Some small changes, and a word about ratings.

• Made fixes to the serpentine chat window and words list windows, they now should scroll better, and more naturally
• Changed the Journeyman color to a shade of orange
• Now keeping track of the last time you logged in (part of a larger set of changes that will come later)
• Added an email confirmation field when registering, will prevent email typos
• When a newly registered person tries to log in without validating their account, they now have a more informative error message.
• Some administrative tools have been improved.

Sometime soon I will be changing the ratings algorithm in a major way. It will be simpler, more volatile, and there will be a more direct connection between your rating, your score, and the ratings and scores of the others you play with. I won't get into the exact algorithm currently used, it is too convoluted, but I will talk about the new one, and how you can calculate it...

Let us say there are three people playing in a room. After a game, but before recalculating their ratings, they have the following ratings and scores:

Based on their score and rating, and the respective scores and of the others in the room, each player gets an "expected" score. This is the score that they need to get in order to have their ratings stay the same. If their actual score is greater than their expected score, their ratings will go up, otherwise their ratings will go down. Expected Scores are calculated by dividing the sum of scores (40+90+70=200) by the sum of ratings (1100+1600+1300=4000). The resulting quotient, .05, is multiplied by each person's current rating (i.e. 1100 x .05) to get their expected score. Here's a table...

You can see here that both Alex and Jenny did better than expected, but poor Adam did worse. Therefore, we know that both Alex's and Jenny's ratings will go up, but Adam's will go down. But, how much?

Here is where things get a bit tricky. There is no one perfect way of determining how much their ratings change, because it is mostly arbitrary. It is simply a matter of making up some rules for what the maximum amount of change per game will be, and how much over or under the expected score the player has to be in order to get that maximum. In our case, I've decided that the maximum change in points one can get per game is 16 (the current number), and in order to get +/- 16 points per game you either have to get a score that is 75% greater than expected or 75% worse than expected. For example, Jenny's expected score is 65 points. But if she get's 75% greater than that (or 1.75 x 65), which is 114, then her rating will improve by 16 points. However, if she get's 75% worse than expected (or .25 x 65), which is 16, then her rating will decrease by 16 points. Anywhere from 25% of the expected score to 175% the expected score will bring a range of -16 to +16 points. If you fall outside of that range, your rating will be limited to the maximum change (+/- 16). Also, there is a mimimum allowable rating of 100 and a maximum of 9999, so players will never exceed those amounts.

Let's look at how the players' ratings changed:

I hope this will help you all understand how things are going to change. If you have any questions, shoot me an email and I'll do my best to answer. This new algorithm won't come into effect until probably tomorrow morning.