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Repeated Measures Nested Model in PROC Mixed?

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Hello,



I'm looking for help analyzing data. Here's the experimental setup:



12 experimental plots, divided into 3 blocks. Each block is a factorial combination of two treatments (precipitation, nitrogen).
Within each plot, I have 3-6 trees of species A and 3-6 trees of species B growing.
I measured tree height over time.

So, Block(1,2,3)>plot(pn,Pn,pN,PN)>treeID - Height(continuous response)



I'd like to conduct two sets of analyses:



1) Repeated Measures, Nested Mixed Model with block as a random factor, tree ID nested within plot, and time as the index of repeated measure.

This is the code I've written to attempt this:

PROC MIXED DATA=sgrowth ;
CLASS time plot species precipitation nitrogen treeID block;
MODEL height = species|precipitation|nitrogen|time;
REPEATED time / SUBJECT=treeID TYPE=CS;
RANDOM block block*nitrogen block*precipitation /SUBJECT= plot type=un;
run;

2) a Nested mixed model on data collected at the end of the experiment (no time component)

PROC MIXED data=seedlings ;
CLASS block plot precipitation nitrogen species;
MODEL height=precipitation|nitrogen|species /DDFM=bw;
RANDOM block block*precipitation block*nitrogen/ TYPE=un SUBJECT=plot;
run;

Are these constructed properly? Feedback is greatly appreciated!

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