R Manual

Loading Packages

haven

if (!require(haven)){
  install.packages("haven", dependencies = TRUE)
  require(haven)
}

psych

if (!require(psych)){
  install.packages("psych", dependencies = TRUE)
  require(psych)
}

dataset <- read_sav("https://osf.io/kd4ej/download")

#create dataframe with only relevant variables to work with
Extraversion <- data.frame (dataset$FFM_1, dataset$FFM_6, dataset$FFM_11, dataset$FFM_16, dataset$FFM_21, dataset$FFM_26, dataset$FFM_31, dataset$FFM_36)

#create list of 'keys'. The numbers just refer to the order of the quetsions in the data.frame () you just made. The most important thing is to mark the questions that should be revered with a '-'
Extraversion.keys <- make.keys(Extraversion, list(Extraversion=c(1,-2,3,4,-5,6,-7,8)))

#score the scale
Extraversion.scales <- scoreItems (Extraversion.keys, Extraversion)

#save the scores
Extraversion.scores <- Extraversion.scales$scores
#save the scores back in 'dataset'
dataset$Extraversion <- Extraversion.scores[,]

Extraversion.scales$alpha

      Extraversion
alpha    0.8141661

summarytools

Installs tools to quickly and neatly summarize data

if (!require(summarytools)){
  install.packages("summarytools", dependencies = TRUE)
  require(summarytools)
}