Esercitazione Completa

Autore/Autrice

Ottavia e Margherita

1 MACH-IV

I dati di questo questionario vengono dal sito OpenPsychometrics. Questio questionario è stato sviluppato per la misura del Machiavellisimo, definto come segue in Christie & Geis (1970):

[MAchiavelism is] a tendency to manipulate others for personal gain, accompanied by a lack of concern for conventional morality, low emotional involvement in interpersonal relations, and a cynical view of human nature.

Di seguito, il codebook associato ai dati:

This data was collected using an online version of the MACH-IV developed by Richard Christie and Florence L. Geis. See Christie, R. & Geis, F. (1970) "Studies in Machiavellianism". NY: Academic Press.

Data collection took place July 2017 - March 2019.

The main body of the consisted of 20 questions. The text of those questions is below.

{
"Q1" : "Never tell anyone the real reason you did something unless it is useful to do so.",
"Q2" : "The best way to handle people is to tell them what they want to hear.",
"Q3" : "One should take action only when sure it is morally right.",
"Q4" : "Most people are basically good and kind.",
"Q5" : "It is safest to assume that all people have a vicious streak and it will come out when they are given a chance.",
"Q6" : "Honesty is the best policy in all cases.",
"Q7" : "There is no excuse for lying to someone else.",
"Q8" : "Generally speaking, people won't work hard unless they're forced to do so.",
"Q9" : "All in all, it is better to be humble and honest than to be important and dishonest.",
"Q10" : "When you ask someone to do something for you, it is best to give the real reasons for wanting it rather than giving reasons which carry more weight.",
"Q11" : "Most people who get ahead in the world lead clean, moral lives.",
"Q12" : "Anyone who completely trusts anyone else is asking for trouble.",
"Q13" : "The biggest difference between most criminals and other people is that the criminals are stupid enough to get caught.",
"Q14" : "Most people are brave.",
"Q15" : "It is wise to flatter important people.",
"Q16" : "It is possible to be good in all respects.",
"Q17" : "P.T. Barnum was wrong when he said that there's a sucker born every minute.",
"Q18" : "It is hard to get ahead without cutting corners here and there.",
"Q19" : "People suffering from incurable diseases should have the choice of being put painlessly to death.",
"Q20" : "Most people forget more easily the death of their parents than the loss of their property."
}

The questions were presented one at a time in a random order. Users responded to each item on a five point scale: 1=Sisagree, 2=Slightly disagree, 3=Neutral, 4=Slightly agree, 5=Agree.

Three values are recorded for each question. e.g.

Q1A - the user's answer
Q1I - the position of that item in the survey
Q1E - the time spend on that question in milliseconds

After the test body, users were asked if they would be willing to complete an additional research survey. This data only includes those who agreed to.

The optional survey included a variety of questions:

The Ten Item Personality Inventory was administered (see Gosling, S. D., Rentfrow, P. J., & Swann, W. B., Jr. (2003). A Very Brief Measure of the Big Five Personality Domains. Journal of Research in Personality, 37, 504-528.):

TIPI1   Extraverted, enthusiastic.
TIPI2   Critical, quarrelsome.
TIPI3   Dependable, self-disciplined.
TIPI4   Anxious, easily upset.
TIPI5   Open to new experiences, complex.
TIPI6   Reserved, quiet.
TIPI7   Sympathetic, warm.
TIPI8   Disorganized, careless.
TIPI9   Calm, emotionally stable.
TIPI10  Conventional, uncreative.

The TIPI items were rated "I see myself as:" _____ such that

1 = Disagree strongly
2 = Disagree moderately
3 = Disagree a little
4 = Neither agree nor disagree
5 = Agree a little
6 = Agree moderately
7 = Agree strongly


The following items were presented as a check-list and subjects were instructed "In the grid below, check all the words whose definitions you are sure you know":

VCL1    boat
VCL2    incoherent
VCL3    pallid
VCL4    robot
VCL5    audible
VCL6    cuivocal
VCL7    paucity
VCL8    epistemology
VCL9    florted
VCL10   decide
VCL11   pastiche
VCL12   verdid
VCL13   abysmal
VCL14   lucid
VCL15   betray
VCL16   funny

A value of 1 is checked, 0 means unchecked. The words at VCL6, VCL9, and VCL12 are not real words and can be used as a validity check.


