Alternative Hypothesis
The alternative hypothesis H₁ (or Hₐ) is a statement that contradicts the null hypothesis, typically asserting that an effect or difference exists. It can be two-sided (μ ≠ value) or one-sided (μ > value or μ < value). The direction of H₁ is determined by the research question being investigated.
Real World
A pharmaceutical company testing a new painkiller sets H₁: μ > 0 (the drug reduces pain more than a placebo) based on prior clinical evidence suggesting a positive effect — making it a one-sided test.
Exam Focus
State H₁ using the correct parameter and inequality sign; losing this mark is the most common error in hypothesis testing questions.
How well did you know this?