Concept explainers
One of the major measures of the quality of service provided by any organization is the speed with which the organization responds to customer complaints. A large family-held department store selling furniture and flooring, including carpet, had undergone a major expansion in the past several years. In particular, the flooring department had expanded from 2 installation crews to an installation supervisor, a measurer, and 15 installation crews. The store had the business objective of improving its response to complaints. The variable of interest was defined as the number of days between when the complaint was made and when it was resolved. Data were collected from 50 complaints that were made in the past year. The data, stored in Furniture, are as follows:
a. Construct a 95% confidence
b. What assumption must you make about the population distribution in order to construct the confidence interval estimate in (a)?
c. Do you think that the assumption needed in order to construct the confidence interval estimate in (a) is valid? Explain.
d. What effect might your conclusion in (c) have on the validity of the results in (a)?
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Basic Business Statistics
- One of the major measures of the quality of service provided by an organization is the speed with which the organization responds to customer complaints. A large family-held department store selling furniture and flooring, including carpet, had undergone a major expansion in the past several years. In particular, the flooring department had expanded from 2 installation crews to an installation supervisor, a measurer, and 15 installation crews. A business objective of the company was to reduce the time between when the complaint is received and when it is resolved. During a recent year, the company received 50 complaints concerning carpet installation. The data from the 50 complaints, represent the number of days between the receipt of the complaint and the resolution of the complaint: 54 5 35 137 31 27 152 2 123 81 74 27 11 19 126 110 110 29 61 35 94 31 26 5 12 4 165 32 29 28 29 26 25 1 14 13 13 10 5 27 4 52 30 22 36 26 20 23 33 68 Construct a frequency distribution and a percentage…arrow_forwardOne of the major measures of the quality of service provided by an organization is the speed with which the organization responds to customer complaints. A large family-held department store selling furniture and flooring, including carpet, had undergone a major expansion in the past several years. In particular, the flooring department had expanded from 2 installation crews to an installation supervisor, a measurer, and 15 installation crews. A business objective of the company was to reduce the time between when the complaint is received and when it is resolved. During a recent year, the company received 50 complaints concerning carpet installation. The data from the 50 complaints, represent the number of days between the receipt of the complaint and the resolution of the complaint: 54 5 35 137 31 27 152 2 123 81 74 27 11 19 126 110 110 29 61 35 94 31 26 5 12 4 165 32 29 28 29 26 25 1 14 13 13 10 5 27 4 52 30 22 36 26 20 23 33 68 Construct a histogram and a percentage polygon.arrow_forwardOne of the major measures of the quality of service provided by an organization is the speed with which the organization responds to customer complaints. A large family-held department store selling furniture and flooring, including carpet, had undergone a major expansion in the past several years. In particular, the flooring department had expanded from 2 installation crews to an installation supervisor, a measurer, and 15 installation crews. A business objective of the company was to reduce the time between when the complaint is received and when it is resolved. During a recent year, the company received 50 complaints concerning carpet installation. The data from the 50 complaints, represent the number of days between the receipt of the complaint and the resolution of the complaint: 54 5 35 137 31 27 152 2 123 81 74 27 11 19 126 110 110 29 61 35 94 31 26 5 12 4 165 32 29 28 29 26 25 1 14 13 13 10 5 27 4 52 30 22 36 26 20 23 33 68 Construct a cumulative percentage distribution and…arrow_forward
- The Conch Café, located in Gulf Shores, Alabama, features casual lunches with a great view of the Gulf of Mexico. To accommodate the increase in business during the summer vacation season, Fuzzy Conch, the owner, hires a large number of servers as seasonal help. When he interviews a prospective server, he would like to provide data on the amount a server can earn in tips. He believes that the amount of the bill and the number of diners are both related to the amount of the tip. He gathered the following sample information. Customer Amount of Tip Amount of Bill Number of Diners Customer Amount of Tip Amount of Bill Number of Diners 1 $ 7.00 $ 48.97 5 16 $ 3.30 $ 23.59 2 2 4.50 28.23 4 17 3.50 22.30 2 3 1.00 10.65 1 18 3.25 32.00 2 4 2.40 19.82 3 19 5.40 50.02 4 5 5.00 28.62 3 20 2.25 17.60 3 6 4.25 24.83 2 21 5.50 44.47 4 7 0.50 6.24 1 22 3.00 20.27 2…arrow_forwardThe Conch Café, located in Gulf Shores, Alabama, features casual lunches with a great view of the Gulf of Mexico. To accommodate the increase in business during the summer vacation season, Fuzzy Conch, the owner, hires a large number of servers as seasonal help. When he interviews a prospective server, he would like to provide data on the amount a server can earn in tips. He believes that the amount of the bill and the number of diners are both related to the amount of the tip. He gathered the following sample information. Customer Amount of Tip Amount of Bill Number of Diners Customer Amount of Tip Amount of Bill Number of Diners 1 $ 6.05 $ 73.22 1 16 $ 3.30 $ 23.59 2 2 4.50 28.23 4 17 3.50 22.30 2 3 1.00 10.65 1 18 3.25 32.00 2 4 2.40 19.82 3 19 5.40 50.02 4 5 5.00 28.62 3 20 2.25 17.60 3 6 4.25 24.83 2 21 1.40 41.80 5 7 .50 6.25 1 22 3.00 20.27 2…arrow_forwardFor each problem, select the best response. (a) Does mandatory gun ownership prevent crime? To study this, the number of burglaries committed each month in a small town were recorded for 75 months prior to passage of a bill requiring citizens to own guns and for 56 months after passage of the bill. The goal was to see if the number of burglaries committed was affected by requiring citizens to own guns. The response variable here is A. whether or not gun ownership is required by law. B. the number of burglaries committed. C. the number of guns owned. D. whether or not a burglary was committed by a gun owner. E. None of the above. (b) Can one predict a student's score on the midterm exam in a statistics course from the number of hours the student spent studying for the exam? To explore this, the teacher of the course asks students how many hours they spent studying for the exam and then makes a scatterplot of the time students spent studying and their scores on the exam. In…arrow_forward
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