At 08:57 PM 4/7/02 +0000, Tristan Miller wrote: >Greetings. > >On Sun, 7 Apr 2002, Glen Barnett wrote: > > Assuming you *can* take average student abilities across classes as equal > >Who said that we are sampling across classes? I was thinking of the case >where the assignments from a single large class are randomly divided among >several graders for marking, and one of the graders is an outlier.
say ... you have (just as an example) 50 examinees ... each turning in an assignment ... and, randomly assigning them to 5 graders ... 10 assignments each ... right? how will you know for sure IF a grader is aberrant? ... an outlier? ... surely, across the graders, there will be mean differences in their gradings ... so, how much is now "defined" as too much? if we make some assumption that IF this person is aberrant ...that is a random aberration ... then some linear adjustment might be called for or justified but, if that is not the case ... some peculiar way in which this grader rates things ... either very high or low ... if he/she does it in some strange way DEPENDING on the specific content said by the examinees ... then i don't see that such an across the board adjustment can be justified > > there are a variety of ways you might match mean and s.d., matching by mean and sd ... does not solve the potential problem that the ORDERings of the examinees may be different FOR that set of examinee papers COMPARED to how other graders might have rated these assignments ... >================================================================= >Instructions for joining and leaving this list, remarks about the >problem of INAPPROPRIATE MESSAGES, and archives are available at: >. http://jse.stat.ncsu.edu/ . >================================================================= . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
