Factor Analysis

Question 1

Operates on item correlation matrix
Asks how many dimensions underpin a questionnaire or rating scale.
Reduces large number of correlations to small number of factors
Correlation reflects relationship between 2 variables
Ranges from -1 to +1

Answer 1

Factor Analysis

Question 2

Visual Perception, Cubes, Lozenges, Paragraph Comprehension, Sentence
Completion, Word Meaning, Addition, Count-the-Dots, Straight-curved Caps

Answer 2

Holzinger & Swineford (1939)

Question 3

Principal Components Analysis (PCA)

Answer 3

Descriptive

- Explore the underlying structure of constructs (components)

Question 4

Steps to FA

Answer 4

• Step 1: Selecting and measuring a set of variables in a given domain
• Step 2: Data screening in order to prepare the correlation matrix
• Step 3: Factor extraction
• Step 4: Factor rotation to increase interpretability
• Step 5: Interpretation
• Further Steps: Validation and reliability of the measures

Question 5

Suitability of questions / items

Answer 5

•A communality of a variable that is 0.75 is very good, but also it should load to an
interpretable factor.

•Variables with communalities below 0.50 are usually dropped (or extract more factors)