Assignment:
Q1 What is the difference between a null hypothesis and an alternative hypothesis? Is the null hypothesis always the same as the verbal claim or assertion that led to the test? Why or why not?
Q2 For each of the following pairs of null and alternative hypotheses, determine whether the pair would be appropriate for a hypothesis test. If a pair is deemed inappropriate, explain why.
a. H0: u > or = 10, H1: u < 10
b. H0: u = 30, H1: u not equal to 30
c. H0: u > 90, H1: u < or = 90
d. H0: u < or = 75, H1: u < or = 85
e. H0: x > or = 15, H1: x < 15
f. H0: x = 58, H1: x not equal to 58
Q3 For each of the following pairs of null and alternative hypotheses, determine whether the pair would be appropriate for a hypothesis test. If a pair is deemed inappropriate, explain why.
a. H0: pie > or = 0.30, H1: pie < 0.35
b. H0: pie = 0.72, H1: pie is not equal to 0.72
c. H0: Pie < or = 0.25, H1: pie > 0.25
d. H0: pie > or = 0.48, H1: pie > 0.48
e. H0: pie < or = 0.70, H1: pie > 0.70
f. H0: p > or = 0.65, H1: p < 0.65
Q4 On CNN and other news networks, guests often express their opinions in rather strong, persuasive, and sometimes frightening terms. For example, a scientist who strongly believes that global warming is taking place will warn us of the dire consequences (such as rising sea levels, coastal flooding, and global climate change) she foresees if we do not take her arguments seriously. If the scientist is correct, and the world does not take her seriously, would this be a Type I error or a Type II error? Briefly explain your reasoning.
Q5 Many law enforcement agencies use voice-stress analysis to help determine whether persons under interrogation are lying. If the sound frequency of a person's voice changes when asked a question, the presumption is that the person is being untruthful. For this situation, state the null and alternative hypotheses in verbal terms, then identify what would constitute a Type I error and a Type II error in this situation.