Attachments: RES 342 Week 2 Individual Quiz (UOP Course).docx [ Preview Here ]
Prepare to take a quiz on topics covered in previous weeks.
RES/342 Week One: One Sample Hypothesis Testing
Objective: Identify the formal hypothesis testing process.
1. Hypothesis testing is the statistical process of analyzing sample data by using probability theory to determine whether a stated hypothesis is reasonable. For a particular test, a business owner wanted to know whether changes in a production practice resulted in significant timesaving in manufacturing the company’s product. The business owner develops the alternative hypothesis that the population mean after the change is less than the population mean before the change. To test this question,
a. 0 a two-tailed test should be applied
b. 0 a left-tailed test should be applied is the correct answer
c. 0 a right-tailed test should be applied
d. 0 more information is required to make a decision
Objective: Perform a hypothesis test of one proportion.
2. The Roman Senate has become concerned about the loyalty of the army in Gaul commanded by Julius Caesar. They claim that, of the 80,000 men in the army, at least 28,000 are foreign barbarians. Caesar believes that there are fewer barbarians, so the Senate should not worry. He polls a legion of 1,000 men and finds that 340 of them are barbarians. Assume the value of the test statistic is -0.70. Calculate the p-value for this test using Microsoft® Excel®.
a. 0 =NORMSDIST(-0.7) yes
b. 0 =TDIST(-0.70,999,1)
c. 0 =2*(NORMSDIST(-0.7))
d. 0 =TDIST(0.7,999,2)
Objective: Perform a hypothesis test of one population mean using the standard normal distribution.
3. The manager of a fast food restaurant is concerned that it is taking too much time for drive-thru customers to be processed. The time period of concern is from when a customer’s order is placed to when he or she receives his or her food. An acceptable amount of time for this process has been 1.3 minutes. To address this concern, a sample test was conducted. A sample of 24 random customers was taken and it was determined that the processing time was 1.41 minutes, with a standard deviation of 0.12 minutes. Is this difference significant? At the 0.05 significance level, which of these statements is correct?
a. 0 The critical value is ±1.96.
b. 0 The critical value is 1.714. yes
c. 0 The test statistic is 0.92.
d. 0 The test statistic is 4.58.
Objective: Interpret the results of hypothesis tests.
4. The mean length of a small counterbalance bar is 43 millimeters. There is concern that the adjustments of the machine producing the bars have changed. Test the claim, at the 0.02 level, that there has been no change in the mean length. The alternate hypothesis is that there has been a change. Twelve bars (n = 12) were selected at random and their lengths were recorded. The lengths are, in millimeters, 42, 39, 42, 45, 43, 40, 39, 41, 40, 42, 43, and 42. The mean of the sample is 41.5 and the standard deviation is 1.784. Computed, t equals – 2.913. Has there been a statistically significant change in the mean length of the bars?
a. 0 A larger test sample is needed.
b. 0 Yes, because the computed t lies in the area beyond the critical value correct
c. 0 No, because the information given is not complete
d. 0 No, because the computed t lies in the area to the right of –2.718