On Thu, 1 Jun 2000, Lance Hoffmeyer wrote:
> I have collected data using a questionnaire with 20 rating scales.
> The respondents were asked to use tick marks to rate the answers so
> there were no anchors.
It may not be possible to answer your query
without more details. I am not visualizing what you are describing.
How did they "use tick marks"? Were the tick marks supplied, or did the
respondents make them? What was the response medium? (E.g., a row of
hyphens from edge to edge of the page, or from left margin to right
margin, or containing exactly 51 hyphens; or a row of hyphens with "+"
signs every 10th place, or a row of hyphens with one blank space between
adjacent hyphens; or a row of dots (periods); or columns rather than
rows; or a horizontal line from margin to margin; etc.)
By "there were no anchors" I take it you mean that neither
qualitative nor quantitative values were supplied on the response medium.
How then did you get the quantities you next report? (Measure in cm, or
mm, or tenths of inches, from the edge of the page, or from the left
margin, or from the left end of the line, ...?)
> ... Some people have minimums of '0' and maximums of '10' while others
> have minimums of '6' and maximums of '68'. I wish to do a factor
> analysis so I need to get everything on the same scale. Initially, I
> thought of row standardizing the data. After thinking about it I am
> not completely certain this solves the scale problem.
I rather suspect it generates new scale problems, mostly.
> My first question is whether row standardization puts all respondents
> data onto the same scale?
Sounds to me rather as though it forces
all responses onto an artificially similar scale. Almost certainly it
will not be "the same" scale, because I can see no way of determining
whether in fact (just for instance) the maximum score for one person is
equivalent to the maximum score for another. If this does not bother
you, go ahead.
[OTOH, if you weren't bothered at the outset by supplying
a wholly unanchored, free-floating response medium (as you claim to have
done), it is hard to imagine your being seriously bothered by little
quibbles of this sort this late in the day.]
> The second question is what would be another technique or a better
> technique to get all data onto the same scale?
Others on the list may be more imaginative than I am. If a "same scale"
(or reasonable facsimile thereof) was not provided to respondents at the
outset, I do not see how one can blithely assume that they would have
been responding on any kind of common scale, let alone derive any kind
of equivalences for translating different respondents' output to some
kind of synonymy.
Unless, of course, there was something about the context that
gave implicit meaning, possibly even anchors of a sort, to the response
medium. If there was, you haven't so far described it.
-- DFB.
------------------------------------------------------------------------
Donald F. Burrill [EMAIL PROTECTED]
348 Hyde Hall, Plymouth State College, [EMAIL PROTECTED]
MSC #29, Plymouth, NH 03264 603-535-2597
184 Nashua Road, Bedford, NH 03110 603-471-7128
===========================================================================
This list is open to everyone. Occasionally, less thoughtful
people send inappropriate messages. Please DO NOT COMPLAIN TO
THE POSTMASTER about these messages because the postmaster has no
way of controlling them, and excessive complaints will result in
termination of the list.
For information about this list, including information about the
problem of inappropriate messages and information about how to
unsubscribe, please see the web page at
http://jse.stat.ncsu.edu/
===========================================================================
