topic Scree plot from proc corresp in SAS Programming

Scree plot from proc corresp

Nikster101 — Tue, 09 Nov 2021 19:13:07 GMT

Hi there. I want to run a multiple correspondence analysis. I cannot use proc corr as my variables are all categorical. I am using porc corresp but I am unsure of how to generate a scree plot. Below is my code

proc corresp mca data=clean2 dimens=2 outc=newout all;
tables race gender nsfasyn deptname campusname quintile;
run;

What procedure would be better suited for MCA and how do I get a scree plot?

Re: Scree plot from proc corresp

PaigeMiller — Tue, 09 Nov 2021 19:35:06 GMT

I think this is called the Inertia table (and plot) in SAS PROC CORRESP. Please take a look and see if that's what you are looking for.

Also, here's an example where it is calculated https://documentation.sas.com/doc/en/pgmsascdc/9.4_3.4/statug/statug_code_crspex1.htm

Re: Scree plot from proc corresp

Nikster101 — Tue, 09 Nov 2021 19:56:02 GMT

It is not quite what I am looking for. The Plot I need is a scree plot similar to that in principal component analysis with the 'elbow'. This was helpful though as I am now getting the inertia table

Re: Scree plot from proc corresp

ChrisHemedinger — Tue, 09 Nov 2021 20:01:19 GMT

Check out @Rick_SAS post here - it might have some guideposts for you:

https://blogs.sas.com/content/iml/2017/08/02/retain-principal-components.html

Re: Scree plot from proc corresp

PaigeMiller — Tue, 09 Nov 2021 22:12:16 GMT

@Nikster101 wrote:
It is not quite what I am looking for. The Plot I need is a scree plot similar to that in principal component analysis with the 'elbow'. This was helpful though as I am now getting the inertia table

Why is it "not quite" what you are looking for? It seems to me to be exactly what you are looking for.

Re: Scree plot from proc corresp

Nikster101 — Tue, 09 Nov 2021 20:41:14 GMT

Well I need a plot like this,

i.e. A scree plot. I am not unsure of how to generate this plot in the proc corresp function.

Re: Scree plot from proc corresp

PaigeMiller — Tue, 09 Nov 2021 22:05:09 GMT

That's exactly what they give you; except they use bars to represent the value instead of a series of lines to represent the value.

Re: Scree plot from proc corresp

Nikster101 — Tue, 09 Nov 2021 22:40:08 GMT

Yes I understand that, I was just wanting to know if getting an plot representation of it was possible.

Re: Scree plot from proc corresp

PaigeMiller — Tue, 09 Nov 2021 22:42:43 GMT

So form over function? If it isn't a line plot, you can't use it? Even if the information is the same?

There is nothing stopping you from plotting it yourself using PROC SGPLOT and then it can look exactly the way you want it to look.