R help - Feb 2010 - mle.stepwise

Hello,

I have a basic question on mle.stepwise, which seems to return  
strange answers, even on a basic example.  I posted this last May but  
never got an answer.  I resend it here hoping it will this time.

# BEGIN

require(wle)
x1 = runif(100)
x2 = runif(100)
y = 3 + 2*x1 + rnorm(100)	

# so x1 is in the model, but not x2

mle.stepwise(y ~ x1 + x2, type = "Backward")		

# Backward selection gets it right, the other two return non-sense

mle.stepwise(y ~ x1 + x2)	
mle.stepwise(y ~ x1 + x2, type = "Stepwise")

# If the variables are entered in a different order, the result changes

mle.stepwise(y ~ x2 + x1)
mle.stepwise(y ~ x2 + x1, type = "Stepwise")

# END

I am running R version 2.10.1 on Mac OS X 10.4.11 and wle 0.9-3.

Any idea?  Help much appreciated.

Thanks,
Ery

eariasca <eariasca <at> math.ucsd.edu> writes:
> 
> Hello,
> 
> I have a basic question on mle.stepwise, which seems to return  
> strange answers, even on a basic example.  I posted this last May but  
> never got an answer.  I resend it here hoping it will this time.
> 
> # BEGIN
> [snip]
> # END
> 
> I am running R version 2.10.1 on Mac OS X 10.4.11 and wle 0.9-3.
> 
> Any idea?  Help much appreciated.
  Perfectly reasonable, reproducible example, but: since this is a
contributed package (and hence less used/fewer people will have an
idea how it is supposed to work) I would suggest you contact the
package author (see help(package="wle") ...)

  Ben Bolker