Stata Factor Analysis Calculate Percent Variance
Introduction & Importance
Stata factor analysis is a statistical method used to explain the correlations between multiple variables with a smaller set of unobserved latent factors. Calculating the percent variance explained by these factors is crucial for understanding the model’s fit and the importance of the factors.
How to Use This Calculator
- Enter the number of factors (n).
- Enter the eigenvalues, separated by commas.
- Click ‘Calculate’.
Formula & Methodology
The percent variance explained by each factor is calculated as:
Percent Variance = (Eigenvalue / Sum of Eigenvalues) * 100
The total variance explained by all factors is the sum of the percent variances.
Real-World Examples
Data & Statistics
| Factor | Eigenvalue |
|---|---|
| 1 | 3.5 |
| 2 | 1.8 |
| 3 | 1.2 |
| Factor | Percent Variance |
|---|---|
| 1 | 43.75% |
| 2 | 22.5% |
| 3 | 15% |
Expert Tips
- Consider using the scree plot to determine the optimal number of factors.
- Interpret the factor loadings to understand the meaning of each factor.
Interactive FAQ
What are eigenvalues?
Eigenvalues are the solutions to the equation |λI – Σ| = 0, where λ is the eigenvalue, I is the identity matrix, and Σ is the covariance matrix.
For more information, see the Stata Factor Analysis documentation.