Gráficos para dados tipo LIKERT

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Gráfico para escala likert

Ideias para Dissertação do Vitor do HVet - AMAN

# É necessário instalar os pacotes a seguir. 
# install.packages("devtools")
# install.packages("plyer")
# library (devtools)
# install_github('likert', 'jbryer')
library(likert)
library(plyr)

# dados do Programme of International Student Assessment PISA
# North American (i.e. Canada, Mexico, and United States) results from the 2009 Programme of International Student Assessment (PISA) as provided by the Organization for Economic Co-operation and Development (OECD). 
# a data frame 66,690 ovservations of 81 variables from North America.
# carrega os dados na memória
data(pisaitems)
# Preparando a base de dados
# o comando substr(names(pisaitems), 1, 5) == "ST25Q"  selecionar somente as colunas com os 5 primeiros caracteres igual a ST25Q
title <- "How often do you read these materials because you want to?"
items29 <- pisaitems[, substr(names(pisaitems), 1, 5) == "ST25Q"]
names(items29) <- c("Magazines", "Comic books", "Fiction", "Non-fiction books", "Newspapers")
likert29 <- likert(items29)
#summary(likert29)
plot(likert29) + ggtitle(title)

#print(items29)
plot(likert29,plot.percents=TRUE) + ggtitle(title)

plot(likert29,plot.percents=F,wrap=30,centered=FALSE) + ggtitle(title)

plot(likert29, centered=FALSE, wrap=30)

likert.bar.plot(likert29,
                wrap=50,
                wrap.grouping = 50,
                centered=T,
                include.center = T,
                plot.percents=T, 
                plot.percent.neutral=F,
                plot.percent.low=F, 
                plot.percent.high=F,
                ordered=T,
                legend = "Respostas") + ggtitle(title)

likert.density.plot(likert29)

likert.heat.plot(likert29)