Effect of doubles partners wins/losses

[damazing]

This question is to those who have any idea of the NTRP algorithm.

If I mostly partner with one person during the adult season and we do well, but he also plays in another league and loses to lower rated players how does that impact our wins? Does the computer recalculate our wins at the end of the season to lower the ratings for the people we beat?

Follow up question - If I think I have a good win against a top of level player but that player then goes on to lose later in the season to a much lower level player does that invalidate my good win?

[wrxinsc]

Your dynamic rating is calculated after each match that counts towards your ratings. And that result is averaged with as many as three matches back.

Keep in mind that your opponents dynamic rating accounts for what the expected result in your match is.

In dubs, if your your partner has a much lower dynamic rating than you, that would lower the expected delta in games won between you and your opponent. In other words good results with a weak partner can raise you and your partner's dynamic rating for that match played (depending on your opponent's dynamic rating).

Future matches you or he play only count relative toward the expected score of that future match played, and then your dynamic rating is averaged back as many as three past matches. Goes on and on like that depending on how many matches you play.

Year end ratings are what you see (i.e. 3.5, 4.0, etc.) in tennislink (you can't see your dynamic rating) and that calculation is done once per year. The year end rating is basically your dynamic rating rationalized with results at Nationals, Sectionals, etc. via benchmarked players.

[schmke]

If your goal is get improve your rating and/or get moved up, you are in a great spot.

As wrxinsc said, by losing to lower rated players in the other league, your partner is likely causing their rating to go down which lowers the expectations for you as a team when you play. If your wins are a lot better than expected, your rating will go up more than it would if you partner wasn't losing in the other league.

Of course, it isn't winning/losing that matters but the number of games won/lost vs the expected delta. So one can't say for sure that your partner's losses are hurting their rating, although if the opponents really are lower rated it is likely true.

How doubles matches are rated does have an interesting dynamic, especially if two players play together a lot. It is possible that both players ratings become inaccurate over time. For example if players A and B always play together and A is 0.2 better than B, if player B improves his game a lot and they start doing better than expected, both A and B's ratings will go up and the 0.2 delta will be preserved. Player B may now be the better player but the ratings don't reflect this. This of course can go the other way too, with the better player getting worse and pushing the other one down. So if you want your rating to be accurate, make sure you don't play every match with the same partner.

And to your follow up question, what a prior opponent does after you play them doesn't affect your rating. Unless of course you play them again, then their rating at the time of the new match is what would impact you. Or, if they end up being a benchmark player, then your match against them may carry more weight in the year-end ratings calculation.

[OrangePower]

The guys above have already given a good explanation of how it works. To your specific questions:

Originally Posted by damazing

If I mostly partner with one person during the adult season and we do well, but he also plays in another league and loses to lower rated players how does that impact our wins? Does the computer recalculate our wins at the end of the season to lower the ratings for the people we beat?

Wins you have before your partner went downhill (haha) are not impacted.
But for matches after that, if his dynamic rating went down, it will actually benefit your rating. Basically the computer sees him as a weaker player, so if you do well together, it must be because of how awesome you are
And the reverse is true for your opponents; their results against you will seem more poor because now the computer thinks your partner is weak.

Originally Posted by damazing

Follow up question - If I think I have a good win against a top of level player but that player then goes on to lose later in the season to a much lower level player does that invalidate my good win?

No. All that matters is your opponent's rating at the time you played.

[damazing]

Thanks for all the insight on this