Capability Estimation of Student's Higher Order Thinking in Mathematics by Using Polytomous

One of the alternative approaches in the scoring of items that can be used is the Latent Trait Theory Approach for polytomous scoring with a Generalized Partial Credit Model (GPCM). This study aimed at estimating the test taker’s capability to think critically (higher order thinking) in maths in the form of essay questions with items scoring in GPCM by considering the level of difficulty in each of the steps that must be taken to obtain the correct answer. The instrument used in this study was essay question developed. The data analysis used in this study was SPSS version number 22 and Parscale from Ssi. SPSS version number 22 was used to detect the sufficiency requirements of the number of samples used and prerequisite analysis of scoring using the GPCM method. Parscale was used to estimate the capability of respondents. The estimation of capability was presented in Phase 3 on a scale (-4, +4) in which, then, it can be transformed with a linear transformation to the equation x = 12,5θ + 50, x is the estimation of capability in the range of [0,100]. The result of capability estimation was in the range of [0,100] so that it was obtained the minimum capability estimation 49.36 and maximum 100.