Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uflorida!gatech!rutgers!orstcs!mist!ruffwork
From: ruffwork@mist.cs.orst.edu (Ritchey Ruff)
Newsgroups: comp.cog-eng
Subject: Re: consistency
Keywords: consistency, desktop metaphor, interfaces, computing environments
Message-ID: <8799@orstcs.CS.ORST.EDU>
Date: 11 Feb 89 00:06:35 GMT
References: <714@cogsci.ucsd.EDU> <1465@thumper.bellcore.com> <83@sundown.ACA.MCC.COM>
Sender: usenet@orstcs.CS.ORST.EDU
Reply-To: ruffwork@cs.orst.edu (Ritchey Ruff)
Organization: Oregon State University - CS - Corvallis, Oregon
Lines: 34

I think if you separate the goal's from the actions (or "acts") in the
interface you might get a bit closer to that elusive "consistency"
definition.  That is (using the mac as an example), clicking
selects something, dragging moves something, etc. instead of
"file commands go in a menu".  With the mac, if the consistency at
this "act" level is violated it is *very* confusing (ever use a mac
program where a double-click does not select, or where a single click
chooses but a double click does not select that item???).

In article <83@sundown.ACA.MCC.COM> grudin@sundown.ACA.MCC.COM (Jonathan Grudin) writes:
>And consistency is often absent in a good design: Consider an efficient
>typewriter keyboard (QWERTY, Dvorak or whichever is your favorite). In what
>sense is it "consistent" with anything other than itself?  

Yes, keyboards are not 'consistent', they are 'standardized'.
Don Norman's book "The Psychology of Everyday Things" goes into many
of these issues, and is very lucid.  The main problem is to
get a 'transparent' interface that the user doesn't really
realize they are using.  Many things lead to this, like 

	- natural mappings (e.g., laying out labels on the screen for 
	  function keys in the same physical layout as the function 
	  keys are on the keyboard);
	- obvious usage (e.g., pictures of buttons to inform the
	  use that you "push" these to get the action);
	- standardization (e.g., keyboards...no "natural mapping"
	  available so define a standard and everyone learns it).

Many more points are made in this book.  While it's written about things
like light switches and doors, every point made is directly
applicable to use interface design too.  Should be required reading
for use interface designers!!!

--Ritchey Ruff			ruffwork@cs.orst.edu