Dear All,
Apologies if this is too simple a question for the list, but I would
very much appreciate any advice you can give.
A colleague of mine has a data set which is the proportion that
various items are chosen from a list. Results were obtained from
subjects on four different occasions. There was a control and an
‘intervention’ group.
My colleague wishes to use repeated measures ANOVA to determine
whether item by item there are changes in the choices made with time
and whether the changes differ between control and intervention
groups
The data however is extremely non-normal, mostly due to the fact that
for every item on the list the modal value is zero on each occasion.
I’ve tried, to no avail, to normalise the data using a range of
transformations including arcsine – square root.
So the question, how should I proceed with the analysis from here?
Once again apologies if this question is too basic.
Thanks
Graham
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Dr G.S.Clarke Dr G S Clarke
Lecturer in Physiology Darlithydd mewn Ffisioleg
& Biometry a Biometreg
UWB Teaching Fellow Cymrawd Addysgu PCB
School Of Healthcare Sciences Ysgol Gwyddorau Gofal Iechyd
College of Health Coleg Gwyddorau Iechyd
& Behavioural Sciences ac Ymddygiad
University of Bangor Prifysgol Bangor
Fron Heulog Fron Heulog
Ffriddoedd Road Ffordd Ffriddoedd
Bangor Bangor
Gwynedd LL57 2EF Gwynedd LL57 2EF
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