Table 6 Parameter estimates for the EM-CBM probes and CBM-R passages

From: A comparison of two estimation algorithms for Samejima’s continuous IRT model

  EstCRM package EM2 program
a b α a b α
NI 1.265 (.145) 1.126 (.073) .888 (.059) 1.383 (.079) 1.159 (.044) 0.847 (.031)
QD 1.261 (.162) .707 (.046) .870 (.061) 1.385 (.096) 0.726 (.031) 0.821 (.036)
QA 0.932 (.079) 1.789 (.139) .504 (.042) 0.966 (.051) 1.867 (.210) 0.465 (.021)
P1 2.112 (.125) 1.669 (.042) 1.734 (.050) 2.490 (.106) 1.913 (.041) 1.454 (.029)
P2 1.357 (.051) 1.773 (.038) 1.994 (.047) 1.856 (.060) 1.969 (.036) 1.678 (.028)
P3 4.822 (.772) 1.673 (.034) 1.965 (.047) 5.142 (.645) 1.944 (.034) 1.628 (.026)
  1. Note. The standard errors, reported in parenthesis, were obtained using a nonparametric bootstrap sampling based on 500 resamples with replacement