Lecture 5

Question 1

Exploratory Factor analysis

Answer 1

High correlation between items might suggest that there might be another factor relevant. This might be figured with exploratory analysis.
1-How many factors needed to explain the correlation among items?
2- What do these factors represent

Question 2

How to determine the factors in Exploratory facyor analysis?

Answer 2

1-Screeplot
2-Eigen value >1
3-Inspection of the factor loadings

Question 3

What is Factor rotation?

Answer 3

Transform the factor loadings to improve interpretability of the factors. (Minimize or maximize the factor loadings in a row)

Question 4

Types of rotations?

Answer 4

1-Orthogonal rotation (Varimax)
2-Oblique rotation (Oblivion/Promax)

Question 5

Orthogonal rotation

Answer 5

Assumes correlation between factor 1 and factor 2 is equal to 0

Question 6

Oblique rotation

Answer 6

Correlation between factor 1 and factır 2 is not 0 .
1-Pattern matrix
2-Structure matrix

Question 7

How do we decide which rotation to choose?

Answer 7

It’s subjective. according to interpretability and theory.

Question 8

Communality

Answer 8

How much of the variance in the item is explained by the factors?

• Doesn’t change according to the rotations. remains the same.

Question 9

Total explained variance

Answer 9

How much do the two common factors explain of the total variance of 6 items?

1- The answer depends on the rotation.