MA145 Final Exam - Takehome Portion
For each of the problems below, use the MA145 technology guide to perform a statistical analysis.
You should justify your choice of method, including any assumptions made in the use of the method.
You should indicate whether a two-tailed, left-tailed, or right-tailed analysis is appropriate,
and, in hypothesis testing problems, state the null and alternative hypotheses.
If the problem does not specify a level of significance, you should choose one.
Problem 1
Archeological evidence in the form of shell casings is recovered from the site of a late nineteenth century battle fought by Native Americans and federal troops. Ballistics analysis indicates that of 85 individual firearms believed to be used by the Native Americans, 50% were repeating rifles. If we consider these 85 weapons to be a simple random sample of the Native American firearms, construct a 95% confidence interval for the proportion of Native American firearms that were repeating rifles at the time of the battle.
Problem 2
One set of figures claims that 250,122 of 2,750,000 troops who fought for the Union died of disease. A sample of the records of 23 Confederate units revealed that 245 of 1,810 soldiers were reported to have died of disease. Does this sample support the claim that Confederate units had the same proportion of deaths from disease as that reported by the Union statistics?
Problem 3
During the tenure of a certain majority leader, members of Congress affiliated with the majority
party voted in accordance with the wishes of the majority leader 85% of the time. On the first
32 votes following the appointment of a new majority leader, conformance with the party line
was 68 percent. Considered as a random sample, do the first 32 votes suggest that the level
of conformance has changed?