On Tue, 24 Oct 2000 08:37:10 -0400 "John W. Kulig"
<[EMAIL PROTECTED]> wrote:
> Supposedly, it is tricky (or, downright wrong) to use these scales for
> across group comparisons, they are only for within-group comparisons. The
> reason is that different groups' use of the adjectives may not be
> equivalent. If we compare "tasters" versus "nontasters" for instance, the
> the anchor "extremely bitter" for the former may correspond to a very
> intense stimulus - subjectively as intense as a very loud noises. For the
> latter, an "extremely bitter" taste may be at the top of gustatory
> experiences - but relatively mild relative to very loud noises. That is, the
> sensory world of tasters vs. nontasters guarantees these adjectives will be
> interpreted differently. The same logic would apply to other between-group
> comparisons.
I agree, but the major problem here is caused by comparing
across nonequivalent groups.
I see this problem ignored most often when people are talking
about "gender differences." Consider the following
stem-and-leaf plots of answers to the question---
Is "Doom" a gory computer game?
1 2 3 4 5 6 7
Not Very Medium Very
Men Women
7 7 +++
6 +++ 6 +++++++
5 +++++++ 5 ++++++++++
4 ++++++++++ 4 ++++++
3 ++++++ 3 ++
2 ++ 2 +
1 + 1
Notice that the distribution of Men's answers are shifted
towards "Not" by 1 item but are otherwise identical to the
Women's answers.
It doesn't matter whether you treat the data as interval or
ordinal (the usual argument involving Likert-type scales). The
summary statistic would indicate that men rate the game as less
gory.
As John indicated, the problem with this conclusion is that we
don't know whether males and females use the scales in the same
manner. The difference may only mean that men and women have a
systematically different definition of the words "not very."
Ken
----------------------
Kenneth M. Steele [EMAIL PROTECTED]
Dept. of Psychology
Appalachian State University
Boone, NC 28608
USA
