Rochester economics faculty spends a

Rochester economics faculty spends a lot of time thinking about why people don't walk up escalators.

UPDATE: Another worldwide exclusive to the Door. Steve Margolis, noted NCSU economics professor, explains what the Rochester economists apparently couldn't: why people don't walk up escalators. Here is his analysis:

"Walking up escalators is a bit more dangerous than walking up stairs.
Escalators move, making steps less certain. Also, sharp and moving edges
make recovery from a slip less likely and the consequences of a fall more
severe.

"But that's not the reason that we don't walk up escalators. It's related
but it's not the reason. At the end of an escalator's travel, the
escalator's path flattens. At that point, walking up the escalator becomes
more difficult because the height of each step is different from the
previous one. Unless we concentrate while walking up those last few steps,
we lurch uncomfortably, just as we do when we encounter an odd step in a
fixed stair. It's why architects don't fool around with stair heights the
way they fool around with everything else. They love to be innovative,
hate to be sued.

"Now escalators are ordinarily provided in crowded places. Airports and
department stores. Here's where the general equilibrium stuff comes in. If
the people near the top of the escalator have to stop, so does everyone
who is at all close behind them. If I were an escalator walker, I might
stop for, say, the last six feet of the ride. If you were an escalator
walker, and happened to be just behind me, you would have to cease your
walking at about eight feet from the top. And so on. In crowded places,
then, everybody steps on the escalator and politely waits for their turns
to dismount.

"We acquire our escalator habits in crowded circumstances, which teaches us
to stand, not walk. Most of us don't encounter the things often enough to
develop more complicated habits.

"There are some things we see in the world that are consistent with this.
People do tend to walk on those moving walkways that are also found mostly
in airports. All that same marginal stuff that you were using to discuss
escalators applies here, but most people walk. Also, you will see some
escalator walking when the stores and airports are pretty empty. Again,
all the same marginal values, but no termination problem."