StatisticsforBusinessandEconomicsSolutionsManual解答手冊.doc

solutions manual to accompanystatistics for businessand economicseighth editiondavid r. andersonuniversity of cincinnatidennis j. sweeneyuniversity of cincinnatithomas a. williamsrochester institute of technology 2002 by south-western/thomson learningcincinnati, ohiocontentschapter1.data and statistics2.descriptive statistics: tabular and graphical approaches3.descriptive statistics: numerical methods4.introduction to probability5.discrete probability distributions6.continuous probability distributions7.sampling and sampling distributions8.interval estimation9.hypothesis testing10.statistical inference about means and proportions with two populations11.inferences about population variances12.tests of goodness of fit and independence13.analysis of variance and experimental design14.simple linear regression15.multiple regression16.regression analysis: model building17.index numbers18.forecasting19.nonparametric methods20.statistical methods for quality control21.sample surveyprefacethe purpose of statistics for business and economics is to provide students, primarily in the fields of business administration and economics, with a sound conceptual introduction to the field of statistics and its many applications. the text is applications-oriented and has been written with the needs of the nonmathematician in mind. the solutions manual furnishes assistance by identifying learning objectives and providing detailed solutions for all exercises in the text.acknowledgementswe would like to provide special recognition to catherine j. williams for her efforts in preparing the solutions manual. david r. andersondennis j. sweeneythomas a. williamschapter 1data and statisticslearning objectives1.obtain an appreciation for the breadth of statistical applications in business and economics.2.understand the meaning of the terms elements, variables, and observations as they are used in statistics.3.obtain an understanding of the difference between qualitative, quantitative, crossectional and time series data.4.learn about the sources of data for statistical analysis both internal and external to the firm.5.be aware of how errors can arise in data.6.know the meaning of descriptive statistics and statistical inference.7.be able to distinguish between a population and a sample.8.understand the role a sample plays in making statistical inferences about the population.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.9b.4c. country and room rate are qualitative variables; number of rooms and the overall score are quantitative variables.d. country is nominal; room rate is ordinal; number of rooms and overall score are ratio.3.a.average number of rooms = 808/9 = 89.78 or approximately 90 roomsb.2 of 9 are located in england; approximately 22%c.4 of 9 have a room rate of $; approximately 44%4.a.10b.fortune 500 largest u.s. industrial corporationsc.average revenue = $142,275.9/10 = $14,227.59 milliond.using the sample average, statistical inference would let us estimate the average revenue for the population of 500 corporations as $14,227.59 million.5.a.3b.industry code is qualitative; revenues and profit are quantitative.c.average profit = 10,652.1/10 = $1065.21 milliond.8 of 10 had a profit over $100 million; 80%e.1 of 10 had an industry code of 3; 10%6.questions a, c, and d are quantitative.questions b and e are qualitative.7.a.the data are numeric and the variable is qualitative.b.nominal8.a.2,013b.qualitativec.percentages since we have qualitative datad.(0.28)(2013) = 563.64 must have been 563 or 564.9.a.qualitativeb.30 of 71; 42.3%10.a.quantitative; ratiob.qualitative; nominalc.qualitative (note: rank is a numeric label that identifies the position of a student in the class. rank does not indicate how much or how many and is not quantitative.); ordinald.qualitative; nominale.quantitative; ratio11.a.quantitative; ratiob.qualitative; ordinalc.qualitative; ordinal (assuming employees can be ranked by classification)d.quantitative; ratioe.qualitative; nominal12.