♡ 20 ( +1 | -1 ) this is the issue. 40 years ago when I played on my college chess team I had a USCF rating of about 1500. 40 years later my GK rating is about 1700. Am I getting better or worst?
♡ 74 ( +1 | -1 ) ...If I were in your shoes, I would take the optimist's route and believe that you are better than you were 40 years ago. That said, I think the GK rating generally inflates the "true" value of your rating ("true" because who's to say that USCF is all that accurate, either?).
There's also the possibility that your skill level remained about level. Did you read any chess books over the past few years? Have you gone over many of your games to find where you make mistakes? Do you find yourself noticing more or less inspired moves when you're playing?
Either way, if you've played for the past 40 years, I'd find it hard to believe you're getting worse.
♡ 58 ( +1 | -1 ) OTB is different. On GK, you have more time to make the move. Your quality of game should improve because of less time pressure. A 1500 game played on GK is going to look more accurate on average than one played OTB at the presumed same class level. Some people cannot necessarily translate their skills at GK to OTB, nor OTB skills to GK performance. These are different skills sets that are difficult to transfer. Yet, just playing more accurate more often should eventually improve OTB play. It just takes time.
♡ 27 ( +1 | -1 ) Chessnovice:If you doubt the accuracy of GK ratings vs. other CORRESPONDENCE ratings, check out the performance of Cairo's team of GK players (Peace: The Power That Preserves) in the ICCF team championships (see links on his player page) or Rodog's ICCF performances (see links on his player page).
♡ 22 ( +1 | -1 ) ...I don't doubt the relative strength of their ratings. I'm certain that Cairo's team is very talented. I just know from my personal vantage point... I don't really believe I play at an 1800 level.
♡ 81 ( +1 | -1 ) Still Thinking "Absolute"Even though you acknowledge in the first clause that chess ratings are relative to the population of the rating group, your last clause shows that you are still thinking of "1800 level" as some absolute. All it actually reflects is your position in a particular population of players, because that is all that Arpad Elo's system is designed to show. Thus, one cannot even compare Fischer's 2800 rating with Kasparov's or Topolov's because they lived in different times and even though they played in the same rating system, the population changed as players aged, died, and were replaced. If you hold a GK 1800 rating across some significant number of games and did not get it via timeouts, etc., then you are playing at an 1800 level IN THAT POPULATION.
♡ 5 ( +1 | -1 ) ...Good point, that is an inconsistency on my part.
♡ 89 ( +1 | -1 ) And of course you can add or subtract any number you please from ratings. One would approximately expect a 1800 on gameknot is to score about the same against a 2200 on gameknot as a 2000 FIDE versus a 2400 FIDE (i.e. the rating difference means the same thing), at least if their past performance is indicative of their chess strength.
However even if the two ratings measured the same kind of skill (which they probably don't exactly), then it would still not be clear which points on the scales correspond to each other. Of course if the rating were comparable, then one would be able to look at players that have both ratings and possibly be able to figure out a reasonable conversion. However as said before we probably have to expect that CC and OTB ratings simply measure two related, but not identical kinds of past performance.