been a VERY long term member. The only way to affect this is time, so don't stress about it.
Your post count Yes you receive a small penalty if you have a low post count and a slight boost if you have a very high count. Hopefully this doesn't encourage spamming or I will have to warn you (see below).
Your Warning level You receive a penalty of 10 for every warning you receive meaning that if you've had the maximum 10 warnings you get a risk rating of 100 (the worst). So, don't spam or be a dweeb.
Your user group This only applies if you're an Admin, Mod, Bad Trader, Suspended or Banned. Admins and Mods get a risk rating of 0 because they're so awesome. Conversely Bad Traders, Suspended or Banned accounts receive a risk rating of 100 because obviously they've done something very bad.
Your Rating This is (currently) by far the easiest way to improve your Risk-o-meter rating. Get good reviews from your trades and the Risk-o-meter will give you a good risk rating. If I find people consistently abusing the system I'll reduce the power of this to improve your rating.
Future additions
Bump penalty bot: This will be a robot that scans the for sale areas for breaches the bumping rules. It won't remove your post but your RATING (not risk rating) will be hit with a penalty. I haven't decided how much the penalty will be yet but it will be fairly hefty so something to avoid at all costs.
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