Fig. 2
From: Exploring student understanding of the engineering design process using distractor analysis
Example distractor analysis plot. This figure shows an example of a distractor analysis plot for a multiple-choice item. The x-axis displays estimates of student achievement. Student achievement estimates are shown in logits, and these estimates were calculated using the Rasch model. Low values indicate lower achievement, and high values indicate higher achievement. The y-axis shows the observed proportion of responses for a given answer choice. The lines in the plot show the proportion of students who selected each of the four answer choices (A, B, C, or D) at each level of achievement. For this example item, the correct response is C (pink line with triangle plotting symbols)