Partial Eta Squared Calculator

Partial Eta Squared Formula:

\[ \eta_p^2 = \frac{SS_{\text{effect}}}{SS_{\text{effect}} + SS_{\text{error}}} \]

Partial Eta Squared (η_p²):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is Partial Eta Squared?

Partial eta squared (η_p²) is an effect size measure used in ANOVA that represents the proportion of variance in the dependent variable that is attributable to a particular independent variable, while controlling for other variables in the model.

2. How Does the Calculator Work?

The calculator uses the partial eta squared formula:

\[ \eta_p^2 = \frac{SS_{\text{effect}}}{SS_{\text{effect}} + SS_{\text{error}}} \]

Where:

\( SS_{\text{effect}} \) — Sum of squares for the effect (independent variable)
\( SS_{\text{error}} \) — Sum of squares for the error term

Explanation: Partial eta squared quantifies the effect size by measuring the proportion of total variance explained by a specific factor, accounting for other variables in the analysis.

3. Importance of Partial Eta Squared

Details: Effect size measures like partial eta squared are crucial for understanding the practical significance of research findings beyond statistical significance. They help researchers determine the magnitude of effects and facilitate comparisons across studies.

4. Using the Calculator

Tips: Enter the sum of squares for the effect and the sum of squares for the error term. Both values must be positive numbers, with SS_error greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is a good partial eta squared value?
A: Generally, values of 0.01 indicate a small effect, 0.06 a medium effect, and 0.14 a large effect, though interpretation depends on the research context.

Q2: How does partial eta squared differ from eta squared?
A: Partial eta squared controls for other variables in the model, while eta squared does not. Partial eta squared is generally preferred in multifactor ANOVA designs.

Q3: When should I use partial eta squared?
A: Use partial eta squared in ANOVA analyses to measure effect size for individual factors while accounting for the presence of other variables in the model.

Q4: Are there limitations to partial eta squared?
A: Partial eta squared can be biased in small samples and may overestimate effect sizes. It's also not comparable across studies with different designs.

Q5: Can partial eta squared be negative?
A: No, partial eta squared values range from 0 to 1, where 0 indicates no effect and values closer to 1 indicate larger effects.