At 07:37 AM 2/28/02 -0800, Brad Anderson wrote: >I think a lot of folks just run standard analyses or arbitrarily apply >some "normalizing" transformation because that's whats done in their >field. Then report the results without really examining the >underlying distributions. I'm curious how folks procede when they >encounter very goofy distrubions. Thanks for your comments.
i think the lesson to be gained from this is that, we seem to be focusing on (or the message that students and others get) getting the analysis DONE and summarizied ... and with most standard packages ... that is relatively easy to do for example, you talk about a simple regression analysis and then show them in minitab that you can do that like: mtb> regr 'height' 1 'weight' and, when they do it, lots of output comes out BUT, the first thing is the best fitting straight line equation like: The regression equation is Weight = - 205 + 5.09 Height and THAT's where they start AND stop (more or less) while software makes it rather easy to do lots of prelim inspection of data, it also makes it very easy to SKIP all that too before we do any serious analysis ... we need to LOOK at the data ... carefully ... make some scatterplots (to check for outliers, etc.), to look at some frequency distributions ON the variables, to even just look at the means and sds ... to see if some serious restriction of range issue pops up ... THEN and ONLY then, after we get a feel for what we have ... THEN and ONLY then should we be doing the main part of our analysis ... ie, testing some hypothesis or notion WITH the data (actually, i might call the prelims the MAIN part but, others might disagree) we put the cart before the horse ... in fact, we don't even pay any attention to the horse unfortunately, far too much of this is "caused" by the dominant and preoccupation of doing "significance tests" so we run routines that give us these "p values" and are done with it ... without paying ANY attention to just looking at the data my 2 cents worth >================================================================= >Instructions for joining and leaving this list, remarks about the >problem of INAPPROPRIATE MESSAGES, and archives are available at > http://jse.stat.ncsu.edu/ >================================================================= Dennis Roberts, 208 Cedar Bldg., University Park PA 16802 <Emailto: [EMAIL PROTECTED]> WWW: http://roberts.ed.psu.edu/users/droberts/drober~1.htm AC 8148632401 ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at http://jse.stat.ncsu.edu/ =================================================================
