Table 3. Percentage of Significant (p < .05) t-Tests from 5,000 Simulated Experiments.
| Scenario | Effect size | Mean RT | RT cost | Proportional cost | z-score cost | Mean error | Error cost |
|---|---|---|---|---|---|---|---|
| Note. Values to the left of the vertical bars are the percentage of pseudo-experiments in which older adults showed significantly slower RTs or larger costs (i.e. worse performance). Values to the right of the vertical bars are the percentage of experiments in which younger adults showed significantly slower RTs or larger costs. Values in bold highlight cases in which simulated older adults typically produced relatively lower costs or lower error rates. If the transformed costs control the Type 1 error rate, then the total proportion of significant effects should be approximately 5% in Scenarios B–D. | |||||||
| A: Domain specific deficit | .2 | 2.8 | 2.1 | 6.8 | .8 | 7.9 | .6 | 10.2 | .2 | 3.3 | 1.4 | 5.2 | .9 |
| .5 | 3.5 | 1.9 | 16.5 | .2 | 20 | .2 | 24.9 | 0 | 11.1 | .1 | 17.2 | .1 | |
| .8 | 9.1 | .3 | 46.3 | 0 | 52 | 0 | 70.3 | 0 | 27.8 | 0 | 46.9 | 0 | |
| 1.1 | 11.5 | .4 | 64 | 0 | 71.6 | 0 | 89.9 | 0 | 38.6 | 0 | 64.2 | 0 | |
| 1.4 | 19.1 | .1 | 81 | 0 | 87 | 0 | 97.2 | 0 | 58 | 0 | 83.2 | 0 | |
| B: General slowing | .2 | 4.6 | 1.3 | 8.3 | .5 | 8.7 | .4 | 7.9 | .5 | 11.2 | .3 | 12.9 | .2 |
| .5 | 6.9 | .7 | 12.8 | .2 | 12 | .2 | 8 | .4 | 23.3 | .1 | 27.5 | .1 | |
| .8 | 22.8 | .1 | 29.8 | 0 | 27.6 | .1 | 10.6 | .4 | 58.6 | 0 | 65.6 | 0 | |
| 1.1 | 54 | 0 | 54.7 | 0 | 47.2 | 0 | 16.2 | .2 | 80.1 | 0 | 86.5 | 0 | |
| 1.4 | 59.8 | 0 | 60.9 | 0 | 52.9 | 0 | 15.5 | .2 | 96.2 | 0 | 98.9 | 0 | |
| C: Strategic slowing | .2 | 5.3 | .8 | 5 | .6 | 4.7 | .8 | 3.4 | 1.6 | .7 | 5.9 | .9 | 6.1 |
| .5 | 16.3 | .2 | 15.8 | .1 | 14.4 | .2 | 7.8 | .6 | .1 | 18.2 | .1 | 13.1 | |
| .8 | 52.3 | 0 | 44.6 | 0 | 40.9 | 0 | 26.1 | 0 | 0 | 41.2 | 0 | 24 | |
| 1.1 | 87.8 | 0 | 74.1 | 0 | 65.1 | 0 | 35.7 | 0 | 0 | 62.1 | 0 | 37 | |
| 1.4 | 95.6 | 0 | 87.5 | 0 | 81.4 | 0 | 61.5 | 0 | 0 | 83.9 | 0 | 60.2 | |
| D: Nondecision time | .2 | 8.5 | .6 | 3.5 | 1.7 | 2.6 | 2.1 | 3.6 | 1.5 | 2.3 | 2.2 | 2.8 | 2.2 |
| .5 | 15.7 | .2 | 1.9 | 2.5 | 1.1 | 4.7 | 2 | 2.8 | 1.4 | 3.3 | 1.3 | 3.6 | |
| .8 | 43.5 | 0 | 3.3 | 1.9 | 1.1 | 4.4 | 3.2 | 2 | 2.6 | 2.1 | 3 | 1.7 | |
| 1.1 | 68.1 | 0 | 2.6 | 1.7 | .6 | 6.7 | 2.9 | 1.8 | 3.2 | 1.7 | 4.2 | 1.5 | |
| 1.4 | 88.3 | 0 | 3.4 | 1.3 | .6 | 7.7 | 2.8 | 2.1 | 2.6 | 1.8 | 3 | 1.9 | |