In: Statistics and Probability
1. According to a recent report, 38% of adults wait until they
are 30 years of age or older to get married for the first time. A
researcher believes this claimed value is too low. He gathers data
in order to test the hypotheses Ho: p = 0.38 vs. Ha: p > 0.38.
In these hypotheses, what does p represent?
A. The sample proportion
B. The population proportion
C. The p-value
D. The sample mean
E. The population mean
2. A claim is made that college students get an average of 6.2
hours of sleep per weeknight. You believe college students get less
than 6.2 hours of sleep per night. You decide to conduct a
hypothesis test by surveying a random sample of 65 college
students. You find your sample gets an average of 5.8 hours of
sleep per night, with a sample standard deviation of 1.2 hours.
What will the test statistic be? Choose the answer below that is
closest to what you calculate, and try not to do a lot of rounding
until you get to the very end of your calculations.
A. -0.1
B. -0.3
C. -0.6
D. -1.2
E. -2.7
3. A hypothesis test is conducted and the p-value is 0.002. What
will the conclusions be at alpha (or significance) levels of 0.10,
0.05, and 0.01?
A. We will reject Ho if the alpha level is 0.01, but not if the
alpha level is 0.05 or 0.10.
B. We will reject Ho if the alpha level is 0.05, but not if the alpha level is 0.10 or 0.01.
C. We will reject Ho if the alpha level is either 0.10 or 0.05, but not if the alpha level is 0.01.
D. We will reject Ho if the alpha level is 0.10, 0.05, or 0.01.
E. We will fail to reject Ho if the alpha level is 0.10, 0.05,
or 0.01.
4. A claim is made that 19% of adults are country music fans. You
believe this claim is incorrect. You would like to test the null
hypothesis that ? = 0.19 versus the alternative hypothesis that ? ≠
0.19. You gather data from a survey of a random sample of 100
adults and obtain a test statistic of 2.4. If we assume the
significance (or alpha) level is α = 0.01, what should your
decision be?
A. Reject the alternative hypothesis
B. Fail to reject the alternative hypothesis
C. Reject the null hypothesis
D. Fail to reject the null hypothesis
E. We cannot reach a conclusion without knowing the sample
proportion.
5. Imagine you have data in the form of proportions and you conduct
a hypothesis test. Assuming you have made no errors in your
calculations, what would it mean if the test statistic ends up
being larger than (or greater than) zero?
A. The sample proportion is equal to the claimed population
proportion.
B. The sample proportion is larger than (or greater than) the claimed population proportion.
C. The sample proportion is smaller than (or less than) the claimed population proportion.
D. The sample size must be very large.
E. The sample size must be very small.