Statistics for Managers Using Microsoft Excel Instruction and Data Collection.docx

Statistics for Managers Using Microsoft Excel Instruction and Data Collection 1) The process of using sample statistics to draw conclusions about true population parameters is called A) statistical inference. B) the scientific method. C) sampling. D) descriptive statistics. Answer: A Keywords: inferential statistics 2) Those methods involving the collection, presentation, and characterization of a set of data in order to properly describe the various features of that set of data are called A) statistical inference. B) the scientific method. C) sampling. D) descriptive statistics. Answer: D 3) The collection and summarization of the socioeconomic and physical characteristics of the employees of a particular firm is an example of A) inferential statistics. B) descriptive statistics. C) a parameter. D) a statistic. Answer: B 4) The estimation of the population average family expenditure on food based on the sample average expenditure of 1,000 families is an example of A) inferential statistics. B) descriptive statistics. C) a parameter. D) a statistic. Answer: A Keywords: inferential statistics 5) The universe or "totality of items or things" under consideration is called A) a sample. B) a population. C) a parameter. D) a statistic. Answer: B Keywords: population 6) The portion of the universe that has been selected for analysis is called A) a sample. B) a frame. C) a parameter. D) a statistic. Answer: A Keywords: sample 7) A summary measure that is computed to describe a characteristic from only a sample of the population is called A) a parameter. B) a census. C) a statistic. D) the scientific method. Answer: C Keywords: statistic 8) A summary measure that is computed to describe a characteristic of an entire population is called A) a parameter. B) a census. C) a statistic. D) the scientific method. Answer: A Keywords: parameter 9) Which of the following is most likely a population as opposed to a sample? A) respondents to a newspaper survey. B) the first 5 students completing an assignment. C) every third person to arrive at the bank. D) registered voters in a county. Answer: D Keywords: population, sample 10) Which of the following is most likely a parameter as opposed to a statistic? A) The average score of the first five students completing an assignment. B) The proportion of females registered to vote in a county. C) The average height of people randomly selected from a database. D) The proportion of trucks stopped yesterday that were cited for bad brakes. Answer: B Keywords: parameter, statistic 11) Which of the following is not an element of descriptive statistical problems? A) An inference made about the population based on the sample. B) The population or sample of interest. C) Tables, graphs, or numerical summary tools. D) Identification of patterns in the data. Answer: A 12) A study is under way in Yosemite National Forest to determine the adult height of American pine trees. Specifically, the study is attempting to determine what factors aid a tree in reaching heights greater than 60 feet tall. It is estimated that the forest contains 25,000 adult American pines. The study involves collecting heights from 250 randomly selected adult American pine trees and analyzing the results. Identify the population from which the study was sampled. A) The 250 randomly selected adult American pine trees. B) The 25,000 adult American pine trees in the forest. C) All the adult American pine trees taller than 60 feet. D) All American pine trees, of any age, in the forest. Answer: B Keywords: population, sample 13) A study is under way in Yosemite National Forest to determine the adult height of American pine trees. Specifically, the study is attempting to determine what factors aid a tree in reaching heights greater than 60 feet tall. It is estimated that the forest contains 25,000 adult American pines. The study involves collecting heights from 250 randomly selected adult American pine trees and analyzing the results. Identify the variable of interest in the study. A) The age of an American pine tree in Yosemite National Forest. B) The height of an American pine tree in Yosemite National Forest. C) The number of American pine trees in Yosemite National Forest. D) The species of trees in Yosemite National Forest. Answer: B Keywords: variable 14) A study is under way in Yosemite National Forest to determine the adult height of American pine trees. Specifically, the study is attempting to determine what factors aid a tree in reaching heights greater than 60 feet tall. It is estimated that the forest contains 25,000 adult American pines. The study involves collecting heights from 250 randomly selected adult American pine trees and analyzing the results. Identify the sample in