Enter Factor Loadings
Example Data Table
| Variable | Factor 1 | Factor 2 | Factor 3 | Communal Variance |
|---|---|---|---|---|
| Service Quality | 0.72 | 0.64 | 0.58 | 1.2644 |
| Trust Score | 0.61 | 0.55 | 0.49 | 0.9147 |
| Engagement | 0.80 | 0.44 | 0.35 | 0.9561 |
Formula Used
Communal variance is the sum of squared factor loadings for one variable.
h² = λ₁² + λ₂² + λ₃² + ... + λₙ²
Here, h² is communal variance. Each λ is a factor loading. A larger value means more variance is shared with the extracted factors.
How to Use This Calculator
Enter the variable name first. Then enter all factor loadings in the loading box. You can separate values with commas, spaces, or new lines. Leave uniqueness blank when you want the tool to estimate it automatically. Press the calculate button. The result appears above the form and below the header.
Understanding Communal Variance
What It Means
Communal variance shows how much of a variable is explained by common factors. It is often used in factor analysis. It helps researchers see whether a variable fits well inside a factor model. A high value suggests strong shared structure. A low value suggests weak connection with the selected factors.
Why It Matters
This measure is useful before making conclusions from survey, psychology, business, education, and social science data. It shows whether an item contributes useful information. If communal variance is very low, the item may not belong in the model. It may need review, removal, or better measurement design.
How Results Are Read
The calculator squares each loading. It then adds all squared values. This creates the communal variance score. When uniqueness is included, the tool also compares shared variance with unexplained variance. The percentage result helps you see the explained share in a simple format.
Good Practice
Always check loadings before using the result. Very small loadings add little value. Very large values can indicate strong factor influence. Use clean data and consistent factors. Compare results across variables. Do not judge the model from one value alone. Review theory, sample size, and factor meaning together.
Reporting Tip
In reports, mention the loadings, squared loading sum, and interpretation. A short explanation makes the result clear. You can export the table as CSV. You can also save a PDF summary for records, audits, or research notes.
FAQs
1. What is communal variance?
Communal variance is the part of a variable explained by shared factors. It is found by adding squared factor loadings.
2. What is a factor loading?
A factor loading shows the relationship between a variable and a factor. Stronger loadings usually explain more shared variance.
3. Can communal variance be above one?
It can happen when using some loading sets or component methods. In many common factor models, values are often interpreted carefully near one.
4. What does low communal variance mean?
Low communal variance means the selected factors explain little of that variable. The item may not fit the model well.
5. Should I enter uniqueness?
You can enter it when known. If left blank, the calculator estimates uniqueness as one minus communal variance.
6. Can I paste many loadings?
Yes. You can paste values separated by commas, spaces, or new lines. The tool reads valid numeric values only.
7. Is this useful for surveys?
Yes. It helps review survey items in factor analysis. It shows how well each item is explained.
8. Does this replace statistical software?
No. It supports quick checks and reporting. Full factor analysis still needs proper statistical software and careful interpretation.