1. B

    Different value of Cronbach's alpha with psych and ltm packages and SPSS

    Hi, I'm trying to look at the internal consistency of a questionnaire consisting of 9 binary items. I mainly use SPSS, but am using R to determine McDonald's Omega coefficient using the omega() function in the "psych" package. The main output I get from the omega function is: Alpha...
  2. P

    How to deal with a bifactor solution with negative loadings on group factors

    I´m a little confused: I tried to calculate a bifactor solution and afterwards omega like in e.g. "The Rediscovery of Bifactor Measurement Models; Multivariate Behavioral Research, Volume 47, Issue 5, 2012" Now some of the...
  3. S

    Answer to Simple Prob Assignment

    This problem concerns MGB Problem 1 of Chapter 1: "One urn contains one black ball and one gold ball. A second urn contains one white and one gold ball. One ball is selected at random form each urn". Exhibit a sample space from this experiment. Why is the answer for omega contains the...