Repeated Measures Nested Model in PROC Mixed?

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Repeated Measures Nested Model in PROC Mixed?

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, 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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