Factor analysis Flashcards Preview

Stats > Factor analysis > Flashcards

Flashcards in Factor analysis Deck (13)
Loading flashcards...
1

What is factor analysis used for?

Although factor analysis is typically associated with questionnaire data, it can be used on any data set with lots of variables

2

How do you reduce all of your questions into a smaller number of more meaningful variables?

-Understand distinct aspects of a questionnaire
-Form a smaller dataset that is easier to analyse

3

What are manifest variables?

Your individual questions

4

What are latent variables?

Your broad factors

5

What does Kaiser-Meyer-Olkin (KMO) measure?

•Sampling adequacy
•Are there enough to have a reliable solution?

6

What does a determinant measure?

• Tests for singularity in the data
• Variables should be correlated, but not too much

7

What does Bartlett's test of sphericity measure?

• Correlations between clusters of variables
• FA is only appropriate if variables correlate

8

What is a determinant? (vs sphericity)

-Shouldn’t have all variables correlated.
-If all questions represent the same thing, what is there to factor together?

9

What is sphericity? (vs determinant)

Must be some correlations between variables.
If each question represents a different thing, how can we make factors?

10

In a rotation, where do you want the factors to be positioned?

The two factors are far from each other: clearly distinct factors Likely to be a “good” solution

11

In a rotation, where you you want your items to be located?

Items tightly clustered: Likely to be a “good” factor

12

What is factor loading?

-Tells you how good the item is within the factor
-Correlation between an individual item and factor it is placed in
-High loadings are good
-Greater than .40 - good enough to be included within a factor

13

What is split half reliability? (internal consistency)

- Divide items in half: each half should be highly correlated
(consistency of the measure)
- Cronbach’s alpha (α): all ways of splitting the items in half combined in one measure – mean split half