it seems to me that it's a repeated measure as the exact same people are responding to more than one condition. one can certainly break up the 3 degrees of freedom for "treatments" into the contrasts with one DF for each. but how does one break up the subjects X treatment interaction (DF=21) into separate error terms? if this were a between subject AND a within subjects design, say, where some folks wore type A and others wore type B, you would have separate error terms. i did not know the single error term in the design described could be partitioned. also, subjects are "blocks" you are quite correct. one wants to get the SS for subjects out of the conventional error term for the completely randomized design.
interesting discussion. Paige Miller <[EMAIL PROTECTED]> wrote in message news:<[EMAIL PROTECTED]>... > Bruce Weaver wrote: > > Paige Miller wrote: > > > >> Archana wrote: > > >>> Iam textile engineering looking for some statistical advice. > >>> I have the following test garments (total 4 types)- > >>> > >>> Type A - medium and large > >>> Type B - medium and large > >>> > >>> The same 8 subjects wore the shirts and perfomred some physical > >>> activity. Their heart rate, skin and core temperature etc were > >>> monitored. I want to find out if the heart rate or the other > >>> parameters are significant for the 4 types of shirt. What do i follow? > >>> One way anova or repeated measures design and why? > >> > >> Neither, I think. > >> > >> This is not a one-way ANOVA, as you have three factors (Type A, Type B > >> and subject). Therefore, it should be a three-way ANOVA. I see nothing > >> that would indicate this is a repeated measures design, which to me > >> usually implies repeat measurements over time. Subjects are not a > >> repeated measure, they are a classification variable that is crossed > >> with Type A and Type B. > > > As I understand the original post, the sources of variance in the > > summary table are as follows: > > > > Source df > > ----------- -- > > Between Ss 7 > > Within Ss > > A 1 > > A*S 7 (error term for A) > > B 1 > > B*S 7 (error term for B) > > A*B 1 > > A*B*S 7 (error term for A*B) > > --------- -- > > Total 31 > > > I would call this a 2x2 repeated measures (or within-Ss) design, with > > repeated measures on both A and B. I gather that you would call it > > something else, Paige. Is that right? > > I think it all boils down to terminology differences, as I can't > argue with your ANOVA table. I think of this as a full factorial in > A and B, with a blocking variable named "subject". > > As I said in my first post on this topic, I think of repeated > measures as you apply a "treatment" to an experimental unit, and > then record that experimental unit's value over time. For example, > you give a drug to a subject, then record a measurement of that > subject at 1 day, 2 days, 3 days, ... Perhaps that's an extremely > narrow view of what "repeated measures" is, but that's how I use the > term. > > -- > Paige Miller > Eastman Kodak Company > paige dot miller at kodak dot com > http://www.kodak.com > > "It's nothing until I call it!" -- Bill Klem, NL Umpire > "When you get the choice to sit it out or dance, I hope you dance" > -- Lee Ann Womack . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
