Creating Composite Variable

Load Packages

Haven

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

Psych

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

Summarytools

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

Import Data

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

Scoring Variable

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)

Extraversion.keys <- make.keys(Extraversion, list(Extraversion=c(1,-2,3,4,-5,6,-7,8)))

Extraversion.scales <- scoreItems (Extraversion.keys, Extraversion)

Extraversion.scores <- Extraversion.scales$scores

dataset$Extraversion <- Extraversion.scores[,]

Extraversion.scales$alpha

      Extraversion
alpha    0.8141661