From: A comparison of the polytomous Rasch analysis output of RUMM2030 and R (ltm/eRm/TAM/lordif)
Item Fit Residuala | Person Fit Residuala | Chi-Squareb | PSIc | UNID T-Testd | ||||||||
Mean | SD | Mean | SD | Value (DF) | p | With | without | |||||
RUMM 2030 | PAIN | Initial | −0.8398 | 1.7301 | −0.4845 | 0.9770 | 24.391 (20) | 0.4969 | 0.9218 | 0.9135 | 4.6800% | |
Final | −0.5336 | 1.1746 | −0.4492 | 0.9127 | 18.5992 (20) | 0.5480 | 0.8781 | 0.8644 | 2.3500% | |||
SPECIFIC | Initial | −0.6052 | 2.1366 | −0.4538 | 1.0702 | 54.0898 (30) | 0.0045 | 0.9220 | 0.9033 | 4.7800% | ||
Final | −0.6266 | 1.5595 | −0.4497 | 0.9686 | 50.3341 (20) | 0.0002 | 0.9016 | 0.8699 | 3.6800% | |||
USUAL | Initial | −0.4119 | 1.7207 | −0.4544 | 0.9432 | 23.1212 (20) | 0.2829 | 0.9208 | 0.8304 | 6.1600% | ||
Final | −0.3182 | 1.8380 | −0.4642 | 1.0076 | 32.1662 (20) | 0.0416 | 0.9217 | 0.8888 | 5.0700% | |||
Item Fit Residuala | Person Fit Residuala | Cronbach’s Alphac | Martin-Loefd | |||||||||
Mean | SD | Mean | SD | Value (DF) | p | |||||||
R | PAIN | Initial | 1.63322 | 1.6195 | −0.0447 | 1.89779 | 0.922 | 370.171(599) | 1.0000 | |||
Final | 1.7807 | 1.6219 | 0.0067 | 1.7558 | 0.872 | 239.851(339) | 1.0000 | |||||
SPECIFIC | Initial | 1.6092 | 0.80491 | 0.12174 | 1.37694 | 0.92 | 392.039(899) | 1.0000 | ||||
Final | 1.7810 | 1.0349 | 0.1273 | 1.3960 | 0.8980 | 246.659(399) | 1.0000 | |||||
USUAL | Initial | 2.73459 | 1.43031 | 0.27866 | 1.84451 | 0.921 | 216.992(399) | 1.0000 | ||||
Final | 2.9494 | 1.9276 | 0.2744 | 2.0210 | 0.9200 | ERROR | n/a |