Hi, i'm after a bit of stats help from someone a little brighter than me....
So, i've run an experiment as follows (to retain anonymity the types of data/categories have been changed): There were two groups who used system A or system B (i.e. my between groups variable). And i want to investigate the effect on their output score (between 1 and 100) over time. So, i took note of the score at 4 time periods - at the start, after 5 mins, after 10 mins and after 15 mins. So, score was my repeated measure.
I need to analyse this (preferably using R, though SPSS is also available to me), but my sticking point is that i have unequal sample sizes (agh!). So, there were 21 people using system A and 24 people using system B (I didn't design it this way - unfortunately had to discard some data).
So, i think i need to do a one-way repeated measures ANOVA for unequal sample sizes. But how?!?!?
Can anyone give me any hints? I've tried this r tutorial series (http://rtutorialseries.blogspot.com/) which is very helpful, but doesn't quite help me out on the unequal sample sizes - i looked at the unequal size section and the discussion of Type I or Type III confused me no end.
Thanks in advance,
Frog