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 qualitative data indicating the categories of reason for the trip and where the visitor plans to stay.13.a.quantitativeb.time series with 7 observationsc.number of riverboat casinos.d.time series shows a rapid increase; an increase would be expected in 1998, but it appears that the rate of increase is slowing.14.a.4b.all four variables are quantitative.c.time series data for 1993 to 1996.15.crossectional data. it is based on the 1996 performance data that was available april 1997.16.a.we would like to see data from product taste tests and test marketing the product.b.such data would be obtained from specially designed statistical studies.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.(48/120)100% = 40% in the sample died from some form of heart disease. this can be used as an estimate of the percentage of all males 60 or older who die of heart disease.b.the data on cause of death is qualitative.19.a.all subscribers of business week at the time the 1996 survey was conducted.b.quantitativec.qualitative (yes or no)d.crossectional - 1996 was the time of the survey.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.56% of market belonged to a.c. nielsen$387,325 is the average amount spent per categoryb.3.73c.$387,32521.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.all adult viewers reached by the denver, colorado television station.b.the viewers contacted in the telephone survey.c.a sample. it would clearly be too costly and time consuming to try to contact all viewers.23.a.percent of television sets that were tuned to a particular television show and/or total viewing audience.b.all television sets in the united states which are available for the viewing audience. note this would not include television sets in store displays.c.a portion of these television sets. generally, individual households would be contacted to determine which programs were being viewed.d.the cancellation of programs, the scheduling of programs, and advertising cost rates.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.chapter 2descriptive statistics: tabular and graphical methodslearning objectives1.learn how to construct and interpret summarization procedures for qualitative data such as : frequency and relative frequency distributions, bar graphs and pie charts.2.learn how to construct and interpret tabular summarization procedures for quantitative data such as:frequency and relative frequency distributions, cumulative frequency and cumulative relative frequency distributions.3.learn how to construct a dot plot, a histogram, and an ogive as graphical summaries of quantitative data.4.be able to use and interpret the exploratory data analysis technique of a stem-and-leaf display.5.learn how to construct and interpret cross tabulations and scatter diagrams of bivariate data.2 - 7solutions:1.classfrequencyrelative frequencya6060/120 = 0.50b 2424/120 = 0.20c 3636/120 = 0.30120 1.00 2.a.1 - (.22 + .18 + .40) = .20b.20(200) = 40c/dclassfrequencypercent frequencya.22(200) = 44 22b.18(200) = 36 18c.40(200) = 80 40d.20(200) = 40 20total2001003.a.360 x 58/120 = 174b.360 x 42/120 = 126c.d.4.a.the data are qualitative.b.tv showfrequencypercent frequencymillionaire2448frasier1530chicago hope714charmed48total:50100c.d.millionaire has the largest market share. frasier is second. 5.a.majorrelative frequencypercent frequencymanagement55/216 = 0.25 25accounting51/216 = 0.24 24 finance28/216 = 0.13 13marketing82/216 = 0.38 38total1.00100b.c.pie chart6.a.bookfrequencypercent frequency7 habits1016.66millionaire1626.67motley915.00dad1321.67wsj guide610.00other610.00total:60100.00the ernst & young tax guide 2000 with a frequency of 3, investing for dummies with a frequency of 2, and what color is your parachute? 2000 with a frequency of 1 are grouped in the other category.b.the rank order from first to fifth is: millionaire, dad, 7 habits, motley, and wsj guide.c.the percent of sales represented by the millionaire next door and rich dad, poor dad is 48.33%. 7.ratingfrequencyrelative frequencyoutstanding190.38very good130.26good100.20average 60.12poor 20.04501.00management should be pleased with these results. 64% of the ratings are very good to outstanding. 