Hi, Adminbrian, I just won what I thought was a nice game (at 30/15).
The rating screen post-game showed my opponent's dropped one point from 1204 to 1203, whereas mine dropped 130 POINTS from 1864 to 1734.
If this is the normal result, no one will play a lower-rated opponent!? Leftcoaster

Are you still provisionally rated?
 
Tknight

Yes, sir, I'm new at the site, so I suppose provisional. I guess it works out (and we're not playing for $$$). Thanks

provisional ratings fluctuate depending on the strength of your opponent.Once you have an established rating you gain points witj every win.
Big picture your rating here means little or nothing so just have fun and play

Correct, during your provisional rating period your rating is mainly being adjusted to the rating level of the site as a whole rather than to any individual opponent. The first 10 games you play are provisionally rated. You can check the status of your provisional ratings by going to the Member Services tab and then "Account Info."

What kind of rating system is used here? You didn't give a real explanation to the question of Leftcoaster. Never heard of a rating system where someone looses point if he wins! If so, the system is poor. ELO, Glicko etc.. don't work that way. So, is there a site / link to the system you use? Any documentation?

 
For a game between 2 non-provisional players, the standard Elo rating system applies.
 
The rating change is different when a provisionally rated player is involved. The provisional formula is quite standard and in widespread use (although often modified in various ways):
 
Prov Rating = {Average Rating of Opponents} + 400(Wins-Losses)/{Number of Games}
 
This basic formula is commonly used with Elo-based systems to handle the first few games since the actual Elo equations cannot be used without an "established" rating figure. Glicko is a whole different animal, and does not use provisional ratings.
 
The loss of points after winning a game may be surprising but it is the natural result of the equation which is intended solely to assign a reasonable figure as quickly as possible without trying to be exact. Fine-tuning of the rating happens after the provisional period has ended.
 
Although many organizations use this exact formula, some do "disguise" it in some way to avoid confusion. One common method is to not display any number at all until after, say, 5 games have been played, which makes the issue much less noticeable (USCF used to do it this way). Another way is to display a fixed value (e.g. 1200) until the entire provisional period is over, and then switch to the calculated value (many online sites do this). Note that these methods do not change the actual calculations, they just keep players from seeing the intermediate results.
 
One thing to keep in mind is that sole purpose of rating adjustments is to increase future predictability. Rating points should not be thought of as "rewards" for winning a game, and losing points is not a punishment. Rating points have no inherent value, and only serve as predictors of relative performance. If we arbitrarily deducted 100 points from everyone's ratings, nothing would actually change. Likewise if we added 100 points. Ratings have to be viewed as a complete system, and individual adjustments must be considered in that context.