Experiment 2 showed that the timing accuracy of different keyboards varied from 1 to about 40 msec. Those PS2 keyboards had poor performance, especially.
The slight difference in response time of 1 msec would not be perceivable, and is likely due to measurement variability.
响应时间的差异只有 1 msec,可以无需考虑,而且可能是由于测量的误差引起的。
3
The work will be performed by ManTech Systems Engineering Corporation (MSEC), a wholly owned subsidiary of ManTech, headquartered in Lexington Park, Md.