About Me (in case you care):
Old timer from Fischer, Reshevsky, Spassky, Petrosian, etc. era. Active while in high school and early college, but not much since. Never rated above low 1800s and highly erratic; I would occasionally beat much higher rated players and equally often lose to much lower rated players. Highly entertaining combinatorial style, everybody liked to play me since they were never sure what I was going to do (neither did I!). When facing a stronger player many try to even their chances by steering towards simple positions to be able to see what was going on. My philosophy in those situations was to try to even the chances by complicating the game to the extent that neither I nor the stronger player would be able to see what was going on! Alas, this approach no longer works in the computer age. And, needless to say, my favorite all-time player is Tal.
I also have a computer background and have been following with interest the development in computer chess since the days when computers couldn't always recognize illegal moves and a patzer like me could beat them with ease. Now itís me that canít always recognize illegal moves and any chess program can beat me with ease.
But after about 4 years (a lifetime in computer-related activities) of playing computer-assisted chess, I think I have learned a thing or two about the subject. I have conceitedly defined "AylerKupp's corollary to Murphy's Law" (AKC2ML) as follows:
"If you use your engine to analyze a position to a search depth=N, your opponent's killer move (the move that will refute your entire analysis) will be found at search depth=N+1, regardless of the value you choose for N."
Iím also a food and wine enthusiast. Some of my favorites are German wines (along with French, Italian, US, New Zealand, Australia, Argentina, Spain, ... well, you probably get the idea). One of my early favorites were wines from the Ayler Kupp vineyard in the Saar region, hence my user name. Here is a link to a picture of the village of Ayl with a portion of the Kupp vineyard on the left: http://en.wikipedia.org/wiki/File:A...
You can send me an e-mail whenever you'd like to aylerkupp gmail.com.
And check out a picture of me with my "partner", Rybka (Aylerkupp / Rybka) from the CG.com Masters - Machines Invitational (2011). No, I won't tell you which one is me.
Analysis Tree Spreadsheet (ATSS).
The ATSS is a spreadsheet developed to track the analyses posted by team members in various on-line games (XXXX vs. The World, Team White vs. Team Black, etc.). It is a poor man's database which provides some tools to help organize and find analyses.
I'm in the process of developing a series of tutorials on how to use it and related information. The tutorials are spread all over this forum, so here's a list of the tutorials developed to date and links to them:
Overview: AylerKupp chessforum (kibitz #843)
Minimax algorithm: AylerKupp chessforum (kibitz #861)
Principal Variation: AylerKupp chessforum (kibitz #862)
Finding desired moves: AylerKupp chessforum (kibitz #863)
Average Move Evaluation Calculator (AMEC): AylerKupp chessforum (kibitz #876)
ATSS Analysis Viewer
I added a capability to the Analysis Tree Spreadsheet (ATSS) to display each analysis in PGN-viewer style. You can read a brief summary of its capabilities here AylerKupp chessforum (kibitz #1044) and download a beta version for evaluation.
I have recently become interested in the increase in top player ratings since the mid-1980s and whether this represents a true increase in player strength (and if so, why) or if it is simply a consequence of a larger chess population from which ratings are derived. So I've opened up my forum for discussions on this subject.
I have updated the list that I initially completed in Mar-2013 with the FIDE rating list through 2016 (published in Jan-2017), and you can download the complete data from http://www.mediafire.com/file/zbrlx.... It is quite large (158 MB) and to open it you will need Excel 2007 or later version or a compatible spreadsheet since several of the later tabs contain more than 65,536 rows.
The spreadsheet also contains several charts and summary information. If you are only interested in that and not the actual rating lists, you can download a much smaller (813 KB) spreadsheet containing the charts and summary information from http://www.mediafire.com/file/k9i67.... You can open this file with a pre-Excel 2007 version or a compatible spreadsheet.
FWIW, after looking at the data I think that ratings inflation, which I define to be the unwarranted increase in ratings not necessarily accompanied by a corresponding increase in playing strength, is real, but it is a slow process. I refer to this as my "Bottom Feeder" hypothesis and it goes something like this:
1. Initially (late 1960s and 1970s) the ratings for the strongest players were fairly constant.
2. In the 1980s the number of rated players began to increase exponentially, and they entered the FIDE-rated chess playing population mostly at the lower rating levels. The ratings of the stronger of these players increased as a result of playing weaker players, but their ratings were not sufficiently high to play in tournaments, other than open tournaments, where they would meet middle and high rated players.
