[R] Dependent Variable in Logistic Regression

Bert Gunter
2020-08-01T18:22:20Z

... yes, but so does lm() for a categorical **INdependent** variable with
more than 2 numerically labeled levels. n levels  = (n-1) df for a
categorical covariate, but 1 for a continuous one (unless more complex
models are explicitly specified of course). As I said, the OP seems
confused about whether he is referring to the response or covariates. Or
maybe he just made the same typo I did.

Bert Gunter

"The trouble with having an open mind is that people keep coming along and
sticking things into it."
-- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )


On Sat, Aug 1, 2020 at 11:15 AM Patrick (Malone Quantitative) <
malone at malonequantitative.com> wrote:

> No, R does not. glm() does in order to do logistic regression.
>
> On Sat, Aug 1, 2020 at 2:11 PM Paul Bernal <paulbernal07 at
gmail.com> wrote:
>
>> Hi Bert,
>>
>> Thank you for the kind reply.
>>
>> But what if I don't turn the variable into a factor. Let's say
that in
>> excel I just coded the variable as 1s and 0s and just imported the
dataset
>> into R and fitted the logistic regression without turning any
categorical
>> variable or dummy variable into a factor?
>>
>> Does R requires every dummy variable to be treated as a factor?
>>
>> Best regards,
>>
>> Paul
>>
>> El s?b., 1 de agosto de 2020 12:59 p. m., Bert Gunter <
>> bgunter.4567 at gmail.com> escribi?:
>>
>> > x <- factor(0:1)
>> > x <- factor("yes","no")
>> >
>> > will produce identical results up to labeling.
>> >
>> >
>> > Bert Gunter
>> >
>> > "The trouble with having an open mind is that people keep
coming along
>> and
>> > sticking things into it."
>> > -- Opus (aka Berkeley Breathed in his "Bloom County"
comic strip )
>> >
>> >
>> > On Sat, Aug 1, 2020 at 10:40 AM Paul Bernal <paulbernal07 at
gmail.com>
>> > wrote:
>> >
>> >> Dear friends,
>> >>
>> >> Hope you are doing great. I want to fit a logistic regression
in R,
>> where
>> >> the dependent variable is the covid status (I used 1 for covid
>> positives,
>> >> and 0 for covid negatives), but when I ran the glm, R
complains that I
>> >> should make the dependent variable a factor.
>> >>
>> >> What would be more advisable, to keep the dependent variable
with 1s
>> and
>> >> 0s, or code it as yes/no and then make it a factor?
>> >>
>> >> Any guidance will be greatly appreciated,
>> >>
>> >> Best regards,
>> >>
>> >> Paul
>> >>
>> >>         [[alternative HTML version deleted]]
>> >>
>> >> ______________________________________________
>> >> R-help at r-project.org mailing list -- To UNSUBSCRIBE and
more, see
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>> >> PLEASE do read the posting guide
>> >> http://www.R-project.org/posting-guide.html
>> >> and provide commented, minimal, self-contained, reproducible
code.
>> >>
>> >
>>
>>         [[alternative HTML version deleted]]
>>
>> ______________________________________________
>> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide
>> http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>>
>
>
> --
> Patrick S. Malone, Ph.D., Malone Quantitative
> NEW Service Models: http://malonequantitative.com
>
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