如何计算Two-Sample t-Test

learn.whatIsHeading

The t-test determines whether the means of two groups are statistically different. The independent (two-sample) t-test compares two separate groups; the paired t-test compares the same subjects under two conditions. Developed by William Gosset ('Student') at Guinness Brewery.

分步指南

1. 1t = (x̄₁ − x̄₂) / √(s₁²/n₁ + s₂²/n₂)
2. 2x̄ = group mean · s² = variance · n = sample size
3. 3df calculated by Welch-Satterthwaite equation
4. 4Compare t-statistic to t-distribution at given df and α

例题解析