== Questions about multivariate analyses ==


 1. [:FAQ/heterogeneity: What is heterogeneity of variance in SPSS Probit and Logit procedures?]


 1. [:FAQ/SobelTest:How do I test whether one independent variable has an influence on a dependent variable other than via the mediation of a second independent variable? (Sobel Test)]

 1. [:FAQ/Collinearity:What is collinearity in multiple regression, and what do I do about it?]

 1. [:FAQ/condnoR: How do I find the condition number of a matrix using R?]

 1. [:FAQ/RatCaseVar:Is there an optimal ratio of cases to predictor variables I should have before performing a multivariate analysis?]
 
 1. [:FAQ/patternMatrix: Which matrix of loadings do I use doing a principal components extraction or non-PC analysis with a direct oblimin rotation when doing a factor analysis?]

 1. [:FAQ/thresholds: What thresholds should I use for factor loading cut-offs?]

 1. [:FAQ/congruenceC: How do I compare a pair of factor loadings?]

 1. [:FAQ/compare: What is the difference between principal components analysis, principal axis analysis and other factor extraction methods?]

 1. [:FAQ/NoFactors: How many factors should I retain in a factor analysis?]

 1. [:FAQ/Cronbach: A note on Cronbach's Alpha.]

 1. [:FAQ/PlusFac: How do I interpret  variables which load on more than one factor?]

 1. [:FAQ/mds: What is multidimensional scaling and how do I do it?]

 1. [:FAQ/cancorr: What is canonical correlation and where can I use it?]

 1. [:FAQ/MANOVA:When should I use a Multivariate Analysis of Variance (MANOVA)?]

 1. [:FAQ/infmles:Why are the standard errors so large in logistic regression?]

 1. [:FAQ/logrrsq:How do I choose between different logistic regression models?]

 1. [:FAQ/threshold:Which discriminant analysis should I use to obtain thresholds to indicate levels of abnormality using a single variable?]

 1. [:FAQ/structure:How do I assess the importance of variables in a Normal Discriminant analysis?]

 1. [:FAQ/criteria:Can you recommend any two group discriminant diagnostics?]

 1. [:FAQ/NDcasestat:Which output criteria should I use when using the casewise results option with the Normal discriminant method in SPSS?]

 1. [:FAQ/roc:How do I plot and interpret a ROC curve in assessing strength in two group prediction?]

 1. [:FAQ/missing:How do I handle missing data in multivariate analyses in SPSS?]

 1. [:FAQ/cc:How do I find complete cases in SPSS and R?]

 1. [:FAQ/lag:How can I detect identical cases in SPSS without having an ID number?]

 1. [:FAQ/euclid:What is Euclidean distance and how do I compute it?]

 1. [:FAQ/mahal:How do I detect multivariate outliers?]

 1. [:FAQ/sem:Structural equation modelling in R]

 1. [:FAQ/texts: Can you recommend any statistical textbooks?]

 1. [:FAQ/mvnormc: How do I check for multivariate normality?]