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

Uploaded June 2013 | Updated September 2026, 2 hours ago

I work through an example of a Welch (unpooled variance) t test and confidence interval (in the setting of inference for two means).

The antivenom/swelling data is found in:

Offerman et al. (2009). Subcutaneous crotaline Fab antivenom for the treatment of rattlesnake envenomation in a porcine model. Clinical Toxicology, 47: 61-68.

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

Inference for Two Proportions: Introduction

An Introduction to the Chi-Square Distribution

Simple Linear Regression: Checking Assumptions with Residual Plots

An Introduction to the Normal Distribution

Introduction to the Continuous Uniform Distribution

An Introduction to the Poisson Distribution

Basic Probability: The Multiplication Rule

The Relationship Between Confidence Intervals and Hypothesis Tests

An Introduction to Inference for the Ratio of Two Variances