library(tidyverse)
library(likert)

data(pisaitems)

# selezioniamo una sola scala come esempio
items24 <- pisaitems %>% 
  select_at(vars(starts_with("ST24Q")))

# nomi degli items
names(items24) <- c(ST24Q01="only if I have to",
                    ST24Q02="one of my favorite hobbies",
                    ST24Q03="like talking about b",
                    ST24Q04="hard to finish b",
                    ST24Q05="happy receving b as a present.",
                    ST24Q06="a waste of time",
                    ST24Q07="enjoy bookstore",
                    ST24Q08="to get information",
                    ST24Q09="cannot sit still and read",
                    ST24Q10="like express opinions about b",
                    ST24Q11="like exchange b")

likert(items24)

l24 <- likert(items24)
str(l24)

summary(l24)

## # qui non ha senso, perché le alternative sono solo 4
## summary(l24, center = 2)

summary(l24) %>% 
  LabRS::kabbit(digits = 2, 
                col.names = c("Item", "basso", "neutro", "alto", "media", "sd"),
                caption = "Statistiche riassuntive: output"
                )

plot(l24)

# con colori e titolo
col <- colorRampPalette(c("pink", "white", "blue"))(4)
plot(l24, colors=col) +
  labs(title = "Reading Attitudes")

plot(l24, type='heat', wrap=30, text.size=3.5)

# variabile di raggruppamento
l24g <- likert(items24, grouping=pisaitems$CNT)

summary(l24g) %>% head()

summary(l24g) %>% 
  filter(Group == "Mexico")

summary(l24g) %>% 
  arrange(Group, desc(high)) %>% 
  head()

plot(l24g, group.order=c('Mexico', 'Canada', 'United States'))