Using R and RStudio for Data Management, Statistical Analysis, and Graphics, 2nd Edition

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“K23166” — 2015/1/28 — 9:35 — page 101 — #127

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7.7. COMPLEX SURVEY DESIGN 101

library(MASS)

ngroups = length(levels(group))

ldamodel = lda(y ~ x1 + ... + xk, prior=rep(1/ngroups, ngroups))

print(ldamodel)

7.6.5 Latent class analysis

Latent class analysis is a technique used to classify observations based on patterns of cate-

gorical responses.

library(poLCA)

poLCA(cbind(x1, x2, ..., x3) ~ 1, maxiter=50000, nclass=k, nrep=n, data=ds)

Note: In this example, a k class model is fit. The poLCA() function requires that the

variables are coded as positive integers. Other support for latent class models can be found

in the randomLCA and the MplusAutomation ...