I have a problem with an unbalanced ANOVA design and wasn't able to solve it through research on the Internet yet. In a lot of questions, when people are talking about their unbalanced designs, it's about different sample sizes or similar. My problem, however, is in the factors itself:
In theory, I have a 3x3 design but on two factors, there are only two repeats possible. So, let's say we have a factor1 (=f1) and factor2 (=f2) that have three levels each, then only the following combinations are possible:
f1-level1 x f2-level1;
f1-level1 x f2-level2;
f1-level1 x f2-levek3;
f1-level2 x f2-level1;
f1-level2 x f2-level2;
f1-level3 x f2-level2;
f1-level3 x f2-level3.
Unfortunately, this is nothing, I can change or avoid by design. Is it possible to reasonably analyse this in ANOVA style or mixed effect models? How do I approach implementing these in SPSS or R?
I am very grateful for every single response. I'm really stuck and after reading a lot on other people's questions, also slightly confused.
Thank you very much in advance!