Figure 4
The histogram titled “Person-Item Threshold Distribution” includes the subtitle “Grouping Set to Interval Length of 0.20, making 125 Groups”. The horizontal axis is labeled “Location (logits)” and ranges from negative 12 to 13 with increments of 1 unit. The upper panel represents “PERSONS”. The left vertical axis is labeled “Frequency” and ranges from 0 to 20 with increments of 5 units. The right vertical axis shows percentages from 0.0 percent to 8.3 percent with increments of about 2.1 percent. A histogram of persons appears concentrated between negative 4 and 4 logits, with the highest bars near negative 2 to negative 1 reaching about 17. A green smoothed curve overlays the histogram, peaking near negative 3 at about 20 and showing another rise near 9 logits around 10. Text under “INFORMATION” shows “48.94” and summary statistics: “Total [240] Mean negative 0.327 SD 1.924”. Dashed horizontal reference lines are marked at 12.23, 24.47, 36.70, and 48.94. The lower panel represents “ITEMS”. The left vertical axis is labeled “Frequency” and ranges from 0 to 25 with increments of 5 units. The right vertical axis shows percentages from 0.0 percent to 5.3 percent with increments of about 1.1 percent. Item thresholds are displayed as downward bars clustered mainly between negative 5 and 5 logits, with denser concentrations near negative 3 to negative 1 and near 0 to 2. Additional smaller clusters appear near negative 10 to negative 8 and near 9 to 11 logits. Three elliptical highlights encircle threshold groupings at the far left, central region, and far right. Blue dashed horizontal reference lines appear at frequency levels 5, 10, 15, 20, and 25. Note: All numerical data values are approximated.Person-item map for the initial MEL scale. Source: Authors’ own work