Implements the criterion-related profile analysis described in Davison & Davenport (2002).
cpa(formula, data, k =100, na.action ="na.fail", family ="gaussian", weights =NULL)
Arguments
formula: An object of class formula of the form response ~ terms.
data: An optional data frame, list or environment containing the variables in the model.
k: Corresponds to the scalar constant and must be greater than 0. Defaults to 100.
na.action: How should missing data be handled? Function defaults to failing if missing data are present.
family: A description of the error distribution and link function to be used in the model. See family.
weights: An option vector of weights to be used in the fitting process.
Returns
An object of class critpat is returned, listing the following components:
lvl.comp - the level component
pat.comp - the pattern component
b - the unstandardized regression weights
bstar - the mean centered regression weights
xc - the scalar constant times bstar
k - the scale constant
Covpc - the pattern effect
Ypred - the predicted values
r2 - the proportion of variability attributed to the different components
F.table - the associated F-statistic table
F.statistic - the F-statistics
df - the df used in the test
pvalue - the p-values for the test
Details
The cpa function requires two arguments: criterion and predictors. The function returns the criterion-related profile analysis described in Davison & Davenport (2002). Missing data are presently handled by specifying na.action = "na.omit", which performs listwise deletion and na.action = "na.fail", the default, which causes the function to fail. The following S3 generic functions are available: summary(),anova(), print(), and plot(). These functions provide a summary of the analysis (namely, R2 and the level a nd pattern components); perform ANOVA of the R2 for the pattern, the level, and the overall model; provide output similar to lm(), and plots the pattern effect.
Examples
## Not run:data(IPMMc)mod <- cpa(R ~ A + H + S + B, data = IPMMc)print(mod)summary(mod)plot(mod)anova(mod)## End(Not run)
References
Davison, M., & Davenport, E. (2002). Identifying criterion-related patterns of predictor scores using multiple regression. Psychological Methods, 7(4), 468-484. DOI: 10.1037/1082-989X.7.4.468.