From: akm@atlantix.cs.uoregon.edu (Anant Kartik Mithal)
Newsgroups: comp.human-factors
Subject: Re: Summary: Trackball vs. mouse
Keywords: trackball, track ball
Date: 2 Jan 93 07:45:18 GMT
Article-I.D.: cs.1993Jan2.074518.3732
Organization: University of Oregon Computer and Information Sciences Dept.

In article <1993Jan2.050512.9322@Princeton.EDU> bathurst@phoenix.Princeton.EDU (Bruce Bathurst) writes:
>I would like to propose, however, that trackballs and mice
>serve different purposes, 

Can you define what these purposes are? Meaning, I would have thought
that they are both pointing devices, so their purpose is to get the
cursor pointer to a particular location, and perhaps to click when the
cursor is at that locaton. 

>and different people need different pointing devices:
>profession	typing skill	pointing device
>----------	------------    ---------------
>Secretaries	Touch		Neither
>Writers		Handicaped	Trackball
>		Two-fingered	Mouse
>		Touch		Both
>
>Secretaries format as they type, according to the instructions on
>their paper "copy".  For them formatting with control and escape keys
>is best, for they needn't remove their eyes from the paper; and
>pointing devices of any kind are of questionable value.

I think that you need to have some real evidence that secretaries
actually need to keep their hands on the keyboard. I am not saying
that they do not keep their hands on keyboards, I'm saying that there
needs to be some strong scientific evidence, as opposed to anecodetal
evidence that this is true. I'd also suggest that the evidence needs
to be recent because in light of the changes wrought in the workplace
blycomputers, it might be that the kinds of tasks that secretaries do
on computers with pointing devices has drastically changed.

I also don't agree that pointing devices are of use of the secretaries
of the kind you describe. What you experience might be a cause of the
kinds of word processors that they are using. In cases where a command
is one that has a long name (e.g. in Word, selecting a font or
paragraph sytle), it can be quicker to use a mouse or other pointing
device. Also, for example, some of the myraid and more obscure
commands in Emacs that starts with a meta-x sequence. Like meta-x
replace-string. 

>Those who look at the keyboard aren't distracted by having to find a
>mouse, though handicaped typists with limited movement find trackballs
>better or necessary.

I don't necessariy agree. I touch type too, and without taking my eyes
off the screen, can locate my mouse (peripheral vision helps, as well
as muscle memory of where I left it), and I can grab and use it, and
get back to my keyboard. From then on, the problems for a mouse and a
trackball are similar.

In your next article, you suggest a trackball near the space bar. This
is exactly what Apple has on their powerbooks. That is probably the
best design of a trackball I've seen so far. Zenith ships a notebook
with a similar design. At least one other PC clone I've seen has the
trackball on the 'edge' - the vertical side of the notebook that faces
the user, sort of 'round the corner.'

	  /	keys    		  /
	 /   z x c v b n m , . / ^ 	 /
	/	space bar		/
        -------------------------------
        |          ( 0 )               |
        -------------------------------

where the () are the buttons, and the 0 is the trackball. The
disadvantage of this style is that you can't put a wrist rest next to
the machine. The Apple style has a built-in wrist rest.

Two approaches designed with the needs of touch typists are the
HomeRow Keyboard from HomeRow Inc., and the ThinkPad's joystick.

The HR keyboard embedds a joystick under the J key. If you type
normally on the J key, it behaves like a normal key. If you hold it
down, and push to any direction, it switches to being a pointing
device, and the cursor scoots around the screen. The F, D and S keys
are the mouse buttons. Very easy to program a 45 button mouse using
this approach... Also a pretty ingenous way of dealing with the
mode-switch problem.

A couple of touch typists I showed it to loved it. Lots of other
people who liked the mouse did not like it so much. If you want more
info about it, write me, we worked on its performance and Fitts
Law testing, comparing it to a mouse.

The IBM thing (can't remember its name), has a joystick between the
HJUY keys. It sticks out above the plane of the keyboard about 1mm, so
it 'doesn't impede typing.' It is also an isometeric joystick, and
behaves similarly. I'm not sure where the mouse buttons are.

cheers,

kartik
-- 
If you quote my article remember to trim it down to the essentials.
Anant Kartik Mithal, 				akm@cs.uoregon.edu
Network Manager, Ph.D. Student			(503)346-3989
Comp. Science, U of Oregon, Eugene, OR 97403  	(503)346-5373 (fax)
Newsgroups: comp.human-factors