Very Slow Search and Reach: Failure to Maximize Expected Gain in an Eye-Hand Coordination Task
Figure 5
Search-Reach: Human observers' performance compared to optimal.
A. Efficiency. Efficiency was defined as the average gain of successful trials divided by the maximal expected gain. Most observers were far from optimal. The median efficiency across observers was 78%. B. Movement time after the target was found. Black dot denotes the expected movement time after the target was found if the observer used the optimal visual search and hand movement strategies. All the observers' mean post-found movement time were larger than the minimum expected movement time. For 6 of the 8 observers, the difference was significant. In both A and B, each bar is for one observer. Error bar denotes the 95% confidence interval.