the study. A) The 250 randomly selected adult American pine trees. B) The 25,000 adult American pine trees in the forest. C) All the adult American pine trees taller than 60 feet. D) All American pine trees, of any age, in the forest. Answer: A Keywords: population, sample 15) Most analysts focus on the cost of tuition as the way to measure the cost of a college education. But incidentals, such as textbook costs, are rarely considered. A researcher at Drummand University wishes to estimate the textbook costs of first-year students at Drummand. To do so, she monitored the textbook cost of 250 first-year students and found that their average textbook cost was $300 per semester. Identify the population of interest to the researcher. A) All Drummand University students. B) All college students. C) All first-year Drummand University students. D) The 250 students that were monitored. Answer: C Keywords: population, sample 16) Most analysts focus on the cost of tuition as the way to measure the cost of a college education. But incidentals, such as textbook costs, are rarely considered. A researcher at Drummand University wishes to estimate the textbook costs of first-year students at Drummand. To do so, she monitored the textbook cost of 250 first-year students and found that their average textbook cost was $300 per semester. Identify the variable of interest to the researcher. A) The textbook cost of first-year Drummand University students. B) The year in school of Drummand University students. C) The age of Drummand University students. D) The cost of incidental expenses of Drummand University students. Answer: A Keywords: variable 17) Most analysts focus on the cost of tuition as the way to measure the cost of a college education. But incidentals, such as textbook costs, are rarely considered. A researcher at Drummand University wishes to estimate the textbook costs of first-year students at Drummand. To do so, she monitored the textbook cost of 250 first-year students and found that their average textbook cost was $300 per semester. Identify the sample in the study. A) All Drummand University students. B) All college students. C) All first-year Drummand University students. D) The 250 students that were monitored. Answer: D Keywords: population, sample 18) Researchers suspect that the average number of units earned per semester by college students is rising. A researcher at Calendula College wishes to estimate the number of units earned by students during the spring semester at Calendula. To do so, he randomly selects 100 student transcripts and records the number of units each student earned in the spring term. He found that the average number of semester units completed was 12.96 units per student. Identify the population of interest to the researcher. A) All Calendula College students. B) All college students. C) All Calendula College students enrolled in the spring. D) All college students enrolled in the spring. Answer: C Keywords: population, sample 19) The average number of units earned per semester by college students is suspected to be rising. A researcher at Calendula College wishes to estimate the number of units earned by students during the spring semester at Calendula. To do so, he randomly selects 100 student transcripts and records the number of units each student earned in the spring term. Identify the variable of interest to the researcher. A) The number of students enrolled at Calendula College during the spring term. B) The average indebtedness of Calendula College students enrolled in the spring. C) The age of Calendula College students enrolled in the spring. D) The number of units earned by Calendula College students during the spring term. Answer: D Keywords: data, sampling 20) The chancellor of a major university was concerned about alcohol abuse on her campus and wanted to find out the proportion of students at her university who visited campus bars on the weekend before the final exam week. Her assistant took a random sample of 250 students and computed the portion of students in the sample who visited campus bars on the weekend before the final exam. The portion of all students at her university who visited campus bars on the weekend before the final exam week is an example of A) a statistic. B) a population. C) a sample. D) a parameter. Answer: D Keywords: parameter 21) The chancellor of a major university was concerned about alcohol abuse on her campus and wanted to find out the proportion of students at her university who visited campus bars on the weekend before the final exam week. Her assistant took a random sample of 250 students. The portion of students in the sample who visited campus bars on the weekend before the final exam week is an example of ________. A) a population. B) a sample. C) a parameter. D) a statistic. Answer: D Keywords: statistic TABLE 1-1 The manager of the customer service division of a major consumer electronics company is interested in determining whether the customers who have purchased a DVD player made by the company over the past 12 months are satisfied with their products. 