<![CDATA[Persistent misconceptions in kinematics continue to impede physics learning outcomes, yet diagnostic instruments in this domain rarely undergo rigorous psychometric evaluation, particularly within Indonesia's Kurikulum Merdeka (Phase F). This study pursued two integrated objectives: first, to perform an initial Rasch calibration of a ten-item Three-Tier Diagnostic Test (TTDT) on linear kinematics; and second, to construct item-level and person-level misconception profiles for Grade XI Phase F students at a public senior high school in Padang, West Sumatra (N = 183, total sampling). Rasch analysis was conducted using Winsteps (v5.2.4), covering item difficulty, person ability, fit statistics, Wright Map targeting, and Mantel-Haenszel differential item functioning (DIF) by gender. Principal component analysis of Rasch residuals (PCA-R) was additionally employed to examine construct dimensionality. All ten items showed acceptable Infit statistics (0.736–1.161) and excellent item reliability (IR = 0.946); five items returned Outfit MNSQ below 0.70, an overfit pattern generally treated in the Rasch literature as a minor concern relative to misfit, and none exceeded the upper 1.3 threshold. No item showed gender DIF beyond the negligible ETS band, a result confined to this single school pending multi-site replication. The PCA-R first contrast eigenvalue of 1.8 supported approximate unidimensionality, although the two graphical-interpretation items loaded together on that contrast, indicating a modest graphical-literacy subdimension worth monitoring in future revisions. Person reliability (PR = 0.539) was consistent with the instrument's short-form, group-diagnostic purpose, and is not sufficient on its own for individual-level diagnostic decisions. The overall misconception rate reached 33.4%; velocity-time graph interpretation (59.0%) and vertical throw (58.5%) emerged as the highest-priority remediation targets. Person-level profiling revealed that 92.3% of students harbored at least one misconception. The calibrated item hierarchy offers a locally anchored starting point that teachers may draw on when planning differentiated Phase F kinematics instruction; whether it improves learning outcomes in practice has not yet been tested and is left to future intervention research.]]>
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