Inference for Two Means: To pool or not to pool? (Old, fast version) @jbstatistics

Inference for Two Means: To pool or not to pool? (Old, fast version) @jbstatistics

Uploaded May 2012 | Updated September 2026, 2 hours ago

I discuss the assumptions of both the pooled-variance and Welch (unpooled variance) t procedures, and their advantages and disadvantages. I illustrate some of pros and cons using the results of two simulations.

Inference for Two Means: To pool or not to pool? (Old, fast version)

One-Way ANOVA: The Formulas

Inference for One Proportion: An Example

The Sampling Distribution of the Sample Proportion

An Introduction to Inference for Two Proportions

Simple Linear Regression: Assumptions

Simple Linear Regression: A Full Example (Old, fast version)

Chi-square Tests for One-way Tables

Finding the Appropriate z Value for the Confidence Interval Formula (Using a Table)

Welch (Unpooled Variance) t Tests and Confidence Intervals: An Example

Inference for Two Proportions: Introduction

An Introduction to the Chi-Square Distribution

Inference for Two Means: To pool or not to pool? (Old, fast version)