22) Referring to Table 1-1, the population of interest is A) all the customers who have bought a DVD player made by the company over the past 12 months. B) all the customers who have bought a DVD player made by the company and brought it in for repair over the past 12 months. C) all the customers who have used a DVD player over the past 12 months. D) all the customers who have ever bought a DVD player made by the company. Answer: A Keywords: population 23) True or False: A population is the totality of items or things under consideration. Answer: TRUE Keywords: population 24) True or False: A sample is the portion of the universe that is selected for analysis. Answer: TRUE Keywords: sample 25) True or False: Problems may arise when statistically unsophisticated users who do not understand the assumptions behind the statistical procedures or their limitations are misled by results obtained from computer software. Answer: TRUE Keywords: statistical package Topics: Section 1.2 & Section 1.4 26) True or False: Managers need an understanding of statistics to be able to present and describe information accurately, draw conclusions about large populations based on small samples, improve processes, and make reliable forecasts. Answer: TRUE Keywords: reasons for learning statistics 27) True or False: A statistic is usually used to provide an estimate for a usually unobserved parameter. Answer: TRUE Keywords: statistic, parameter 28) True or False: A statistic is usually unobservable while a parameter is usually observable. Answer: FALSE Keywords: statistic, parameter, inferential statistic 29) True or False: A professor computed the sample average exam score of 20 students and used it to estimate the average exam score of the 1,500 students taking the exam was an example of inferential statistics. Answer: TRUE 30) True or False: Using the number of registered voters who turned out to vote for the primary in Iowa to predict the number of registered voters who will turn out to vote in Vermont's primary is an example of descriptive statistics. Answer: FALSE 31) True or False: Compiling the number of registered voters who turned out to vote for the primary in Iowa is an example of descriptive statistics. Answer: TRUE 32) The Human Resources Director of a large corporation wishes to develop an employee benefits package and decides to select 500 employees from a list of all (N = 40,000) workers in order to study their preferences for the various components of a potential package. All the employees in the corporation constitute the ________. Answer: population Keywords: population 33) The Human Resources Director of a large corporation wishes to develop an employee benefits package and decides to select 500 employees from a list of all (N = 40,000) workers in order to study their preferences for the various components of a potential package. The 500 employees who will participate in this study constitute the ________. Answer: sample Keywords: sample 34) The Human Resources Director of a large corporation wishes to develop an employee benefits package and decides to select 500 employees from a list of all (N = 40,000) workers in order to study their preferences for the various components of a potential package. The Director will use the data from the sample to compute ________. Answer: statistics Keywords: statistic 35) The Human Resources Director of a large corporation wishes to develop an employee benefits package and decides to select 500 employees from a list of all (N = 40,000) workers in order to study their preferences for the various components of a potential package. Information obtained from the sample will be used to draw conclusions about the true population ________. Answer: parameters Keywords: parameter 36) The Human Resources Director of a large corporation wishes to develop an employee benefits package and decides to select 500 employees from a list of all (N = 40,000) workers in order to study their preferences for the various components of a potential package. In this study, methods involving the collection, presentation, and characterization of the data are called ________. Answer: descriptive statistics/methods 37) The Human Resources Director of a large corporation wishes to develop an employee benefits package and decides to select 500 employees from a list of all (N = 40,000) workers in order to study their preferences for the various components of a potential package. In this study, methods that result in decisions concerning population characteristics