5
votes
2answers
4k views

What to do when assumptions are not met in a chi squared test?

I am doing an analysis on a “a priori segmentation”. In order to examine significant differences between the two segments crosstabs and the chi-square test were used. Type of variables: categorical ...
6
votes
2answers
832 views

When is it acceptable to use only two items (variables) per factor in factor analysis?

I have a set of 20 variables that I have put through factor analysis in SPSS. For purposes of the research, I need to develop 6 factors. SPSS has shown that 8 variables (out of 20) have been loading ...
0
votes
2answers
529 views

Cox-regression model: question about acceptability, meaning, & reporting

Apologize for insufficient info in my previous version of this question. So, I am comparing patient survival in a retrospective study between two different groups, using SPSS. Now the difference came ...
7
votes
3answers
1k views

Multinomial logistic regression assumptions

What are the proper assumptions of Multinomial Logistic Regression? And what are the best tests to satisfy these assumptions using SPSS 18?
7
votes
2answers
4k views

How to test for normality in a 2x2 ANOVA?

Study Design: I showed participants some information about sea-level rise, focusing the information in different ways, both in terms of the time-scale and the magnitude of potential rise. Thus I had a ...
7
votes
2answers
6k views

Understanding repeated measure ANOVA assumptions for correct interpretation of SPSS output

I am investigating whether different reward conditions may affect task performance. I have data from a small study with two groups, each with n=20. I collected data on a task that involved performance ...
4
votes
2answers
2k views

Checking factor / covariate independence in ANCOVA

One of the ANCOVA assumptions, as I read it here, says that: Independent variables orthogonal to covariates. In traditional ANCOVA, the independents area assumed to be orthogonal to the factors. If ...