topic Re: polycholic correlation using proc corr in New SAS User

polycholic correlation using proc corr

astudent — Tue, 28 Feb 2023 10:34:37 GMT

I have a dataset of 4 independent categorical variables and 1 independent continous variable. I am very new to both SAS and statistics. I am trying to do a polycholic correlation using proc corr statement. the polycholic correlation table is coming out empty. I am trying to determine the effect of the independent variables on the dependent variable. I am looking for insights on how to do this. Here is my code:

PROC CORR data=Home.BaselineCH OUTPLC=home.polyCorr ;

var S1Q2 HEI2010_TOTAL_SCORE;

run;

output:

2 Variables:

S1Q2 HEI2010_TOTAL_SCORE

Polychoric Correlations
Variable	With Variable	N	Correlation	Wald Test	LR Test
Standard Error	Chi-Square	Pr > ChiSq	Chi-Square	Pr > ChiSq
S1Q2	HEI2010_TOTAL_SCORE	174	.	.	.	.	.	.

Re: polycholic correlation using proc corr

PaigeMiller — Tue, 28 Feb 2023 11:12:36 GMT

Do you mean "polychoric" correlation?

Your description of the problem mentions "4 independent categorical variables and 1 independent continous [sic] variable" and later you talk about a dependent variable, which hasn't been mentioned. And you show us a SAS output with just two variables. Could you please clarify?

Re: polycholic correlation using proc corr

ballardw — Tue, 28 Feb 2023 11:55:15 GMT

Show your log. Copy the code and all the notes, warnings or messages from running the code. On the forum open a text box using the </> icon that appears above the message window and paste the text. The text box is to preserve formatting of any diagnostic messages that might appear.

Or show us the result of running this code:

Proc freq data=home.baselinech;
   tables s1q2*hei2010_total_score/ list missing;
run;

Or share your data.

If you don't have at least 2 different values for each variable the polychoric can't be calculated. Which would be seen in the LOG

with a message like

WARNING: The number of groups for variable <variable name> is less than 2, the affected polychoric correlations are set to missing.

Re: polycholic correlation using proc corr

astudent — Tue, 28 Feb 2023 13:55:39 GMT

Here is my code

PROC CORR data=Home.BaselineCH OUTPLC=home.polyCorr;

with HEI2010_TOTAL_SCORE;

var S1Q2;

run;

and this is the my log

<418 PROC CORR data=Home.BaselineCH OUTPLC=home.polyCorr nomiss;

419 with HEI2010_TOTAL_SCORE;

420 var S1Q2;

421 run;

WARNING: The number of groups for variable HEI2010_TOTAL_SCORE is greater than 20, the number in the

NGROUPS= option, the affected polychoric correlations are set to missing.

NOTE: The data set HOME.POLYCORR has 4 observations and 3 variables.

NOTE: PROCEDURE CORR used (Total process time):

real time 0.08 seconds

cpu time 0.06 seconds>

Re: polycholic correlation using proc corr

astudent — Tue, 28 Feb 2023 13:58:13 GMT

My apologies for the confusion. it is 4 independent categorical variables and 1 dependent continous variable