Structural equation modelling is key to understanding the internal workings of an ecosystem. I wanted to know if it's possible to build a SEM utilising data such as
1. Soil physical and chemical properties
2. Fungal diversity
3. Agronomic trait.
I have some experiences with AMOS for building simple models. However I don't know if this technique or steps are in the right order.
My work plan is
1. PCA to sort the variables (is it alright to combine all the variables?)
2. CFA to reduce redundancy.
3. Pathway analysis.
One factor that I am worried about is the fact that soil data are quantitative in nature, so different parameters will have different values. Will this effect the model? Or do I have to use the assign a score range. Eg
pH: 0-2(assigned a value of 1)
pH: 2-4 (assigned a value of 2)
And so on.
I would be interested in knowing if there are any suggestions or comments on both techniques and steps. Regards.