2-way ANOVA Lost DFs, missing data

[#1]

Hi,

I am attempting to run an interaction between genotype and environment. My experiment has multiple genotypes that were grown in two environments. All the same genotypes were used in both environments. There was some missing data scattered around my data set but I am unsure if this is the cause. I am new to this and appreciate help.

Thank you!

[#2]

Hi,

It is challenging to diagnose the problem without seeing your data table. Still, this type of error could be due to one Environment category missing entirely. Indeed, the result table shows only one value for the Environment category (Nparm = 1), where you expect two levels based on your description. 

Make sure that your data is configured in a "Tall" format (i.e., Stacked) with one column for Environment (2 levels), One column for Genotype (n levels), and one column for your measurements.

I hope it helps.

Best,

TS

[#3]

Thank you for your response. Before returning here, I discovered the problem. There was one genotype grown only in one of the environments but I did not realize this. I removed it and the problem was immediately fixed for Two-way ANOVA.