3. Eventually they did. The ratings of the middle rated players then increased as a result of beating the lower rated players, and the ratings of the lower rated players then leveled out and even started to decline. You can see this effect in the 'Inflation Charts' tab, "Rating Inflation: Nth Player" chart, for the 1500th to 5000th rated player.
4. Once the middle rated players increased their ratings sufficiently, they began to meet the strongest players. And the cycle repeated itself. The ratings of the middle players began to level out and might now be ready to start a decrease. You can see this effect in the same chart for the 100th to 1000th rated player.
5. The ratings of the strongest players, long stable, began to increase as a result of beating the middle rated players. And, because they are at the top of the food chain, their ratings, at least so far, continue to climb. I think that they will eventually level out but if this hypothesis is true there is no force to drive them down so they will stay relatively constant like the pre-1986 10th rated player and the pre-1981 50th rated player. When this leveling out will take place, if it does, and at what level, I have no idea. But a look at the 2016 ratings data indicates that, indeed, it may have already started.
You can see in the chart that the rating increase, leveling off, and decline first starts with the lowest ranking players, then through the middle ranking players, and finally affects the top ranked players. It's not precise, it's not 100% consistent, but it certainly seems evident. And the process takes decades so it's not easy to see unless you look at all the years and many ranked levels.
Of course, this is just a hypothesis and the chart may look very different 20 years from now. But, at least on the surface, it doesn't sound unreasonable to me.
But looking at the data through 2016 it is even more evident that the era of ratings inflation appears to be over. The previous year's trends have either continued or accelerated; the rating for every ranking category, except for possibly the 10th ranked player (a possible trend is unclear), has either flattened out or has started to decline as evidenced by the trendlines.
Chess Engine Non-Determinism
I've discussed chess engine non-determinism many times. If you run an analysis of a position multiple times, with the same engine, the same computer, and to the same search depth, you will get different results. Not MAY, WILL. Guaranteed. Similar results were reported by others.
I had a chance to run a slightly more rigorous test and described the results starting here: US Championship (2017) (kibitz #633). I had 3 different engines (Houdini 4, Komodo 10, and Stockfish 8 analyze the position in W So vs Onischuk, 2017 after 13...Bxd4, a highly complex tactical position. I made 12 runs with each engine; 3 each with threads=1, 2, 3, and 4 on my 32-bit 4-core computer with 4 MB RAM and MPV=3. The results were consistent with each engine:
(a) With threads=1 (using a single core) the results of all 3 engines were deterministic. Each of the 3 engines on each of the analyses selected the same top 3 moves for each engine, with the same evaluations, and obviously the same move rankings.
(b) With threads =2, 3, and 4 (using 2, 3, and 4 cores) none of the engines showed deterministic behavior. Each of the 3 engines on each of the analyses occasionally selected different analyses for the same engine, with different evaluations, and different move rankings.
I've read that the technical reason for the non-deterministic behavior is the high sensitivity of the alpha-beta algorithms that all the top engines use to move ordering in their search tree, and the variation of this move ordering using multi-threaded operation when each of the threads gets interrupted by higher-priority system processes. I have not had the chance to verify this, but there is no disputing the results.
What's the big deal? Well if the same engine gives different results each time it runs, how can you determine what's the real "best" move? Never mind that different engines or relatively equal strength (as determined by their ratings) give different evaluations and move rankings for their top 3 move and that the evaluations may differ as a function of the search depth.
Since I believe in the need to run analyses of a given position using more than one engine and then aggregating the results to try to reach a more accurate assessment of a position, I typically have run sequential analyses of the same position using 4 threads and a hash table = 1,024 MB. But since I typically run 3 engines, I found it to be more efficient to run analyses using all 3 engines concurrently, each with a single thread and a hash table = 256 MB (to prevent swapping to disk). Yes, running with a single thread runs at 1/2 the speed of running with 4 threads but then running the 3 engines sequentially requires 3X the time and running the 3 engines concurrently requires only 2X the time for a 50% reduction in the time to run all 3 analyses to the same depth, and resolving the non-determinism issues.
So, if you typically run analyses of the same position with 3 engines, consider running them concurrently with threads=1 rather than sequentially with threads=4. You'll get deterministic results in less total time.
Any comments, suggestions, criticisms, etc. are both welcomed and encouraged.