84% of the ratings are good or better. comparing these ratings with previous results will show whether or not the restaurant is making improvements in its ratings of food quality.8.a.positionfrequencyrelative frequencypitcher170.309catcher 40.0731st base 50.0912nd base 40.0733rd base 20.036shortstop 50.091left field 60.109center field 50.091right field 70.127551.000b.pitchers (almost 31%)c.3rd base (3 - 4%)d.right field (almost 13%)e.infielders (16 or 29.1%) to outfielders (18 or 32.7%)9.a/b.starting time frequencypercent frequency7:003157:304208:004208:307359:0021020100c.bar graphd.e.the most preferred starting time is 8:30 a.m. starting times of 7:30 and 8:00 a.m. are next.10.a.the data refer to quality levels of poor, fair, good, very good and excellent.b.ratingfrequencyrelative frequencypoor2 0.03fair4 0.07good12 0.20very good24 0.40excellent18 0.3060 1.00c.bar graphpie chartd.the course evaluation data indicate a high quality course. the most common rating is very good with the second most common being excellent.11.classfrequencyrelative frequencypercent frequency12-14 20.050 5.015-17 80.200 20.018-20110.275 27.521-23100.250 25.524-26 90.225 22.5total401.000100.012.classcumulative frequencycumulative relative frequencyless than or equal to 1910 .20less than or equal to 2924 .48less than or equal to 3941 .82less than or equal to 4948.96less than or equal to 59501.0013.14. a.b/c.classfrequencypercent frequency 6.0 - 7.94 20 8.0 - 9.9 2 1010.0 - 11.9 8 4012.0 - 13.9 3 1514.0 - 15.9 3 152010015.a/b.waiting timefrequencyrelative frequency0 - 440.205 - 9 80.4010 - 14 50.2515 - 19 20.1020 - 24 10.05totals201.00c/d.waiting timecumulative frequencycumulative relative frequencyless than or equal to 440.20less than or equal to 9120.60less than or equal to 14170.85less than or equal to 19190.95less than or equal to 24201.00e.12/20 = 0.6016.a.stock price ($)frequencyrelative frequencypercent frequency10.00 - 19.99100.404020.00 - 29.9940.161630.00 - 39.9960.242440.00 - 49.9920.08850.00 - 59.9910.04460.00 - 69.9920.088total251.00100many of these are low priced stocks with the greatest frequency in the $10.00 to $19.99 range.b.earnings per share ($)frequencyrelative frequencypercent frequency-3.00 to -2.0120.088-2.00 to -1.0100.000-1.00 to -0.0120.0880.00 to 0.9990.36361.00 to 1.9990.36362.00 to 2.9930.1212total251.00100the majority of companies had earnings in the $0.00 to $2.00 range. four of the companies lost money.17.call durationfrequencyrelative frequency2 - 3.9 50.254 - 5.9 90.456 - 7.9 40.208 - 9.9 00.0010 - 11.9 20.10totals201.00histogram18.a.lowest salary: $93,000highest salary: $178,000b.salary ($1000s)frequencyrelative frequencypercent frequency 91-10540.08 8106-12050.10 10121-135110.22 22136-150180.36 36151-16590.18 18166-18030.06 6total501.00100c.proportion $135,000 or less: 20/50.d.percentage more than $150,000: 24%e.19.a/b.numberfrequencyrelative frequency140 - 149 20.10150 - 159 70.35160 - 169 30.15170 - 179 60.30180 - 189 10.05190 - 199 10.05totals201.00c/d.numbercumulative frequencycumulative relative frequencyless than or equal to 149 20.10less than or equal to 159 90.45less than or equal to 169120.60less than or equal to 179180.90less than or equal to 189190.95less than or equal to 199201.00e.20.a.the percentage of people 34 or less is 20.0 + 5.7 + 9.6 + 13.6 = 48.9.b.the percentage of the population that is between 25 and 54 years old inclusively is 13.6 + 16.3 + 13.5 = 43.4c.the percentage of the population over 34 years old is16.3 + 13.5 + 8.7 + 12.6 = 51.1d.the percentage less than 25 years old is 20.0 + 5.7 + 9.6 = 35.3. so there are (.353)(275) = 97.075 million people less than 25 years old.e.an estimate of the number of retired people is (.5)(.087)(275) + (.126)(275) = 46.6125 million.21.a/b.computer usage (hours)frequencyrelative frequency0.0-2.950.103.0-5.9280.566.0-8.980.169.0-11.960.1212.0-14.930.06total501.00c.d.e.the majority of the computer users are in the 3 to 6 hour range. usage is somewhat skewed toward the right with 3 users in the 12 to 15 hour range.22.23.leaf unit = 0.124.leaf unit = 1025.26.leaf unit = 0.104 7 8 9 911 2 920 0 1 3 5 5 6 834 948567127.28.a.05 8 11 1 3 3 4 415 6 7 8 9 922 3 3 3 5 526 8336 7 7 94047 85560b.2000 p/e forecastfrequencypercent frequency5 - 926.710 - 14620.015 - 19620.020 - 24620.025 - 2926.730 - 3400.035 - 39413.340 - 4413.345 - 4926.750 - 5400.055 - 5900.060 - 6413.3total30100.029.a.b.c.d.category a values for x are always associated wit