Questions on categorical data analysis
- How do I explain adding 0.5 to the cells for the odds ratio, d' (dprime) or logit transform? 
- What is heterogeneity of variance in SPSS Probit and Logit (and Poisson) Regressions? 
- What is overdispersion in handling proportions or count data and how do I handle it? 
- How do I perform tests of Marginal Homogeneity between two raters measuring the same items? 
- When should I use a logit analysis as opposed to an arcsine transformed ANOVA? 
- How do I do a matched pairs comparison on dichotomous data using covariates in SPSS? 
- How do I get SPSS to do a Chi-squared analysis of a two-way frequency table? 
- How do I compare a list of observed frequencies with a list of my own expected frequencies? 
- Using a chi-square to see if two or more proportions are equal 
- How do I know which elements contribute to a relationship in a two-way frequency table? 
- When do I use the correction for continuity when performing a chi-square analysis on a 2x2 table? 
- How do I do a linear trend of proportions in a Chi-squared analysis in SPSS? 
- How do I test for the presence of an unknown ordering across subjects using 2 Dimensional data? 
- Improved Confidence Limits for a binomial proportion and differences in binomial proportions 
- How do I compare observed numbers correct to those expected by chance in a multi-choice task? 
- How do I compute a leaving-one-out error rate for a logistic regression in SPSS? 
- Why are the standard errors so large in logistic regression? 
- How do I choose between different logistic regression models? 
- How do I interpret output from a Multinomial logistic regression? 
- How do I plot and interpret a ROC curve in assessing strength in two group prediction?