commit 44c4a7a7abc782e3e29462f9b6e4ad1faf18a00a
parent da836be5f37fbc90baee74fd260b650f77932a5a
Author: eamoncaddigan <eamon.caddigan@gmail.com>
Date:   Fri, 21 Aug 2015 17:02:07 -0400
Comments and cleanup.
Diffstat:
2 files changed, 7 insertions(+), 13 deletions(-)
diff --git a/Jags-Yord-Xnom1grp-Mnormal.R b/Jags-Yord-Xnom1grp-Mnormal.R
@@ -72,17 +72,7 @@ genMCMC = function( datFrm, yName , qName,
   # Write out modelString to a text file
   writeLines( modelString , con="TEMPmodel.txt" )
   #-----------------------------------------------------------------------------
-  # INTIALIZE THE CHAINS.
-  #   # Initial values of MCMC chains based on data:
-  #   muInit = c( mean(y[x==1]) , mean(y[x==2]) )
-  #   sigmaInit = c( sd(y[x==1]) , sd(y[x==2]) )
-  #   threshInit = 1:(nYlevels-1)+0.5
-  #   threshInit[1] = NA
-  #   threshInit[nYlevels-1] = NA
-  #   # Regarding initial values in next line: (1) sigma will tend to be too big if 
-  #   # the data have outliers, and (2) nu starts at 5 as a moderate value. These
-  #   # initial values keep the burn-in period moderate.
-  #   initsList = list( mu=muInit, sigma=sigmaInit, nuMinusOne=4, thresh=threshInit )
+  # This is where the chains would be initialized, but we'll just let JAGS do it
   initsList = NULL
   #-----------------------------------------------------------------------------
   # RUN THE CHAINS
@@ -181,6 +171,7 @@ plotMCMC = function( codaSamples , datFrm , yName , qName, compVal , #RopeEff=NU
                          xlab=bquote(sigma) , 
                          main=paste("Std. Dev.") , 
                          col="skyblue"  )
+    
     #-----------------------------------------------------------------------------
     # 4. effect size. 
     effectSize = ( mu - compVal ) / sigma
diff --git a/antivax-attitudes.R b/antivax-attitudes.R
@@ -43,16 +43,19 @@ questionnaireData <- expData.clean %>%
   # "tidy" the data
   gather("question", "response", -subject_number, -intervention) %>%
   separate(question, c("interval", "question"), sep = "\\.") %>% 
-  mutate(interval = factor(interval, c("pretest", "posttest"), ordered = TRUE))
+  mutate(interval = factor(interval, c("pretest", "posttest"), ordered = TRUE),
+         question = factor(question))
 
 
 # Some plots --------------------------------------------------------------
 
+# Check out the distribution of responses before and after the intervention
 p1 <- ggplot(questionnaireData, aes(x = question, y = response, fill = interval)) +
   geom_violin() + 
   facet_grid(intervention ~ .)
 print(p1)
 
+# Look at each subject's change for each question
 p2 <- ggplot(questionnaireData, aes(x = interval, y = response, group = subject_number)) + 
   geom_line(alpha = 0.2, position = position_jitter(w = 0.15, h = 0.15)) + 
   facet_grid(intervention ~ question)
@@ -61,7 +64,7 @@ print(p2)
 
 # Bayesian analysis of survey data ----------------------------------------
 
-# For now, we'll just fit one model to all the questions pre-test. 
+# Fit a model to each question using pre-intervention data. 
 modelData <- filter(questionnaireData, interval == "pretest")
 
 source("Jags-Yord-Xnom1grp-Mnormal.R")