[R] looping through predictors

[Dimitri Liakhovitski]

Thank you very much- I found ?as.formula of great help!
Dimitri



On Tue, Mar 9, 2010 at 6:36 PM, David Winsemius <dwinsemius at comcast.net> wrote:
> I already answered a very similar question earlier today. It was in the
> context of a question about a different regression function, but the formula
> methods are generic. Look for "Question on passing in parameter to Cox
> hazard".
>
> (That does not mean I approve of such fishing expeditions.)
>
> --
> David.
>
> On Mar 9, 2010, at 6:26 PM, Dimitri Liakhovitski wrote:
>
>> Dear R-ers,
>> I have a data frame data with predictors x1 through x5 and the
>> response variable y.
>> I am running a simple regression:
>>
>> reg<-lm(y~x1, data=data)
>>
>> I would like to loop through all predictors. Something like:
>> predictors<-c("x1","x2",... "x10)
>> for(i in predictors){
>>  reg<-lm(y~i)
>> etc.
>> }
>>
>> But it's not working. I am getting an error:
>> Error in model.frame.default(formula = Y ~ x1 + x2 + x3 + i, data =
>> sample,  :
>>  variable lengths differ (found for 'i')
>>
>> How can I make it take predictor names in the lm formula?
>> Thank you!
>>
>> --
>> Dimitri Liakhovitski
>> Ninah.com
>> Dimitri.Liakhovitski at ninah.com
>>
>
>
> David Winsemius, MD
> West Hartford, CT
>
>



-- 
Dimitri Liakhovitski
Ninah.com
Dimitri.Liakhovitski at ninah.com