实验如下:
矩阵dt_x,胡乱构造的:
[,1] [,2] [,3] [,4] [,5] [,6] [,7]
[1,] 1 0 1 1 NA 0 1
[2,] NA 1 1 0 1 0 NA
[3,] 0 0 1 1 1 1 0
[4,] 1 NA 0 1 NA 0 1
[5,] 1 0 1 1 0 1 1
[6,] NA 1 1 NA 1 1 NA
[7,] 0 0 1 0 0 1 0
[8,] 1 NA 0 1 NA 0 1
>fit_x <- LPCM(dt_x)
>summary(fit_x)
Results of LPCM estimation:
Call: LPCM(X = dt_x)
Conditional log-likelihood: -16.82988
Number of iterations: 9
Number of parameters: 6
Basic Parameters eta with 0.95 CI:
Estimate Std. Error lower CI upper CI
eta 1 -1.549 0.980 -3.470 0.371
eta 2 0.624 0.760 -0.865 2.113
eta 3 0.624 0.760 -0.865 2.113
eta 4 -0.232 0.925 -2.045 1.580
eta 5 -0.453 0.687 -1.799 0.893
eta 6 0.494 0.792 -1.058 2.046
Item Easiness Parameters (beta) with 0.95 CI:
Estimate Std. Error lower CI upper CI
beta I1.c1 0.494 0.792 -1.058 2.045
beta I2.c1 -1.549 0.980 -3.470 0.371
beta I3.c1 0.624 0.760 -0.865 2.113
beta I4.c1 0.624 0.760 -0.865 2.113
beta I5.c1 -0.232 0.925 -2.045 1.580
beta I6.c1 -0.453 0.687 -1.799 0.893
beta I7.c1 0.494 0.792 -1.058 2.046
>plotINFO(fit_x)
问题:
利用eRm的LPCM方法计算出来的结果如何理解?
1.Estimate是项目难度吗?
2.eRm里面有什么方法可以评价被试水平呢?