Re: Grouping and Chunking -- Jared Spool

Harvey,

Thanks much for those guidelines.  They look quite useful.

Just one question .. did he based these guidelines on data, and show the 
relation to the data, or are these based on his experience and intuition?

Len

At 01:26 AM 7/24/00 -0400, Harvey Bingham wrote:
>Jared Spool, in Web Site Usability, A Designer's Guide, copyright 1999
>Morgan Kaufmann Publishers, Inc, ISBN 1-55860-569-X
>
>HB: I paraphrase some of the copyright material. There is much more 
>worth-while
>material in the book.
>
>1. Users don't form mental models of sites, they tend to move on from
>where they are, more often than going back.
>
>HB: As there is so little similarity among sites, and the dwelling during
>many browsing sessions jumps among sites, the value in learning the structural
>model of a site is diminished. A user of a portal site may recall its
>structure, but not likely the structure of the many other visited sites.
>
>2. Chunking
>
>2.1 Use of hierarchy may impose too-general chunk names linked to more
>details. Those generic names may confuse the user, whose target may
>not be obviously contained in any of those chunk names.
>
>2.2. Table of contents structure and substructure can show chunking.
>
>HB: particularly if the table of contents can be collapsed/expanded as
>a dynamic user option, though starting with the collapsed form has the
>same problem with the too-general chunking naming.
>
>2.3. "You are Here" indication within chunking hierarchy, repeating the
>chunk names was not so useful as expected.
>
>3. Link Naming
>
>3.1. "Descriptiveness Aids Prediction" Effective link descriptions allow
>the user to anticipate what the link is about. This verbose approach
>was found effective on the old Edmunds site, pictured in the book as
>having a list of 8 links.
>
>HB: Now
>
>     www.edmunds.com
>
>has been redesigned from a long list into a "contemporary" site, with table
>layout but still most links are well-described, as are the alt texts.
>But my visit left me with two pop-up windows to separately close.
>
>3.2. Ambiguous link names -- Edmund used cross links so that a user that 
>wanders
>astray can get back to the desired place without necessarily backing out.
>
>3.3. Distinctly partition information space. A user may choose by process of
>elimination if none are obviously the proper choice.
>
>3.4. Avoid embedded links in paragraphs. Surrounding text confuses.
>
>3.5. Avoid wrapped (or wrappable under user browser setting) links --
>subject to incomplete selection.
>
>4. Link Targets
>
>4.1. Links with targets within the same page are contrary to user
>expectations. Short individual pages avoid the need for these. A special
>case: an early link to the "content" skipping over a long list of links.
>
>4.2. Links going "off-site" have different navigation models, and can confuse.
>
>5. Readability and the Web
>
>5.1 Testers were given questions and sites to find answers to them.
>
>5.2 Users skim, to eliminate irrelevance to current goal.
>
>5.3 Counter-intuitive result: less readable sites lead to user success
>using them. The Gunning Fog index provides the highest correlation with 
>success
>in using a site. Larger values indicate harder to read -- and hence higher 
>user satisfaction. The Fog index 8-step algorithm is given. Also compared are
>the Flesch Reading Ease and Flesch-Kincaid Grade level indexes.
>
>[HB: I expect the test results are biased by how they chose the users to be
>testers. All had experience using the web. Each tested for only three hours.
>The record does not indicate any other measure of user background.]
>
>6. Afterword:
>
>6.1. I went back and chunked (7 +/- 2) the above. [1]
>
>6.2. There are many other topics discussed in Jared's book. I consider the
>work important, and the reporting well organized. Other usability test
>designs may well differ in the conclusions.
>
>----
>
>[1] We have discussed the number of related ideas that are comprehensible
>in short-term memory. The classic reference is:
>
>The Magical Number Seven, Plus or Minus Two: Some Limits on our
>Capacity for Processing Information
>George A. Miller (1956)
>Harvard University
>First published in Psychological Review, 63, 81-97.
>reproduced with permission, by Stephen Malinowski:
>     http://www.yorku.ca/dept/psych/classics/Miller/
>
>It argues that 7 +/- 2 is the useful range for chunking related concepts.
>
>Regards/Harvey Bingham
>

--
Leonard R. Kasday, Ph.D.
Institute on Disabilities/UAP, and
Department of Electrical Engineering
Temple University 423 Ritter Annex, Philadelphia, PA 19122

kasday@acm.org
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Received on Monday, 24 July 2000 09:57:54 UTC