What usually should be done with missing values when I am conducting a t test or other tests?

What should I do with the missing values in my data. I ned to perform a t test of two samples to test the mean difference between them. How should I handle them in S-Plus or SAS? Thanks. JJ = Instructions for joining and leaving

Probability --How do I find the conditional distribution?

If we have X and Y 's density function, each with independent distribution, how do I get 1) the conditional distribution of X, given than X>a.(a >0 and is a fixed number) 2) the conditional distribution of X, given that X <= Y.

Composite scale and factor score coefficients

I have a question regarding the creation of an overall scale from several likert-type items. I have a group of items that I'd like to sum to create the scale. Results of a factor analysis show that the items load high on one factor. The items also have a high alpha coefficient. H

Composite scale and factor score coefficients

I have a question regarding the creation of an overall scale from several likert-type items. I have a group of items that I'd like to sum to create the scale. Results of a factor analysis show that the items load high on one factor. The items also have a high alpha coefficient.

comparing dispersion of items with different scales

! These social scientists are far too liberal :) ) Marcelo Jenny Vienna, Austria === This list is open to everyone. Occasionally, less thoughtful people send inappropriate messages. Please DO NOT COMPLAIN TO THE