Null and Alternative Hypothesis Practice

The null hypothesis (H₀) is a statement that there is no effect or no difference, and it serves as the default or starting assumption in hypothesis testing.

The alternative hypothesis (Hₐ) is a statement that indicates the presence of an effect or a difference, and it is what the researcher aims to support.

The null hypothesis is denoted by H₀.

The alternative hypothesis is denoted by H₁.

If H₀ is rejected, it suggests that there is sufficient evidence to support the alternative hypothesis (Hₐ).

If H₀ is not rejected, it indicates that there is not enough evidence to support the alternative hypothesis (Hₐ).

A one-tailed test is a hypothesis test that evaluates the direction of the effect, either greater than or less than a certain value.

A two-tailed test is a hypothesis test that evaluates whether there is a difference in either direction (greater than or less than a certain value).

The significance level (α) is the probability of rejecting the null hypothesis when it is actually true, commonly set at 0.05.

A Type I error occurs when the null hypothesis is rejected when it is actually true.