Table 2.
Distance and width parameters characterizing index of difficulty (ID) conditions.
| ID condition (bits) | Distance (cm) | Width (cm) |
|---|---|---|
| 3 | 8 | 2.0 |
| 4 | 12 | 1.6 |
| 5 | 16 | 1.2 |
| 6 | 20 | 0.8 |
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