individual differences

Question 1

what is the individual differences approach

Answer 1

aim to understand what makes people different, in what ways do they differ and in what ways are they similar

through looking at behaviour, motivation and thought

should be able to predict future behaviour and explain why

Question 2

what is a latent factor

Answer 2

unobservable but we see what they result in

Question 3

what real life implications are there

Answer 3

finding a partner, friends, employee
who to follow, what to beleive in , who to vote for
inequality in education, wealth, success and power
health and happiness
intervention interacations
need to avoid a eugenics-like narrative of elitism

Question 4

what do we measure

Answer 4

domains of functioning: personality, intelligence, risk preference, social ability, morality
principled way to derive these domains: predictors of covaraince

Question 5

what is factor analysis

Answer 5

Factor Analysis (FA) refers to a family of statistical techniques which examine the relationship between a set of variables in order to identify groups of variables that are highly correlated. 
These groups of variables, which correlate more with each other than with other groups of variables form a ‘factor’. In an ideal world, they would correlate only with one another and not with any of the other variables in the study. 
A central aim of factor analysis is the orderly simplification of a number of interrelated measures, with minimum loss of information.

Question 6

what are the two types of factor analysis

Answer 6

Exploratory FA describes a set of correlations among variables (correlation matrix)
Uses a smaller number of common factors
Minimum cross loadings (preferably 0)
Confirmatory FA tests the goodness of fit of a dataset
Using a pre-specified model of factors
With success being non-significant goodness of fit test

Question 7

what are the advantages of factor analysis

Answer 7

Theory development: key to the formulation of the most widely used theories of personality and intelligence
Theory evaluation: difficult to evaluate the theories without a reasonable understanding of FA
Data simplification

Question 8

what are the uses of exploratory factor analysis

Answer 8

to identify the number and nature of factors required to account for the intercorrelations between items

Question 9

what are the uses of confirmatory factor analysis

Answer 9

to test the applicability of a theory of intelligence or personality to a new group - culture, gender, political grouping

assess reliability and historic trends

Question 10

what are the stages of factor analysis

Answer 10

measure variables
calculate correlations matrix
factor extraction: principal component analysis
rotation method: Varimax
number of factors 
interpret factors: loadings
name factors
at every stage there is a high degree of subjectivity 

Most intercorrelation matrices are not simple - there are more items, more complex patterns of interaction
Allows us to specify numerically the contribution each factor makes to each variable in the intercorrelation matrix
Numerical contributors are loadings and can be thought of as correlations between the variables and the factor
Important when designing tests, representativeness of an item.

Question 11

what is H^2

Answer 11

communality for each variables
sum of squares of the factor loadings for each variable
values between 1-0
if 0 variables share nothing in common
Varimax rotation attempts to maximise and minimise loadings on each factor so that the loadings approach 1 or 0
Communalities are the same after the varimax rotation, but the amount of variance extracted from the intercorrelation matrix by each factor has changed