Measures of reader's computer skills

["Snowden, Jim @Cimage" <jims -at- CIMAGE -dot- CO -dot- UK>]

Hi

I'm doing a bit of readership analysis for our next product release, and
I'm finding it hard to think of some measures that I can use for the
different user characteristics. So far, I've been looking at these areas
to build up a profile of the user:

- User types (novice user/experienced user/sysadmin/implementor/etc.)

- Information needs of each type (install/"how to"/background info/error
message meanings/etc.)

- Products used by each user type (unfortunately we have about a
gazillion different products and versions)

- Computer systems available (processor/screen quality/etc.)

- Working environment (office/underwater/etc.)

- Computer skills

The idea is to design on the information structure, content, and media
suitable for the different user types.
Does that seem a reasonable list of things to look at or can you think
of something else?
For the Computer skills bit, I'm finding it hard to think of some good
measures to use (eg to categorize the users' knowledge and experience of
computers), so if you've got some ideas, I'd be glad to hear them.

Finally, despite having been a technical writer for what seems like eons
this is the first time I've really done a comprehensive user analysis -
can anyone suggest some good book or resources for finding out more
about how to do this in a thorough manner (I've got the Hackos Managing
your document projects book, and that helps but doesn't give some of the
detail I'm looking for).

Thanks in advance!!

Jim Snowden

	http://www.documentation.com/, or http://www.dejanews.com/