Pooled Variance Calculator
The pooled variance calculator is a useful tool for calculating the combined variance of two or more sample datasets. This measure is often used in statistics to assess variability across multiple samples, especially when the sample sizes are different. By calculating pooled variance, researchers can make accurate comparisons between groups.
What is Pooled Variance?
Pooled variance is a weighted average of variances from two or more samples. It accounts for the sample size and variability within each sample, providing a single estimate of variance for a combined dataset. This is particularly useful in t-tests and ANOVA where variances need to be consistent across groups.
How to Calculate Pooled Variance
The formula for pooled variance (when combining two samples) is:
S²p = [(n₁ - 1)S₁² + (n₂ - 1)S₂²] / (n₁ + n₂ - 2)
Where:
- S²p is the pooled variance.
- S₁² and S₂² are the variances of sample 1 and sample 2, respectively.
- n₁ and n₂ are the sample sizes of sample 1 and sample 2.
Calculate Pooled Variance
Benefits of Using the Pooled Variance Calculator
- Accuracy: Get accurate results in a fraction of the time it takes to calculate manually.
- Convenience: No need for complex equations; simply input your sample data.
- Versatile: Useful for various statistical tests, including t-tests and ANOVA.