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RD
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Rating deviation RD , bounded to Showdown’s 25–130 range 95% interval: X ± 1.96 ⋅ SEM 95% interval: R ± 2 ⋅ RD [ 3 ] Reliability rises with more independent items RD falls with more games played in a period [ 2 ] Reliability falls with time since calibration RD rises with time since the player’s last game [ 3 ] This is the article’s original contribution: not the observation that a rating has “uncertainty,” which anyone who has seen a percentage sign after a GXE could guess, but the derivation that Showdown’s published RD update schedule is doing formally, on Glickman’s own stated terms, exactly the job Novick’s 1966 axioms assign to a standard error…
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Equation 21 · Pokémon Formal Measurement
This mathematical expression combines the displayed quantities; its precise role follows from the surrounding article text.
Rating deviation RD , bounded to Showdown’s 25–130 range 95% interval: X ± 1.96 ⋅ SEM 95% interval: R ± 2 ⋅ RD [ 3 ] Reliability rises with more independent items RD falls with more games played in a period [ 2 ] Reliability falls with time since calibration RD rises with time since the player’s last game [ 3 ] This is the article’s original contribution: not the observation that a rating has “uncertainty,” which anyone who has seen a percentage sign after a GXE could guess, but the derivation that Showdown’s published RD update schedule is doing formally, on Glickman’s own stated terms, exactly the job Novick’s 1966 axioms assign to a standard error…
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