Table 2.

Measurement Precision Results for the Item Selection Methods.

Item selectionmethods	bias		RMSE		Relative efficiency
	Dimension 1	Dimension 2	Dimension 1	Dimension 2	Dimension 1	Dimension 2
Between-item pool
Correlation = .8
R	0.026	0.033	0.430	0.479	0.559	0.557
MDFIM	0.007	0.015	0.240	0.267	1.000	1.000
MPI	0.015	0.019	0.317	0.363	0.759	0.734
MMPI	0.016	0.026	0.335	0.344	0.717	0.776
Correlation = .4
R	0.029	0.036	0.444	0.546	0.580	0.503
MDFIM	0.008	0.021	0.258	0.275	1.000	1.000
MPI	0.022	0.035	0.337	0.410	0.764	0.670
MMPI	0.025	0.027	0.367	0.372	0.702	0.738
Within-item pool
Correlation = .8
R	0.019	0.020	0.432	0.442	0.540	0.553
MDFIM	0.002	0.009	0.233	0.244	1.000	1.000
MPI	0.010	0.024	0.282	0.353	0.826	0.691
MMPI	0.011	0.011	0.308	0.288	0.757	0.847
Correlation = .4
R	0.009	0.033	0.451	0.481	0.570	0.551
MDFIM	0.002	0.014	0.257	0.265	1.000	1.000
MPI	0.017	0.038	0.308	0.401	0.834	0.661
MMPI	−0.001	0.019	0.377	0.344	0.681	0.770

Note. Four item selection methods in this study were (a) the randomized (R) item selection, (b) the MDFIM, (c) the MPI, and (d) the MMPI. RMSE = root mean square error; MDFIM = maximum determinant of the Fisher information matrix; MPI = multidimensional priority index; MMPI = modified multidimensional priority index.