A bunch more questions were then asked:


education           "How much education have you completed?", 1=Less than high school, 2=High school, 3=University degree, 4=Graduate degree
urban               "What type of area did you live when you were a child?", 1=Rural (country side), 2=Suburban, 3=Urban (town, city)
gender              "What is your gender?", 1=Male, 2=Female, 3=Other
engnat              "Is English your native language?", 1=Yes, 2=No
age                 "How many years old are you?"
hand                "What hand do you use to write with?", 1=Right, 2=Left, 3=Both
religion            "What is your religion?", 1=Agnostic, 2=Atheist, 3=Buddhist, 4=Christian (Catholic), 5=Christian (Mormon), 6=Christian (Protestant), 7=Christian (Other), 8=Hindu, 9=Jewish, 10=Muslim, 11=Sikh, 12=Other
orientation         "What is your sexual orientation?", 1=Heterosexual, 2=Bisexual, 3=Homosexual, 4=Asexual, 5=Other
race                "What is your race?", 10=Asian, 20=Arab, 30=Black, 40=Indigenous Australian, 50=Native American, 60=White, 70=Other
voted               "Have you voted in a national election in the past year?", 1=Yes, 2=No
married             "What is your marital status?", 1=Never married, 2=Currently married, 3=Previously married
familysize          "Including you, how many children did your mother have?"        
major               "If you attended a university, what was your major (e.g. "psychology", "English", "civil engineering")?"


The following value were calculated by the server:

country     the user's network location

screenw     width of user's device in pixels
screenh     width of user's device in pixels

The time spend on each page was recorded in seconds:

introelapse
testelapse
surveyelapse
Attenzione

Per comodità vi ho preparato un file di dati dove sono dipsonibili solo le effettive risposte al MACH-IV e al TIPI - Un test di personalità composto da 10 item per misurare le dimensioni del BIG-FIVE.

L’ultima variabile del dato è una variabile dicotomica \(\[0,1\]\). Capirete (forse) a cosa serve.

Per svolgere l’esercitazione, trovate qui il file di dati da importare in R:

library(tidyverse)
library(psych)
library(lavaan)
library(semPlot)
library(corrplot)
load("data.RData")
1
Rappresentazioni grafiche e gestione del dato
2
parallel, EFA, alpha di Cronbach
3
CFA
4
Strutture Fattoriali della CFA
5
Rappresentazione grafica matrici di correlazione
6
carica i dati

Per questa esercitazione, facciamo finta di non sapere assolutamente nulla sul MACH, vogliamo validarlo noi e non sappiamo quante dimensioni latenti sono coinvolte.

Volendo valutare anche la validità della misura del MACH, è stata somministrata la scala TIPI (Ten Item Personality Inventory), che misura le 5 dimensioni del Big Five con 10 item (due per dimensione). Lo scoring del TIPI è come segue:

Dimensione Item
Extraversion (E) 1 + 6R
Agreeableness (A) 2R + 7
Conscientiousness (C) 3 + 8R
Emotional Stability (N) 4R + 9
Openness to Experience (O) 5 + 10R

1.1 Cose da fare

MACH
  • Leggere gli item:
    • Numero di dimensioni possibili?
    • Ci sono item reverse? Se si, quali?
  • Se ci sono item reverse (individuati dal testo): capire se sono stati effettivamente girati
  • Descrittive degli item:
    • Skewness e Kurtosis
    • Distribuzione delle varie opzioni di risposta
  • Correlazione
  • Stabilire la dimensionalità
  • Testare la dimensionalità con EFA
  • Confermare il modello trovato da EFA con un approccio confermativo

BONUS:

Correlare il/i punteggi di MACH con i punteggi calcolati dal TIPI

TIPI

Gli item reverse sono già girati giusti.

