From: Daniel Toebbens gmx de> Date: 13 aug 2007 Subject: PanAtlantic vs. Dojo24 [was: Call for data] In my quest to compare PanAtlantic rating with the one in Dojo24 I have now= data of 20 players. That's enough to establish a general trend. I cannot d= o any of the more specific checks I wanted to do, since the sample group is= still to small. I have 7 rating pairs from America (USA + Canada) and 13 f= rom western Europe (half of those from Germany). I have no data at all from= eastern Europe. There might be some bias in the data: American data are al= l for high rated players, European ones mostly from lower rated ones. All d= ata points should be valid to a degree: For Dojo24 I checked that players h= ad both won and lost games. For PanAtlantic, only players who did play in t= he last two years have been included. I could not check this for Dojo24, si= nce it does not give you information on games older three months.=20=20=20= =20=20=20 So, with a grain of salt, the following results: 1) The old, semi-offical equation can still be used:=20 PanAtlantic =3D 870 + 0.7 * Dojo24 2a) A somewhat better description of the current data gives the equation PanAtlantic =3D 1100 + 0.55 * Dojo24 2b) If you prefer an equation that goes through the origin of the two ratin= g scales: PanAtlantic =3D 150 * Dojo24^0.35 3) The scatter is VERY high. There are players with approximately the same= PanAtlantic rating, but Dojo24 rating 1000 points apart. Dito, about 800 = points difference in the PanAtlantic rating at virtually identical Dojo24 r= atings.=20 4) My very preliminary impression: At high ratings Dojo24 might work better= . The PanAtlantic scale levels out due to lack higher-rated opponents to g= ain points from. At low ratings Dojo24 rating breaks down; presumedly only = a small number of weak players are active in the Dojo. The crossover for wh= ich rating scale works better to reflect the true difference in strength, I= would put it around 1000 points in Dojo 24 and at the Kyu/Dan border in th= e PanAtlantic system.=20 For those who are interested, here is the list of data pairs, rounded to fu= ll 10: PanAtl Dojo24 650 220 1330 140 1360 690 1380 50 1420 800 1470 1000 1490 780 1580 900 1650 1300 1780 1060 1820 1360 1850 1320 1930 1290 1970 1420 2000 1750 2030 1260 2070 2030 2080 2350 2140 1460 2280 1760 Thanks to all, who send data. And if you are still not in the list, I'll wo= rk continously to keep it expanded and updated.=20 --=20 Psssst! Schon vom neuen GMX MultiMessenger geh=F6rt? Der kanns mit allen: http://www.gmx.net/de/go/multimessenger --^---------------------------------------------------------------- This email was sent to: = shogi-l shogi net EASY UNSUBSCRIBE click here: http://topica.com/u/?a2i6Ys.= aCxLL3.= c2hvZ2kt Or send an email to: shogi-unsubscribe topica com For Topica's complete suite of email marketing solutions visit: http://www.topica.com/?p=3DTEXFOOTER --^----------------------------------------------------------------