Cronbach Coefficient Alpha

SAS’s proc cor procedure produces two types of cronbach coefficient alpha: raw value and standardized value.

proc corr alpha data=dataname_here;
var  item1 item2 item3 item4 item5 item6 item7;
run;

The result table includes two values:

Cronbach Coefficient Alpha

Variables Alpha
——————————–
Raw 0.74
Standardized 0.75

Standardized version is based on standardized values of all variables included in the analysis.  If you standardize the variables yourself by creating z-score version of items and apply the same procedure, you will get the same value for both raw and standardized values.

proc standardize data=dataname_here out=dataname_here_B mean=0 std=1;
var  item1 item2 item3 item4 item5 item6 item7;
run;
proc corr alpha data=dataname_here_B;
var  item1 item2 item3 item4 item5 item6 item7;
run;

Cronbach Coefficient Alpha

Variables Alpha
——————————–
Raw 0.75
Standardized 0.75