[R] Dependent Variable in Logistic Regression

Bert Gunter
2020-08-01T18:11:15Z

You appear to be confusing a binomial **response** with categorical
"dependent variables." glm() of course fits continuous or categorical
dependent variables. If a continuous dependent variable has only 2 values,
the results for glm() will be the same whether or not it is considered to
be continuous or categorical, though you may not recognize it as such.

This discussion has already wandered off topic to statistical issues. I
will not comment further on or off list. I suggest you consult a good
reference on linear/generalized linear models or talk with a local
statistician.

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 11:04 AM 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]]
>>>
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