Multiple regression or Two-way ANOVA
Hello!
I have set of data that includes different cell groups, cultured over 16 days. the cell count is measured every 2 days (sampling days)
I'm looking at multiple regression to check the difference in the cell group*sampling days. I have a total of 9 sampling days and 7 cell groups. my problem is that my parameter estimates do not show the last sampling period (eg. cellgroup1*day 16, cellgroup2*d...