Hi On Mon, 25 Feb 2002, Jay Tanzman wrote:
> I just got chewed out by my boss for modelling the means of some 7-point > semantic differential scales. The scales were part of a written, > self-administered questionnaire, and were laid out like this: > > Not stressful 1__ 2__ 3__ 4__ 5__ 6__ 7__ Very stressful > > So, why or why not is it kosher to model the means of scales like this? Two possibilities suggest themselves (there are probably more), although somewhat unclear to me what you mean by "modelling the means." 1. You are aggregating across items that the boss thinks should be analyzed separately, either because they measure different constructs or because some are reverse-worded? 2. Perhaps more likely, your boss may have learned (wrongly?) that parametric stats should not be done unless scales of measurement are at least interval in quality. Search on google for people like John? Gaito and S.S. Stevens and for phrases like "scales of measurement" and "parametric statistics." This debate surfaces now and then, so there are probably things in various archives as well. Best wishes Jim ============================================================================ James M. Clark (204) 786-9757 Department of Psychology (204) 774-4134 Fax University of Winnipeg 4L05D Winnipeg, Manitoba R3B 2E9 [EMAIL PROTECTED] CANADA http://www.uwinnipeg.ca/~clark ============================================================================ ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at http://jse.stat.ncsu.edu/ =================================================================
