Problem 8.C.1f
Lightning Deaths Listed below are the numbers of deaths from lightning strikes in the United States each year for a sequence of recent and consecutive years. Find the values of the indicated statistics.
46 51 44 51 43 32 38 48 45 27 34 29 26 28 23 26 28 40 16 20
f. What important feature of the data is not revealed from an examination of the statistics, and what tool would be helpful in revealing it? What does a quick examination of the data reveal?
Problem 8.c.1c
Lightning Deaths Listed below are the numbers of deaths from lightning strikes in the United States each year for a sequence of recent and consecutive years. Find the values of the indicated statistics.
46 51 44 51 43 32 38 48 45 27 34 29 26 28 23 26 28 40 16 20
c. standard deviation
Problem 8.c.1d
Lightning Deaths Listed below are the numbers of deaths from lightning strikes in the United States each year for a sequence of recent and consecutive years. Find the values of the indicated statistics.
46 51 44 51 43 32 38 48 45 27 34 29 26 28 23 26 28 40 16 20
d. Variance
Problem 8.c.1e
Lightning Deaths Listed below are the numbers of deaths from lightning strikes in the United States each year for a sequence of recent and consecutive years. Find the values of the indicated statistics.
46 51 44 51 43 32 38 48 45 27 34 29 26 28 23 26 28 40 16 20
e. Range
Problem 8.c.8a
Lightning Deaths Based on the results given in Cumulative Review Exercise 6, assume that for a randomly selected lightning death, there is a 0.8 probability that the victim is a male.
a. Find the probability that three random people killed by lightning strikes are all males.
Problem 8.CR.4
Hypothesis Test for Lightning Deaths Refer to the sample data given in Cumulative Review Exercise 1 and consider those data to be a random sample of annual lightning deaths from recent years. Use those data with a 0.01 significance level to test the claim that the mean number of annual lightning deaths is less than the mean of 72.6 deaths from the 1980s. If the mean is now lower than in the past, identify one of the several factors that could explain the decline.
Problem 8.CQQ.1
Discarded Plastic Data Set 42 “Garbage Weight” includes weights (pounds) of discarded plastic from 62 different households. Those 62 weights have a mean of 1.911 pounds and a standard deviation of 1.065 pounds. We want to use a 0.05 level of significance to test the claim that this sample is from a population with a mean less than 2.000 pounds. Identify the null hypothesis and alternative hypothesis.
Problem 8.CQQ.2
Discarded Plastic Find the test statistic used for the hypothesis test described in Exercise 1.
Problem 8.CQQ.3
Discarded Plastic
What distribution is used for the hypothesis test described in Exercise 1?
For the hypothesis test described in Exercise 1, is it necessary to determine whether the 62 weights appear to be from a population having a normal distribution? Why or why not?
Problem 8.CQQ.4
Discarded Plastic The P-value for the hypothesis test described in Exercise 1 is 0.2565.
What should be concluded about the null hypothesis?
What is the final conclusion that addresses the original claim?
Problem 8.CQQ.10
Robust Explain what is meant by the statements that the t test for a claim about μ is robust, but the (chi)^2 test for a claim about σ is not robust.
Problem 8.CR.6
Lightning Deaths The graph in Cumulative Review Exercise 5 was created by using data consisting of 242 male deaths from lightning strikes and 64 female deaths from lightning strikes. Assume that these data are randomly selected lightning deaths and proceed to test the claim that the proportion of male deaths is greater than . Use a 0.01 significance level. Any explanation for the result?
Problem 8.RE.1
Job Search A Gallup poll of 195,600 employees showed that 51% of them were actively searching for new jobs. Use a 0.01 significance level to test the claim that the majority of employees are searching for new jobs
Problem 8.RE.5a
Type I Error and Type II Error
a. In general, what is a type I error? In general, what is a type II error?
Problem 8.RE.4
Perception and Reality In a presidential election, 308 out of 611 voters surveyed said that they voted for the candidate who won (based on data from ICR Survey Research Group). Use a 0.05 significance level to test the claim that among all voters, the percentage who believe that they voted for the winning candidate is equal to 43%, which is the actual percentage of votes for the winning candidate. What does the result suggest about voter perceptions?
Ch. 8 - Hypothesis Testing