based only on the sample results are called ________. Answer: inferential statistics/methods Keywords: inferential statistics 38) Mediterranean fruit flies were discovered in California a few years ago and badly damaged the oranges grown in that state. Suppose the manager of a large farm wanted to study the impact of the fruit flies on the orange crops on a daily basis over a 6-week period. On each day a random sample of orange trees were selected from within a random sample of acres. The daily average number of damaged oranges per tree and the proportion of trees having damaged oranges were calculated. The two main measures calculated each day (i.e., average number of damaged oranges per tree and proportion of trees having damaged oranges) are called ________. Answer: statistics Keywords: statistic 39) Mediterranean fruit flies were discovered in California a few years ago and badly damaged the oranges grown in that state. Suppose the manager of a large farm wanted to study the impact of the fruit flies on the orange crops on a daily basis over a 6-week period. On each day a random sample of orange trees were selected from within a random sample of acres. The daily average number of damaged oranges per tree and the proportion of trees having damaged oranges were calculated. The two main measures calculated each day (i.e., average number of damaged oranges per tree and proportion of trees having damaged oranges) may be used on a daily basis to estimate the respective true population ________. Answer: parameters Keywords: parameters 40) Mediterranean fruit flies were discovered in California a few years ago and badly damaged the oranges grown in that state. Suppose the manager of a large farm wanted to study the impact of the fruit flies on the orange crops on a daily basis over a 6-week period. On each day a random sample of orange trees were selected from within a random sample of acres. The daily average number of damaged oranges per tree and the proportion of trees having damaged oranges were calculated. In this study, drawing conclusions on any one day about the true population characteristics based on information obtained from the sample is called ________. Answer: inferential statistics/methods Keywords: inferential statistics 41) Mediterranean fruit flies were discovered in California a few years ago and badly damaged the oranges grown in that state. Suppose the manager of a large farm wanted to study the impact of the fruit flies on the orange crops on a daily basis over a 6-week period. On each day a random sample of orange trees were selected from within a random sample of acres. The daily average number of damaged oranges per tree and the proportion of trees having damaged oranges were calculated. In this study, the presentation and characterization of the two main measures calculated each day (i.e., average number of damaged oranges per tree and proportion of trees having damaged oranges) is called ________. Answer: descriptive statistics/methods 42) The Quality Assurance Department of a large urban hospital is attempting to monitor and evaluate patient satisfaction with hospital services. Prior to discharge, a random sample of patients is asked to fill out a questionnaire to rate such services as medical care, nursing, therapy, laboratory, food, and cleaning. The Quality Assurance Department prepares weekly reports that are presented at the Board of Directors meetings and extraordinary/atypical ratings are easy to flag. Values computed from the sample results each week are called ________. Answer: statistics Keywords: statistic 43) The Quality Assurance Department of a large urban hospital is attempting to monitor and evaluate patient satisfaction with hospital services. Prior to discharge, a random sample of patients is asked to fill out a questionnaire to rate such services as medical care, nursing, therapy, laboratory, food, and cleaning. The Quality Assurance Department prepares weekly reports that are presented at the Board of Directors meetings and extraordinary/atypical ratings are easy to flag. True population characteristics estimated from the sample results each week are called ________. Answer: parameters Keywords: parameter 44) The Commissioner of Health in New York State wanted to study malpractice litigation in New York. A sample of 31 thousand medical records was drawn from a population of 2.7 million patients who were discharged during the year 2009. The proportion of malpractice claims filed from the sample of 31 thousand patients is a ________. Answer: statistic Keywords: statistic 45) The Commissioner of Health in New York State wanted to study malpractice litigation in New York. A sample of 31 thousand medical records was drawn from a population of 2.7 million patients who were discharged during the year 2009. The true