Va solo verificata la coerenza interna di ogni scala tramite il calcolo dell’\(\alpha\) di Cronbach

Calcolare i punteggi di scala come segue:

\[X_D = \dfrac{i + j}{2}, \qquad i \neq j\] e \(D \in \{E, A, C, N, O\}\)

1.1.1 TIPI

Commenti?

1.1.1.1 Coerenza interna del TIPI e calcolo punteggi

tipi_alpha = NULL
for (i in 1:5) {
  temp = psych::alpha(tipi[, c(i, i +5)])$total
  tipi_alpha = rbind(tipi_alpha, temp)
}
rownames(tipi_alpha) = c("E", "A", "C", "N", "O")

for (i in 1:5) {
  X = rowMeans(tipi[, c(i, i+1)])
  assign(rownames(tipi_alpha)[i], 
         X)
}
# valori di alpha di Cronbach
apply(tipi_alpha, 2, round, digits = 3)
  raw_alpha std.alpha G6(smc) average_r   S/N   ase  mean    sd median_r
E     0.793     0.793   0.657     0.657 3.833 0.006 3.492 1.774    0.657
A     0.497     0.498   0.331     0.331 0.991 0.015 3.945 1.457    0.331
C     0.652     0.657   0.489     0.489 1.914 0.010 4.620 1.567    0.489
N     0.746     0.748   0.598     0.598 2.974 0.008 4.244 1.708    0.598
O     0.130     0.135   0.072     0.072 0.156 0.025 4.495 1.139    0.072
# punteggi TIPI
tipiscore = data.frame(E, A, C, N, O)
head(tipiscore)
    E   A   C   N   O
1 2.5 4.5 6.0 5.0 3.0
2 5.0 6.5 5.5 5.5 4.0
3 3.0 3.5 5.0 6.0 6.0
4 2.0 2.0 2.5 4.5 5.0
5 2.0 2.0 2.0 4.0 3.5
6 4.5 3.0 5.0 7.0 4.0

2 MACH - Analisi

La variabile dicotomica filter serve per fare la cross validation. Va usata fin dalle analisi preliminari di tutti gli item per splittare in due il campione.

  • Analisi preliminare e EFA: filter == 0
  • Analisi confermativa: 1: filter == 1

2.1 Item

machpre = data[data$filter == 0, c(1:20)]
machpre$sbj = 1:nrow(machpre)
machprelong = pivot_longer(machpre, cols=!sbj)
mysum = machprelong %>%  
  group_by(name, value) %>%  
  summarise(prop = n()/nrow(machpre))
ggplot(mysum, 
       aes(x = value, y = prop, fill = factor(value))) + geom_bar(stat="identity") + facet_wrap(~name)

machcor = psych::polychoric(machpre[,-ncol(machpre)])$rho
corrplot(machcor, type="lower", is.corr = T, tl.cex      = 0.85,
         tl.col      = "black",
         title       = "Correlazioni MACH",
         mar         = c(0, 0, 2, 0),
         addgrid.col = "white")
(a) Frequenze nelle categorie di risposta
(b) Matrice di correlazione
Figura 1: Item MACH
Considerazioni

Posso usare altri modi per controllare la presenza di item reverse?

è il metodo più adeguato per valutare se esistono item reverse nella situazione in cui ci troviamo (i.e., non abbiamo idea della struttura fattoriale, siamo nel buio)?

2.1.1 Sliding doors

O si decide di girare gli item e quindi andare avanti con l’ipotesi che sia effettivamente reverse di una stessa dimensione o si prende la decisione più drastica di tenere gli item così come sono e portare avanti entrambe le strade:

  • Gruppo 1: Una dimensione con item reverse
  • Gruppo 2: N dimensioni, lasciamo gli item così come sono A seconda del gruppo a cui avete deciso di appartenere, portate avanti le analisi mancanti :)

Materiale che può servire: