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Tony Dowden
02-01-2011, 07:07 PM
In the last two or three years several people have noted that the top end of the NZ rating system has headed north. (See various other threads - including the current NZ Congress)

Is this a desirable trend? Is it fair or reasonable to label this 'inflation'?

Do some NZCF rules (such as entry to the NZ Ch'p) need to be adjusted?

Please feel free to offer your opinion.

CivicChessMan
03-01-2011, 11:11 PM
The following was printed in the NZ Chess magazine in 2009.

Arpad Elo wrote in his book, The Rating of Chessplayers: “An underrated player truly victimizes his opponents regardless of the outcome of the game. A difference between actual strength and indicated rating can result in each opponent losing points, undeservedly. The loss may not be great at any one time but small losses could accumulate into significant amounts.”

Over the past few years, there has been a gradual decline in the distribution of the rating pool of approximately 10%. At the same time, the number of juniors has increased significantly. In period 3 of 2006, there were 213 juniors, in period 3 of 2009, there are 437 juniors in the active rating pool. Juniors usually start with a low rating because they play in low-rated junior tournaments. Most will improve and some will improve significantly, sometimes even in a single rating period.

To counteract this deflation, intermediate ratings for players with exceptional performances have been introduced. There are now four phases in the rating calculation. Phase 1 calculates ratings for unrated and provisionally rated players while phase 2 calculates ratings for established players. Players with an exceptional performance (bonus point gain) in phase 2, get an intermediate rating that equals the pre-period rating plus the basic rating points change. Phases 3 and 4 are repeats of 1 and 2, this time using the intermediate ratings for a player’s opponents.

Using intermediate ratings significantly reduces the negative impact that underrated players have had on the rating pool. The new calculation has been applied retroactively. The cumulative rating point changes therefore have resulted in the sizable increases in ratings for this period.

CivicChessMan
03-01-2011, 11:22 PM
One must also be aware that the number of tournaments submitted to FIDE for rating is a lot fewer than the number of tournaments rated by NZCF. Furthermore, although NZCF and FIDE use ELO rating systems, they are different in implementation.

Qbert
06-01-2011, 10:09 AM
Some data: Here is a comparison of the top 100 active NZ ratings vs current FIDE. The NZ rating is 39 points higher on average.

