[R] Howto calculate MS from a unbalanced data
Ronaldo Reis Jr.
chrysopa at insecta.ufv.br
Tue Mar 25 20:19:11 CET 2003
Hi,
I make a nested lme analysis, it is ok.
The estructure is:
lme(y~x,random=~1|x/animal)
It is no the exactly formula, but the teoretical formula. The real formula
have a new variable with x/animal group.
Now I try to construct a nested lme table like the traditional anova table to
presentation of the data.
---------------------------------------------
| Source | SS | d.f. | MS | F | P |
---------------------------------------------
a 2 1.9 0.1682
b 21
resid 657 var(resid)
---------------------------------------------
Total 2222
---------------------------------------------
For balanced data it is easy to complete. I use:
MSb = var(b)*n + var(resid)
MSa = var(a)*bn + MSb
where:
var(a), var(b) and var(resid) are the variance component get by the
VarCorr(m1).
MSb and MSa are my questions (Mean Square).
n is the number of samples in group x/animal (unbalanced)
b is the number of animal in x (balanced)
Howto calculate the n if it is different for each group?
Exist any other easy form to present the results?
Thanks
Ronaldo
--
Justice always prevails ... three times out of seven!
-- Michael J. Wagner
--
| // | \\ [*****************************][*******************]
|| ( õ õ ) [Ronaldo Reis Júnior ][PentiumIII-600 ]
| V [UFV/DBA-Entomologia ][HD: 30 + 10 Gb ]
|| / \ [36571-000 Viçosa - MG ][RAM: 128 Mb ]
| /(.''`.)\ [Fone: 31-3899-2532 ][Video: SiS620-8Mb ]
||/(: :' :)\ [chrysopa at insecta.ufv.br ][Modem: Pctel-onboar]
|/ (`. `'` ) \[ICQ#: 5692561 ][Kernel: 2.4.18 ]
|| ( `- ) [*****************************][*******************]
||| _/ \_Powered by GNU/Debian W/Sarge D+ || Lxuser#: 205366
More information about the R-help
mailing list