I need to run a two-way ANOVA (and have the data for it) but I don't get an ANOVA output?
Jul 26, 2020 9:28 AM
| Last Modified: Jul 26, 2020 11:15 AM(314 views)
I need to run a Two-Way ANOVA in order to test concentration by species on germination. I have data and data arrangements very similar to that of videos of Two-Way ANOVA tutorials, however my output is baffling. I attached the output below. Any advice on how to run this would be much appreciated!
As far as what the data set represents, I have extracts from eight grass species at four concentrations (1.87g, 3.75g, 7.5g, and 15g/25ml) and total germination. I wish to test the effect of species by concentration on germination.
You have over-specified your model. This will result in the Singularity Details. If you attach the actual data set or some fake numbers with the rest of the data set, we can come up with the correct model for you. As an aside, you should know the model you want to investigate before collecting the data.
Thanks for your help! I got the experimental design cleared but didn't know enough about statistics at the time to even know what a statistical model would be. I've attached the large dataset and the condensed data set. The the first three columns in condensed data set are the ones I'd like to test. The other columns in the condensed data set are just breakdowns of the first three columns (or the same data broken into percentages).
The "statistical model" is simply a mathematical equation in the form of some polynomial (e.g., Y=f(x)) that describes the relationships between response variables and input variables. Typically you will describe a model and then collect data that allows you to test the model.
I attached the condensed version of your data set and added 2 fit model scripts. You have 1 variable that is categorical (nominal) and one that could be treated as continuous or nominal. I saved fit models for treating the second variable as both continuous and nominal. You will see the associated ANOVA tables.