In a market research study involving 11 people, 7 preferred Product X, 3 preferred
Product Y, and 1 expressed no preference. A sign test is selected using the 0.05 level of
significance. What is the alternate hypothesis?
When dependent samples are used to test for differences in the means, we compute
________________ differences.
The t distribution approaches the ____________ distribution as the sample size
increases.
The waiting time for patients at a local walk-in health clinic follows a normal
distribution with a mean of 15 minutes and a population standard deviation of 5
minutes. The quality-assurance department sampled 50 patients and found that the mean
waiting time was 14.25 minutes. At the 0.025 significance level, decide if the sample
data support the claim that the mean waiting time is less than 15 minutes. State your
decision in terms of the null hypothesis.
A manufacturer wants to increase the shelf life of a line of cake mixes. Past records
indicate that the average shelf life of the mix is 216 days. After a revised mix has been
developed, a sample of nine boxes of cake mix had a mean of 217.222 days and a
standard deviation of 1.2019 days. At the 0.025 significance level, decide if the sample
data support the claim that shelf life has increased. State your decision in terms of the
null hypothesis.
What are the two population parameters that specify the location and dispersion for a
normal distribution?