This question concerns some concepts about hypothesis testing and confidence interval. For each part below, you must explain your answer.
(a) Suppose we are doing a one-sample t test at the 5% level of significance where the hypotheses are H0 : μ = 0 vs H1 : μ > 0. The number of observations is 8. What is the critical value? [2 marks]
(b) Suppose we are doing a hypothesis test and we can reject H0 at the 1% level of significance, can we reject the same H0 (with the same H1) at the 10% level of significance? [2 marks]
(c) Suppose we are doing a hypothesis test and we cannot reject H0 at the 5% level of significance, can we reject the same H0 (with the same H1) at the 1% level of significance? [2 marks]
(d) Suppose we are doing a two-sample proportion test at the 5% level of significance where the hypotheses are H0 : p1 - p2 = 0 vs H1 : p1 - p2 ā 0. The calculated test statistic is -1.21. Can we reject H0? [2 marks]
(e) Based on the data, we obtain (0.53, 0.87) as the 95% confidence interval for the true mean. Can we reject H0 : μ = 0.5 against H1 : μ ā 0.5 at the 5% level of significance? [2 marks]