@mahdiamah wrote: Dear ballardw, I am very thankful for your help.  Since my response is ordinal,how can i change the type of my variables? Data entry was done in SPSS software. Is there any way to change variable type in SAS or other software?   Typically the SAS modeling procedures have a value you supply as a dependent variable along with independent variables and you are attempting to fit parameters with those independent variables that give you the "best" approach to approximating the dependent values.   So if you don't have any actual dependent value what are you modeling??? There isn't a question of "change variable type" as you haven't identified any variable that may need to change type (I don't think that is needed). I would expect a variable on the Model statement to possibly indicate the number of successful trials of attempts, or a measurement value under different conditions or some similar "result".         ... View more