proportion of malpractice claims filed from the population of 2.7 million patients is a ________. Answer: parameter Keywords: parameter 46) The Commissioner of Health in New York State wanted to study malpractice litigation in New York. A sample of 31 thousand medical records was drawn from a population of 2.7 million patients who were discharged during the year 2009. Using the information obtained from the sample to predict population characteristics with respect to malpractice litigation is an example of ________. Answer: inferential statistics 47) The Commissioner of Health in New York State wanted to study malpractice litigation in New York. A sample of 31 thousand medical records was drawn from a population of 2.7 million patients who were discharged during the year 2009. The collection, presentation, and characterization of the data from patient medical records are examples of ________. Answer: descriptive statistics/methods Data and Statistics Solutions: 1. Statistics can be referred to as numerical facts. In a broader sense, statistics is the field of study dealing with the collection, analysis, presentation and interpretation of data. 2. a. The ten elements are the ten cars b. 5 variables: Size, Cylinders, City MPG, Highway MPG, and Fuel c. Categorical variables: Size and Fuel Quantitative variables: Cylinders, City MPG, and Highway MPG d. Variable Measurement Scale Size Ordinal Cylinders Ratio City MPG Ratio Highway MPG Ratio Fuel Nominal 3. a. Average mpg for city driving = 182/10 = 18.2 mpg b. Average mpg for highway driving = 261/10 = 26.1 mpg On average, the miles per gallon for highway driving is 26.1 – 18.2 = 7.9 mpg greater compared to city driving. c. 3 of 10 or 30% have four cylinder engines d. 6 of 10 or 60% use regular fuel 4. a. The seven elements are the seven schools shown b. 5 variables: State, Campus Setting, Endowment, Applicants Admitted, and NCAA Division c. Categorical variables: State, Campus Setting, and NCAA Division Quantitative variables: Endowment and Applicants Admitted 5. a. Average endowment = 74.6/7 = $10.657 billion b. Average percentage admitted = 111/7 = 15.86% c. 3 of 7 or 42.9% have NCAA Division III varsity teams d. 3 of 7 or 42.9% have a City: Midsize campus setting 6. a. Quantitative b. Categorical c. Categorical d. Quantitative e. Categorical 7. a. Although the data are recorded as numbers, the numbers are codes for the ratings of Fair (1), Average (2), Good (3) and Excellent (4). Thus the variables are categorical with each data value corresponding to a rating category for the variable. b. The data may also be ranked in order of the quality. A higher number indicates a higher rating on a scale from Fair (1) to Excellent (4). Since the data can be ranked or ordered, the scale of measurement is ordinal. 8. a. 1015 b. Categorical c. Percentages d. .10(1015) = 101.5 101 or 102 respondents said the Federal Bank is doing a good job. 9. a. Categorical b. 30 of 71; 42.3% 10. a. Quantitative; ratio scale of measurement b. Categorical; nominal scale of measurement c. Categorical; ordinal scale of measurement since the responses can be ordered from earliest (high school) to latest (retirement) d. Quantitative; ratio scale of measurement e. Categorical; nominal scale of measurement 11. a. Quantitative; ratio b. Categorical; ordinal c. Categorical; ordinal (assuming employees can be ranked by classification) d. Quantitative; ratio e. Categorical; nominal 12. a. The population is all visitors coming to the state of Hawaii. b. Since airline flights carry the vast majority of visitors to the state, the use of questionnaires for passengers during incoming flights is a good way to reach this population. The questionnaire actually appears on the back of a mandatory plants and animals declaration form that passengers must complete during the incoming flight. A large percentage of passengers complete the visitor information questionnaire. c. Questions 1 and 4 provide quantitative data indicating the number of visits and the number of days in Hawaii. Questions 2 and 3 provide categorical data indicating the categories of reason for the trip and where the visitor plans to stay. 13. a. Federal spending measured in trillions of dollars b. Quantitative c. Time series d. Federal spending has increased over time 14. a. b. According to the CSM data, Toyota surpasses General Motors as the biggest auto manufacturer in the world in 2006. In 2006, Toyota manufactured approximately (9.1 – 8.9) = .2 million or 200,000 more vehicles than General Motors. The gap is expected to widen to 800,000 vehicles in 2007. General Motors is the only manufacturer showing a decline in vehicle production over the four year period. c. The following is a bar chart of cross-sectional data as it shows the number of vehicles manufactured in 2007. 