Peirce's 𝑖 and Cohen's 𝜅 for 2×2 Measures of Rater Reliability

Table 2

Descriptive statistics of $i_{\text{ave}}$ and $\kappa$.

	$i_{\text{ave}}$		Cohen’s $\kappa$		Difference
Parameters $(n,i,j,f)$	Mean	SD	Mean	SD	Min	Max
$\tau =.5$
$500,.5,.5,.5$	.50	.03	.50	.03	.00	.01
$100,.5,.5,.5$	.50	.07	.49	.07	.00	.04
$25,.5,.5,.5$	.51	.15	.50	.15	.00	.08
$500,.5,.9,.5$	.55	.03	.50	.03	.02	.07
$100,.5,.9,.5$	.55	.06	.50	.06	.00	.10
$25,.5,.9,.5$	.55	.11	.50	.12	.00	.16
$500,.5,.3,.7$	.48	.03	.44	.03	.01	.06
$100,.5,.3,.7$	.48	.06	.44	.06	.00	.10
$.25,.5,.3,.7$	.48	.13	.43	.13	.00	.17
$500,.5,.1,.9$	.40	.02	.29	.02	.09	.13
$100,.5,.1,.9$	.40	.03	.29	.04	.06	.14
$25,.5,.1,.9$	.41	.07	.29	.08	.03	.17
$500,.9,.5,.5$	.90	.01	.90	.01	.00	.00
$100,.9,.5,.5$	.90	.03	.90	.03	.00	.01
$25,.9,.5,.5$	.91	.06	.90	.07	.00	.04
$500,.9,.3,.7$	.89	.01	.88	.01	.00	.01
$100,.9,.3,.7$	.89	.03	.88	.03	.00	.01
$\tau =.9$
$500,.5,.5,.5$	.41	.04	.40	.04	.00	.01
$100,.5,.5,.5$	.40	.09	.40	.09	.00	.03
$25,.5,.5,.5$	.40	.19	.39	.19	−.07	.17
$500,.5,.3,.7$	.39	.04	.34	.04	.02	.09
$100,.5,.3,.7$	.39	.08	.34	.08	.01	.16