Question

What is one example where a hypothesis test would be an appropriate way to make a decision in your professional or interest area? Why would this method be better than another (for example, confidence intervals, point estimates or probability). What would an appropriate null and alternate hypothesis be?

*please write clearly. thank yoy

Answer 1

Hypothesis tests and confidence intervals are inferential methods that rely on an approximated sampling distribution. Confidence intervals estimate a population parameter using sample data. Hypothesis tests use data from a sample to test a specified hypothesis. Hypothesis testing requires that we have a hypothesized parameter. Point Estimation deals with the method of estimating an unknown parameter of a population-based on Random Samples from the same population. That is point estimate gives a single value for the parameter.

Therefore we use hypothesis testing when we want to do a strict comparison with a pre-specified hypothesis and significance level.

Consider the following example.

An engineer measured the hardness of 20 pieces of iron. The engineer hypothesized that the mean hardness of all such iron pieces is greater than 170. Therefore, he was interested in testing the hypotheses

H₀ : μ = 170
H₁ : μ > 170

Consider the following example.

An engineer measured the hardness of 20 pieces of iron. The engineer hypothesized that the mean hardness of all such iron pieces is greater than 170. Therefore, he was interested in testing the hypotheses

H₀ : μ = 170
H₁ : μ > 170

Consider the following example.

An engineer measured the hardness of 20 pieces of iron. The engineer hypothesized that the mean hardness of all such iron pieces is greater than 170. Therefore, he was interested in testing the hypotheses

H₀ : μ = 170
H₁ : μ > 170

The null hypothesis is the hypothesis that the researcher is trying to disprove. Here H₀ is the null hypothesis and H₁ is the alternative hypothesis. The alternative hypothesis is the inverse of the null hypothesis.