[R] a question regarding 'lrm'

[Tao Shi]

Hi List,

I don't understand why 'lrm' doesn't recognize the '~.' formula.  I'm pretty sure it was working before. Please see below:

I'm using R2.3.0, WinXP, Design 2.0-12

thanks,
...Tao

> dat <- data.frame(y=factor(rep(1:2,each=50)), x1=rnorm(100), x2=rnorm(100), x3=rnorm(100))
> lrm(y~., data=dat, x=T, y=T)
Error in terms.formula(formula, specials = "strat") : 
        '.' in formula and no 'data' argument
> lrm(y~x1+x2+x3, data=dat, x=T, y=T)

Logistic Regression Model

lrm(formula = y ~ x1 + x2 + x3, data = dat, x = T, y = T)


Frequencies of Responses
 1  2 
50 50 

       Obs  Max Deriv Model L.R.       d.f.          P          C        Dxy      Gamma 
       100      1e-08       3.61          3     0.3066      0.594      0.187      0.188 
     Tau-a         R2      Brier 
     0.095      0.047      0.241 

          Coef     S.E.   Wald Z P     
Intercept -0.05224 0.2071 -0.25  0.8009
x1        -0.30699 0.1952 -1.57  0.1159
x2         0.08093 0.2171  0.37  0.7093
x3         0.21450 0.2247  0.95  0.3398