topic Re: Binary logistic regression in SAS Studio

Binary logistic regression

laurenhosking — Wed, 08 Jan 2020 14:34:10 GMT

I want to create a logistic model to predict the body fat group i.e. lean or bulky. Select the significant variables, check all the criteria to analyse your model and make an sensitivity-specificity analysis. However I’m unsure what my classification or continuous varible would be or if I’d have any

Re: Binary logistic regression

PaigeMiller — Wed, 08 Jan 2020 14:43:22 GMT

You have to use independent variables to do any prediction. Do you have independent variables? What are they?

Re: Binary logistic regression

laurenhosking — Wed, 08 Jan 2020 15:14:06 GMT

I m given variables including sport (basketball, cross-country, track, softball, volleyball, swim & tennis), height, weight, percentage body fat, BMI (body mass index), sit ups per minute, 40 yard dash, vertical jump, sit reach test, bench press (60lbs and max), leg press (200lbs and max), medicine ball throw and shuttle run.

Re: Binary logistic regression

PaigeMiller — Wed, 08 Jan 2020 15:16:58 GMT

So that list contains the independent variables you could put into your model. Sport seems to be the only categorical variable in the list.

Re: Binary logistic regression

laurenhosking — Wed, 08 Jan 2020 15:26:41 GMT

So are these variables classed as continuous variables or classification variables?

Re: Binary logistic regression

laurenhosking — Wed, 08 Jan 2020 15:28:13 GMT

I also made a variable based on body fat which I know is the response

Re: Binary logistic regression

PaigeMiller — Wed, 08 Jan 2020 15:28:40 GMT

Categorical variables (like sport) are also considered to be classification variables (and you would use the CLASS statement when you do the model). The rest seem to be continuous, but since I don't have your data, you have to look at the data and confirm that.

Re: Binary logistic regression

laurenhosking — Wed, 08 Jan 2020 15:56:53 GMT

They are independent however I am very confused how to carry out this test

Re: Binary logistic regression

PaigeMiller — Wed, 08 Jan 2020 16:06:45 GMT

Here's an example using PROC LOGISTIC

https://documentation.sas.com/?cdcId=pgmsascdc&cdcVersion=9.4_3.4&docsetId=statug&docsetTarget=statug_logistic_examples02.htm&locale=en

Re: Binary logistic regression

laurenhosking — Wed, 08 Jan 2020 17:44:24 GMT

Thank you! Would you say to include every one of the independent variables?

Re: Binary logistic regression

PaigeMiller — Wed, 08 Jan 2020 17:47:55 GMT

The answer depends on the data.

Re: Binary logistic regression

laurenhosking — Wed, 08 Jan 2020 21:06:30 GMT

Tgis is my data it goes down to 57 entries but

Re: Binary logistic regression

laurenhosking — Wed, 08 Jan 2020 18:53:51 GMT

@Rick_SAS

Re: Binary logistic regression

PaigeMiller — Wed, 08 Jan 2020 20:18:32 GMT

No, I didn't mean you should show me the data, I meant you have to analyze the data and see what variables belong in the model.