Itranscript Call centers typically have high turnover. The director of human resources for a large bank has compiled data o about 70 former employees at one of the bank's call centers. The accompanying table shows this data. In writin article about call center working conditions, a reporter has claimed that the average tenure is no more than two Formulate and test a hypothesis using these data to determine if this claim can be disputed. Use a level of significance of 0.05. Click the icon to view the call center data. KIER Is there sufficient evidence at the 0.05 level of significance that the average tenure is no more than two years? Determine the null hypothesis, Ho, and the alternative hypothesis, H₁. Ho H

You can assess normality of data using

In a 2015 study entitled How Undergraduate Students Use Credit Cards, it was reported that undergraduate students have a mean credit card balance higher than $3000. This figure was an all-time high and had increased 42% over the previous five years. Assume that a current study is being conducted to determine if it can be concluded that the mean credit card balance for undergraduate students has continued to increase compared to the report. They want to test to see if the balance for students in 2019 is higher than the balance for students in 2015. See the sample below of undergraduate students in 2015 and different undergraduate students in 2019.    Credit Card Increase Students in 2015 Students in 2019 2500 3300 2200 5450 1500 8000 930 2000 5300 870 1150 250 2700 3000 3300 2200 What can we conclude from this t-test?        a) Reject the null hypotesis OR Fail to reject the null hypotesis? b) We can conclude that the student balance in 2019 are significatly…

Please answer the question in the photo

A hospital in New York commonly conducts stress tests to study the heart muscle after a person has a heart attack. Members of the diagnostic imaging department conducted a quality improvement project with the objective of reducing the turnaround time for stress tests. Turnaround time is defined as the time from when a test is ordered to when the radiologist signs off on the test results. Initially, the mean turnaround time for a stress test was 68 hours. After incorporating changes into the stress-test process, the quality improvement team collected a sample of 50 turnaround times. In this sample, the mean turnaround time was 32 hours, with a sample standard deviation of 9 hours.   (a) Using the critical value approach, if you test the null hypothesis at the 0.01 level of significance, is there evidence that the new process has reduced turnaround time?  (Be sure to list the null and alternate hypotheses, the value of the test statistic, the decision rule (using the critical value(s)…

The IQ scores for a random sample of subjects with medium lead levels in their blood and another random sample of subjects with high lead levels in their blood are given below. Use a 0.05 significance level to test the claim that subjects with medium lead levels have full IQ scores with a higher median that the median full IQ score for subjects with high lead levels. Does lead level appear to affect full IQ scores? Click the icon to view the data table. First define the null and alternative hypotheses. Ho: H₁: Data Table Let the medium lead level be sample 1. Medium Lead High Lead Level Level 66 98 64 87 63 HR22CTCTETUE 2 13 100 83 84 84 70 73 70 78 91 61 72 88 73 76 63 66 61 64 61 66 92 76 107 66 X

A consumer advocacy group conducts a large study on car rental practices. Among other things, the group would like to do a statistical test on the mean monthly mileage,μ, of cars rented in the US this year. The consumer advocacy group has good reason to believe that the average monthly mileage for rental cars in the US this year is higher than last year's average, which was2700miles. The group plans to perform a statistical test on the value ofu. To do this, choose a random sample of miles driven per month and calculate that the sample mean is2835miles and the standard deviation is750miles. Use this information to complete the parts below. (to) What are the null hypothesesh and the alternative hypothesish, What should be used to perform the test? h :0 0 (b) (c) h :0 1 Assume that the group decides not to reject the null hypothesis. What kind of mistake could you be making? (Choose an option) Suppose the true average monthly mileage for rental cars in the US this year is2850. Fill in…

The Energy Star rating system is an energy efficiency program run by the U.S. Environmental Protection Agency (EPA)Energy Star certified appliances, such as televisions and refrigerators, are rated in regard to their average energy consumption per year. A certain brand of Energy Star certified refrigerator is stated to have a mean yearly electricity cost of $99. A consumer advocacy organization believes that this claim is wrong, that the energy consumption of this particular refrigerator is different than $99 per year. The group collected a random sample of 16 refrigerators of the model in question and had each lab-tested for electricity consumption. The yearly energy consumption of each is given below. 96.7697.898.67 95.52 97.8 95.896.9299.57 97.64 95.46 98.03 96.42 99.32 98.99 95.2197.12 Using alpha = 0.1 , test the hypothesis that the average yearly electricity consumption of the refrigerator in question is different than $99 per year. Assume that the distribution of all electricity…