Table 1.
Descriptive statistics by age on performance measures.
| 6–7 years | 8–9 years | 10–11 years | 12–14 years | Adults | |
|---|---|---|---|---|---|
| Number of perceived identitiesa(max = 40) | |||||
| Mean (SD) | 18.81 (9.34) | 15.68 (10.42) | 17.55 (8.51) | 14.38 (5.58) | 10.60 (9.28) |
| Median | 17.5 | 12.5 | 16 | 14 | 5 |
| Range | 7–40 | 2–38 | 3–32 | 7–26 | 2–28 |
| Misidentification errorsb | |||||
| Mean (SD) | 3.63 (2.78) | 2.21 (2.28) | 0.95 (1.19) | 1.54 (1.39) | 0.20 (0.41) |
| Median | 3.5 | 2 | 0.5 | 1 | 0 |
| Range | 0–9 | 0–8 | 0–4 | 0–4 | 0–1 |
| Matrix scorec | |||||
| Mean (SD) | 13.76 (22.66) | 61.08 (136.81) | 63.92 (75.09) | 43.17 (48.74) | 433.20 (296.76) |
| Median | 3.08 | 10.48 | 29.50 | 18.25 | 518.00 |
| Range | 0–84 | 1.97–562 | 5.17–252 | 4.33–142 | 46–760 |
a
Number of perceived identities is the number of image piles (each representing a different perceived identity) that participants sorted the 40 photographs into within the 10-min time limit.
b
Misidentification errors is the number of times participants’ image piles featured more than one real identity (i.e., both Dom and Rob).
c
Matrix score is the number of times two images of the same real identity were placed together (as recorded in the top-left and bottom-right matrix quadrants) divided by the number of times two images of differing identities were placed together (as recorded in the top-right matrix quadrant). Higher scores indicate better performance.