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Path: utzoo!linus!philabs!seismo!rlgvax!cvl!umcp-cs!mark
From: mark@umcp-cs.UUCP
Newsgroups: net.cog-eng
Subject: Re: A good human-factored user interface for postnews
Message-ID: <3283@umcp-cs.UUCP>
Date: Sat, 22-Oct-83 22:42:31 EDT
Article-I.D.: umcp-cs.3283
Posted: Sat Oct 22 22:42:31 1983
Date-Received: Mon, 24-Oct-83 21:25:58 EDT
References: <464@cbosgd.UUCP>
Organization: Univ. of Maryland, Computer Science Dept.
Lines: 22

More than 7 choices does NOT confuse people, and this is a good
example if when it does not.  The choice of how to distribute
the news is hierarchical, not a random selection of items.
This ordering means that one can actually scan it from top
to bottom and pick the first one that seems right.  Thus
the short-term memory usage is only one item, not hitting
the 5 plus-or-minus 2 limit at all.

However, among choices like "all at&t" and "all north america"
there is not a clear hierarchical relationship.  So the number
of these choices should be less than or equal to 7.

(By the way, supposedly 7 plusorminus 2 was a mistake and 7 is an
upper limit, so the proper chunking figure is 5 plusorminus 2.
This appeared in print somewhere (the 5--of course I have the 7
reference) but I cannot find where.  Can anyone help?
-- 
spoken:	mark weiser
UUCP:	{seismo,allegra,brl-bmd}!umcp-cs!mark
CSNet:	mark@umcp-cs
ARPA:	mark.umcp-cs@CSNet-Relay