Table 3.

IRT Item Parameters for the Grit-S Using the Graded Response Model.

Study 1
Item	a1	b1	b2	b3	b4
GS1	1.448	−1.037	−0.037	1.325	2.956
GS3	1.741	−1.188	−0.376	0.592	1.791
GS5	1.937	−1.578	−0.655	0.284	1.706
GS6	2.315	−1.158	−0.482	0.299	1.438
GS2	0.684	−4.073	−1.360	0.573	2.554
GS4	1.219	−4.459	−2.984	−1.581	−0.253
GS7	1.867	−2.744	−1.318	−0.125	1.032
GS8	1.279	−4.305	−2.590	−0.735	0.632
Study 2
Item	a1	b1	b2	b3	b4
GS1	2.495	−1.817	−0.552	0.279	1.518
GS3	2.583	−1.614	−0.467	0.273	1.394
GS5	3.077	−2.009	−0.829	0.012	1.235
GS6	3.133	−1.550	−0.762	−0.226	0.777
GS2	1.453	−2.049	−0.545	0.227	1.678
GS4	1.515	-	−2.859	−1.491	0.033
GS7	2.886	−2.445	−1.203	−0.422	0.685
GS8	1.910	-	−2.186	−1.017	0.495

Note: a1 = slope parameters; bk=threshold parameter for kth threshold. In Sample 2, threshold b1 for GS4 and GS8 was not estimated because only one participant endorsed the lowest category in each of the items.