Question

Describe how to write the null and alternative hypotheses based on a claim. Provide at least one example to clarify your explanation.

Answer 1

For testing any hypothesis by using statistical inference, we need to write the null and alternative hypotheses for the given test. We write the null and alternative hypotheses based on the claim. Most of the times, the claim is nothing but the alternative hypothesis, but sometimes claim would be null hypothesis. There is no specific rule such that the alternative hypothesis is always the claim. It depends on what the researcher want to prove. Let us see one example. Suppose researcher want to check the claim whether the average weight of the students is more than 50 kg. In this example, the researchers claim would be an alternative hypothesis. The null and alternative hypotheses for this test are given as below:

Null hypothesis: H₀: The average weight of the students is 50 kg.

Alternative hypothesis: H_a: The average weight of the students is more than 50 kg.

In this case, claim is the alternative hypothesis.

If the researcher wants to check whether the average weight of the students is 50 kg., then the null and alternative hypotheses are given as below:

Null hypothesis: H₀: The average weight of the students is 50 kg.

Alternative hypothesis: H_a: The average weight of the students is not 50 kg.

In this case, claim is the null hypothesis.