Created
December 19, 2012 16:24
-
-
Save dsparks/4337992 to your computer and use it in GitHub Desktop.
Latent class model of ANES respondents
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
doInstall <- TRUE | |
toInstall <- c("ggplot2", "poLCA", "reshape2") | |
if(doInstall){install.packages(toInstall, repos = "http://cran.us.r-project.org")} | |
lapply(toInstall, library, character.only = TRUE) | |
ANES <- read.csv("http://www.oberlin.edu/faculty/cdesante/assets/downloads/ANES.csv") | |
ANES <- ANES[ANES$year == 2008, -c(1, 11, 17)] # Limit to just 2008 respondents, | |
head(ANES) # remove some non-helpful variables | |
# Adjust so that 1 is the minimum value for each variable: | |
ANES <- data.frame(apply(ANES, 2, function(cc){ cc - min(cc, na.rm = T) + 1 })) | |
# Estimate latent class model | |
lcFormula <- cbind(cohort, female, race6, religion, pid7, trust, ideo7, inerrant, south) ~ 1 | |
lcModel <- poLCA(lcFormula, ANES, nclass = 4, | |
maxiter = 10000) # Make sure MAX LIKE is found. | |
plot(lcModel) # poLCA-style 3-D plot. | |
# Make a cleaner plot, first easily converting a list to a DF with melt(): | |
lcModelProbs <- melt(lcModel$probs) | |
# Replicating the poLCA 3-D plot, without the 3-D: | |
zp1 <- ggplot(lcModelProbs, | |
aes(x = L1, y = value, fill = Var2)) | |
zp1 <- zp1 + geom_bar(stat = "identity", position = "stack") | |
zp1 <- zp1 + facet_wrap(~ Var1) | |
print(zp1) | |
# Suggested alternative, as a possible improvement: | |
zp2 <- ggplot(lcModelProbs, | |
aes(x = Var1, y = value, fill = Var2)) | |
zp2 <- zp2 + geom_bar(stat = "identity", position = "stack") | |
zp2 <- zp2 + facet_wrap(~ L1) | |
zp2 <- zp2 + scale_x_discrete("Class", expand = c(0, 0)) | |
zp2 <- zp2 + scale_y_continuous("Proportion", expand = c(0, 0)) | |
zp2 <- zp2 + scale_fill_discrete("Factor Level") | |
zp2 <- zp2 + theme_bw() | |
print(zp2) |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
I love this thread and am trying to crib from it. But the line
lcModelProbs <- melt(lcModel$probs, level=2) #[with or without the ", level=2"]
consistently produces the error: "no applicable method for 'melt' applied to an object of class "list""
Any thoughts would be greatly appreciated :)