How to assign blocks in MCMC chain (Bayesian statistics)

Hi all,

I am new to Bayesian stats so excuse my title if it is incorrect. Basically I need to make a metadata file with all my covariates and a block identifier file. Again, apologies if these are misworded.

I have a dataset of microbiome samples that were taken from three sources. They were also either given Treatment A or control.

Would this be correct for my metadata file? (first row is column headers; sample 1 is first row name; was not sure how to align it up on here)

' Source 1 Source 2 Source 3 Treatment A

sampleA 1 0 0 1

sampleB 0 1 0 0

sampleC 0 0 0 1'

And for my block identifier (without rows names or column headers):

1 4 7 10

2 5 8 11

3 6 9 12

In my actual dataset there are more samples so it might be like 1,1,1,1,2,2,2,2 etc.

But do I have the idea down correctly?

Thank you,