[R] Dependent Variable in Logistic Regression

[Paul Bernal]

Dear friend,

I am aware that I have a binomial dependent variable, which is covid status
(1 if covid positive, and 0 otherwise).

My question was if R requires to turn a binomial response variable into a
factor or not, that's all.

Cheers,

Paul

El sáb., 1 de agosto de 2020 1:22 p. m., Bert Gunter <bgunter.4567 using gmail.com>
escribió:

> ... 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 using 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 using 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 sáb., 1 de agosto de 2020 12:59 p. m., Bert Gunter <
>>> bgunter.4567 using gmail.com> escribió:
>>>
>>> > 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 using 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 using 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.
>>> >>
>>> >
>>>
>>>         [[alternative HTML version deleted]]
>>>
>>> ______________________________________________
>>> R-help using 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
>>
>> He/Him/His
>>
>

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