One statistic that I would like to see gathered is transition
probabilities on keystroke pairs, and higher-order transition rates
between types of commands. Thus, I am most interested in knowing
whether people tend to type strings of "forward-character" commands
(if they do, that lends credence to the proponents of autorepeating
arrow keys). I am interested in knowing how frequently people in
Twenex Emacs type ^X^S^X^Z -- if very frequently, then either ^U^X^Z
needs more publicity, or a separate "save and exit" command might be
a good idea. Do people tend to type long sequences of cursor motion
commands, or do they intersperse cursor motion with printable-
character insertion? I want to know what pairs of functions tend to
occur together so I can design auxiliary keyboards that minimize hand
movement. And so on. These questions require that people keep more
than just running totals of keystroke frequency; I need ordinal data
also. There have been some attempts to collect such data (notably by
Michael Good at DEC); I'd like to see such data collected for a
variety of different editors, in a variety of environments.
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