The t-Test (AQA A-Level Further Maths): Flashcards

Population variance unknown

$n - 1$

$t = \frac{\bar{X} - \mu_0}{S/\sqrt{n}}$

$n - 1$

Makes it an unbiased estimator

Heavier tails than Normal distribution

Large sample size ($n \geq 30$)

Population Normal, sample random

$\bar{X} \pm t \times \frac{s}{\sqrt{n}}$

Both tails of distribution