The CSUSM Car Wash Company has recently implemented a new technology package in order to decrease...

  

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The CSUSM Car Wash Company has recently implemented a new technology package in order to decrease customers' total waiting time in the system, which is ultimately expected to increase the satisfaction rate of the customers. Even though most employees believe this is a great move, no study has been conducted yet to measure the actual effectiveness of the new system. As a new employee of the company, you have been asked to help analyze the performance of the new system. As the first step, you have selected an anonymous sample of 400 customers who have experienced both the previous and the new system, and collected their waiting time, satisfaction score, and the number of times they came for car wash services in one year (arrival rate) under both settings (refer to Car Wash data file). 1. Develop 95% confidence intervals for the following parameters before and after the new system was implemented: • Average waiting time, • Mean number of arrivals for service, • Proportion of customers with satisfaction score of 4 and above, 2. Develop null and alternative hypotheses for the following three tentative conjectures: • Mean satisfaction score is greater than or equal to 4 in the new system, • At least 45% of the member customers are from Region 2, Then, conduct hypothesis tests at the 0.05 level of significance to determine if we can reject the above statements. 3. Implementing the new system required a great deal of money from the company. Major shareholders have asked the company to justify this cost. Would you be able to help the company present the benefits of the new system? [Hint: you should test for favorable changes in mean satisfaction score, mean waiting time, and mean number of arrivals]. 4. Test to see if members from different regions have equal mean number of arrivals (requires ANOVA). The CSUSM Car Wash Company has recently implemented a new technology package in order to decrease customers' total waiting time in the system, which is ultimately expected to increase the satisfaction rate of the customers. Even though most employees believe this is a great move, no study has been conducted yet to measure the actual effectiveness of the new system. As a new employee of the company, you have been asked to help analyze the performance of the new system. As the first step, you have selected an anonymous sample of 400 customers who have experienced both the previous and the new system, and collected their waiting time, satisfaction score, and the number of times they came for car wash services in one year (arrival rate) under both settings (refer to Car Wash data file). 1. Develop 95% confidence intervals for the following parameters before and after the new system was implemented: • Average waiting time, • Mean number of arrivals for service, • Proportion of customers with satisfaction score of 4 and above, 2. Develop null and alternative hypotheses for the following three tentative conjectures: • Mean satisfaction score is greater than or equal to 4 in the new system, • At least 45% of the member customers are from Region 2, Then, conduct hypothesis tests at the 0.05 level of significance to determine if we can reject the above statements. 3. Implementing the new system required a great deal of money from the company. Major shareholders have asked the company to justify this cost. Would you be able to help the company present the benefits of the new system? [Hint: you should test for favorable changes in mean satisfaction score, mean waiting time, and mean number of arrivals]. 4. Test to see if members from different regions have equal mean number of arrivals (requires ANOVA).

Answer rating: 100% (QA)

1 Before new system Average waiting time We are given that the sample size is 400 so we can use the tdistribution to find the confidence interval The 95 confidence interval for the average waiting tim... View the full answer