Civil Engineering Reference
In-Depth Information
FIGURE 5.1
Interface design of two
microwave ovens. Design A combines
simplicity and functionality. Design B
leads to confusion and many user
errors.
It puzzles me that these microwave designs have become so popular. However, consider
that the extra controls cost very little to manufacture. To the customer it looks like a
better buy—more for the same investment. But the investment in time due to difficulty of
use is completely ignored. The effect of too much information is easily explained by
Hick's law.
5.3
HUMAN REACTION TIME AND HICK'S LAW
A common performance measure in HFE is human reaction time (RT). The reaction time
varies depending upon what people are reacting to. The most common RT scenario in
real life is probably the start of a running competition: ready, steady, go. In HFE reaction
time is used to measure how complex decisions are. Complex decisions take a long time
and easy decisions take a short time. RT is used to reformulate or redesign decisions so
that they become easier, quicker, and more reliable.
