its measurement except in special circumstances.
Other researchers might have access to locations where such data could more easily be collected such as buildings with existing video cameras posted in hallways, elevators and stairs with a
centralized set of video display units to view people’s
behaviour. Even without the stair use data, we believe
that the present data is a reasonably good indication
that the enhanced sign was effective in changing
people’s use of the elevators. Moreover, the total
number of people using the elevator in the enhanced
sign condition was lower than any of the other sign
conditions, suggesting that more people in that
condition used the stairs.