15. a. Quantitative – number of new drugs approved b. Time series from 1996 to 2003 c. 18 d. 2002; 16 new drugs e. Over the eight-year period, the number of new drugs approved by the FDA declined. From approximately 50 new drugs approved in 1996, the most recent years are showing only 16 to 18 new drugs approved. 16. The answer to this exercise depends upon the time series of the average price per gallon of conventional regular gasoline since April 2009. Contact the website www.eia.doe.gov to obtain the more recent time series data. In the spring of 2009, the average price per gallon was once again increasing. A continuation of the usual summer peak in gasoline prices was anticipated. 17. Internal data on salaries of other employees can be obtained from the personnel department. External data might be obtained from the Department of Labor or industry associations. 18. a. or 36% b. 44% of 430 = .44(430) = 189 business travelers c. Categorical data with categories online travel site, travel agent, direct with airline/hotel, other. 19. a. All subscribers of Business Week in North America at the time the survey was conducted. b. Quantitative c. Categorical (yes or no) d. Crossectional - all the data relate to the same time. e. Using the sample results, we could infer or estimate 59% of the population of subscribers have an annual income of $75,000 or more and 50% of the population of subscribers have an American Express credit card. 20. a. 43% of managers were bullish or very bullish. 21% of managers expected health care to be the leading industry over the next 12 months. b. We estimate the average 12-month return estimate for the population of investment managers to be 11.2%. c. We estimate the average over the population of investment managers to be 2.5 years. 21. a. The two populations are the population of women whose mothers took the drug DES during pregnancy and the population of women whose mothers did not take the drug DES during pregnancy. b. It was a survey. c. 63 / 3.980 = 15.8 women out of each 1000 developed tissue abnormalities. d. The article reported “twice” as many abnormalities in the women whose mothers had taken DES during pregnancy. Thus, a rough estimate would be 15.8/2 = 7.9 abnormalities per 1000 women whose mothers had not taken DES during pregnancy. e. In many situations, disease occurrences are rare and affect only a small portion of the population. Large samples are needed to collect data on a reasonable number of cases where the disease exists. 22. a. The population consists of all customers of the chain’s stores in Charlotte, North Carolina. b. Some of the ways that could used to collect the data are as follows: Customers entering or leaving the store could be surveyed A survey could be mailed to customers who have a shopper’s club card for the stores Customers could be given a printed survey when they check out Customers could be given a coupon that asks them to complete a brief on-line survey; if they do, they will receive a 5% discount on their next shopping trip. 23. a. Nielsen is attempting to measure the popularity of each television program by showing the percentage of households that are watching the program. b. All households with televisions in the United States. c. A census of the population is impossible. A sample provides timely information in that the ratings and share data can be obtained weekly. In addition, the sample saves data collection costs. d. The cancellation or renewal of television programs, advertising cost rates for the television programs and the scheduling of television programs are often based on the Nielsen information. 24. a. This is a statistically correct descriptive statistic for the sample. b. An incorrect generalization since the data was not collected for the entire population. c. An acceptable statistical inference based on the use of the word “estimate.” d. While this statement is true for the sample, it is not a justifiable conclusion for the entire population. e. This statement is not statistically supportable. While it is true for the particular sample observed, it is entirely possible and even very likely that at least some students will be outside the 65 to 90 range of grades. 25. a. There are five variables: Exchange, Ticker Symbol, Market Cap, Price/Earnings Ratio and Gross Profit Margin. b. Categorical variables: Exchange and Ticker Symbol Quantitative variables: Market Cap, Price/Earnings Ratio, Gross Profit Margin c. Exchange variable: Exchange Frequency Percent Frequency AMEX 5 (5/25) 20% NYSE 3 (3/25) 12% OTC 17 (17/25) 68% 25 d. Gross Profit Margin variable: Gross Profit Margin Frequency 0.0 – 14.9 2 15.0 – 29.9 6 30.0 – 44.9 8 45.0 – 59.9 6 60.0 – 74.9 3 e. Sum the Price/Earnings Ratio data for all 25 companies. Sum = 505.4 Average Price/Earnings Ratio = Sum/25 = 505.4/25 = 20.2