cfa: fCFA – R documentation

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fCFA

Stepwise CFA approaches

Description

These CFA methods detect and eliminate stepwise types/antitypes cells by specifying an appropriate contrast in the design matrix. The procedures stop when model fit is achieved. Functional CFA (fCFA) uses a residual criterion, Kieser-Victor CFA (kvCFA) a LR-criterion.

Usage

fCFA(m.i,  X, tabdim, alpha = 0.05)
kvCFA(m.i, X, tabdim, alpha = 0.05)

Arguments

`m.i`	Vector of observed frequencies.
`X`	Design Matrix of the base model.
`tabdim`	Vector of table dimensions.
`alpha`	Significance level.

Value

`restable`	Fit results for each step
`design.mat`	Final design matrix
`struc.mat`	Structural part of the design matrix for each step
`typevec`	Type or antitype for each step
`resstep`	Design matrix, expected frequency vector, and fit results for each step

Author(s)

Patrick Mair, Alexander von Eye

References

von Eye, A., and Mair, P. (2008). A functional approach to configural frequency analysis. Austrian Journal of Statistics, 37, 161-173.

Kieser, M., and Victor, N. (1999). Configural frequency analysis (CFA) revisited: A new look at an old approach. Biometrical Journal, 41, 967-983.

Examples

#Functional CFA for a internet terminal usage data set by Wurzer 
#(An application of configural frequency analysis: Evaluation of the
#usage of internet terminals, 2005, p.82)
dd <- data.frame(a1=gl(3,4),b1=gl(2,2,12),c1=gl(2,1,12))
X <- model.matrix(~a1+b1+c1,dd,contrasts=list(a1="contr.sum",b1="contr.sum",
    c1="contr.sum"))
ofreq <- c(121,13,44,37,158,69,100,79,24,0,26,3)
tabdim <- c(3,2,2)

res1 <- fCFA(ofreq, X, tabdim=tabdim)
res1
summary(res1)


# Kieser-Vector CFA for Children's temperament data from 
# von Eye  (Configural Frequency Analysis, 2002, p. 192) 
dd <- data.frame(a1=gl(3,9),b1=gl(3,3,27),c1=gl(3,1,27))
X <- model.matrix(~a1+b1+c1,dd,contrasts=list(a1="contr.sum",
    b1="contr.sum",c1="contr.sum"))
ofreq <- c(3,2,4,23,23,6,39,33,9,11,29,13,19,36,19,21,26,18,13,30,
         41,12,14,23,8,6,7)
tabdim <- c(3,3,3)

res2 <- kvCFA(ofreq, X, tabdim=tabdim)
res2
summary(res2)

cfa

Configural Frequency Analysis (CFA)

v0.10-0

GPL (>= 2)

Authors

Patrick Mair [aut, cre], Stefan Funke [aut], Joachim Harloff [ctb], Alexander von Eye [ctb]

Initial release

2017-04-29