Club Standard FIDE inactive difference
DIVE, RUSSELL J WE 2460 2375 85
KER, ANTHONY F WE 2444 2336 108
MARTIN, BENJAMIN M S CA 2427 2375 i 52
NOKES, ROGER I CA 2383 2305 i 78
WASTNEY, SCOTT WE 2375 2300 i 75
j WANG, PU CHEN AC 2372 2459 -87
SMITH, ROBERT W MM 2371 2287 84
STEADMAN, MICHAEL V R AC 2362 2242 120
CROAD, NICHOLAS WE 2346 2290 56
GARBETT, PAUL A NS 2328 2287 41
WATSON, BRUCE R AC 2321 2282 39
LUKEY, STEPHEN G CA 2318 2244 i 74
NOBLE, MARK F UH 2291 2233 58
WANSINK, ROBERT OT 2268 * #N/A #N/A
j SHEN, DANIEL AC 2258 2187 71
SPAIN, GRAEME A GA 2254 2217 i 37
HART, RALPH NS 2250 2199 51
SUTHERLAND, JOHN L OT 2250 2054 i 196
MCLAREN, LEONARD J HP 2244 2207 37
j BAIDER, DANIEL WE 2231 2119 i 112
THORNTON, GINO A NS 2225 2187 38
HAN, DANIEL AC 2222 2196 26
ZHANG, PENG LI 2211 2186 i 25
s THOMAS, BENJAMIN UH 2208 #N/A #N/A
WHEELER, BRUCE AC 2190 2130 60
DOWDEN, R. ANTHONY OT 2174 2120 54
NIJMAN, BRIAN WE 2157 2150 7
MILLIGAN, HELEN NS 2148 2048 w 100
VAN DER HOORN, MARK W WE 2147 2155 i -8
BURNS, CHRIS J WA 2145 2054 91
j KRSTEV, MARIO NS 2139 2094 45
BARLOW, MATTHEW J NS 2137 2140 -3
KRSTEV, ANTONIO NS 2129 2094 35
PINIC, NOEL MM 2121 2058 63
BROWNE, JEREMY A HA 2113 2102 11
MARNER, GAVIN WE 2113 2019 94
DAVIS, JUSTIN M PN 2111 2023 88
MACHDOEM, ANDY CA 2107 2129 i -22
HILL, MARTIN WE 2106 1997 109
j CHEN, ANDREW G HP 2103 2052 i 51
MCDONALD, JOHN A WA 2098 2058 40
POMEROY, ARTHUR J WE 2098 2134 i -36
LE BROCQ, MARK J NS 2094 2121 i -27
j WATSON, JEREMY CA 2092 #N/A #N/A
TURNER, MICHAEL G WE 2088 2039 49
MCNABB, MATTHEW D CA 2087 2069 i 18
s GIBBONS, ROBERT E PT 2086 2022 64
QI, CHAO CA 2084 #N/A #N/A
DUNEAS, JOHN MM 2083 2079 4
MCCRONE, JEFFREY NS 2083 2111 i -28
DORDEVIC, IVAN NS 2080 * 2019 61
WILSON, JESSE WE 2078 2036 i 42
JOHNSON, QUENTIN OT 2072 2128 i -56
j MAROROA, SUE Y HP 2070 2019 w 51
s STUART, PETER W NS 2070 2025 45
s TAYLOR, RICHARD AC 2065 1929 136
STUART, RICHARD AC 2054 #N/A #N/A
LEE, EDWARD WE 2052 #N/A #N/A
j ANSELL, ALAN NP 2050 2001 49
BENNETT, HILTON P HA 2046 1974 72
WOOD, DAVID A CA 2042 #N/A #N/A
BEACH, PAUL K AC 2040 2086 i -46
COTTY, RICHARD AC 2036 * #N/A #N/A
NYBERG, MICHAEL WE 2036 1969 67
VAN GINKEL, JOHN P NE 2035 2003 i 32
PERRY, ROGER L AC 2034 2019 15
SELLEN, IAN WE 2032 1980 i 52
GOODHUE, NATHAN AC 2030 1996 34
FUATAI, FUATAI NS 2027 2015 12
LAMONT, IAIN OT 2024 * #N/A #N/A
MCKERRAS, ROSS CA 2022 2016 i 6
LIM, BENJI HP 2016 2049 -33
VAN DER LEE, BERT MM 2016 * #N/A #N/A
s VETHARANIAM, PRINCE A R WA 2016 #N/A #N/A
JACKSON, L ROSS WE 2013 #N/A #N/A
LATIMER, BRYAN AC 2013 2022 i -9
YEE, STANLEY HP 2013 1996 i 17
TANOI, T EDWARD AC 2012 #N/A #N/A
s FRAEMOHS, PETER CA 1999 1970 29
GUNN, NEIL J NS 1996 2011 -15
j LI, LUKE HP 1992 1990 2
FORSTER, WILLIAM WE 1990 1908 82
REEDY, BRENDAN KP 1989 2025 -36
j GAO, HANS AC 1987 1859 128
EVANS, DAVID J NS 1984 1980 4
j HUANG, ALEX WT 1974 2063 -89
VITAL, HENRY PT 1974 1988 -14
j CHEN, EACHEN AC 1972 1937 w 35
j GAO, JUDY AC 1964 1914 w 50
KING, MATHEW J PN 1964 1959 5
REMANESES, RENATO CA 1962 #N/A #N/A
SPILLER, PAUL S HP 1958 1986 -28
s JANISZ, ANDREW HP 1955 #N/A #N/A
MACDONALD, PAUL AC 1954 2033 -79
CARTER, GERALD S UH 1952 #N/A #N/A
j GUNAWAN, BOY REINHARD WT 1951 * #N/A #N/A
j WU, SHIRLEY AC 1948 1637 wi 311
TAN, EDGARDO C NS 1945 1930 i 15
JOHARI, HALIM CA 1940 #N/A #N/A
Average difference 39.28395062