[R-sig-ME] scope for LHS of formula in lmList

[Ken Knoblauch]

Hi,

I have a data frame

  str(Context)
'data.frame':	120 obs. of  4 variables:
  $ Obs     : Factor w/ 6 levels "A","B","C","D",..: 1 1 1 1 1 1 1 1 1 1 ...
  $ TargCntr: num  0 0.002 0.004 0.006 0.008 0 0.002 0.004 0.006 0.008 ...
  $ NumYes  : int  0 0 5 18 23 24 22 22 22 24 ...
  $ NumNo   : int  24 24 19 6 1 0 2 2 2 0 ...

and find that if I run lmList as follows, I get an error message
in which names from the data frame are not found if enclosed in
a cbind for the LHS of formula (for a binomial family)

lmList(cbind(NumYes, NumNo) ~ TargCntr | Obs,
	data = Context, family = binomial)
Error in cbind(NumYes, NumNo) : object 'NumYes' not found
...

but it works fine if I either define a 2 column matrix in my
workspace or add one to the data frame.

resp <- with(Context, cbind(NumYes, NumNo))

lmList(resp ~ TargCntr | Obs, Context, binomial)

Call: lmList(formula = resp ~ TargCntr | Obs, data = Context, family =  
binomial)
Coefficients:
   (Intercept) TargCntr
A  -0.8574118 369.1977
B  -0.8048122 425.1355
  ...

or

Context <- within(Context, Resp <- cbind(NumYes, NumNo))

lmList(Resp ~ TargCntr | Obs, Context, binomial)

Call: lmList(formula = Resp ~ TargCntr | Obs, data = Context, family =  
binomial)
Coefficients:
   (Intercept) TargCntr
A  -0.8574118 369.1977
B  -0.8048122 425.1355
  ...

So, there is an easy workaround.  I've mostly been working
with binary responses lately, so hadn't noticed this behavior
earlier.

sessionInfo()
R version 2.11.1 Patched (2010-08-30 r52847)
Platform: i386-apple-darwin9.8.0/i386 (32-bit)

locale:
[1] en_US.UTF-8/en_US.UTF-8/C/C/en_US.UTF-8/en_US.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods
[7] base

other attached packages:
[1] lme4_0.999375-35   Matrix_0.999375-44 lattice_0.19-11

loaded via a namespace (and not attached):
[1] grid_2.11.1   MASS_7.3-7    nlme_3.1-96   stats4_2.11.1
[5] tools_2.11.1

Thank you.

best,

Ken

-- 
Ken Knoblauch
Inserm U846
Stem-cell and Brain Research Institute
Department of Integrative Neurosciences
18 avenue du Doyen Lépine
69500 Bron
France
tel: +33 (0)4 72 91 34 77
fax: +33 (0)4 72 91 34 61
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http://www.sbri.fr/members/kenneth-knoblauch.html