商务统计导论全套课件440p.ppt

1、商务统计导论全套课件440pCHAPTER 1:A Preview of Business Statisticsto accompanyIntroduction to Business Statisticsfourth edition,by Ronald M.WeiersPresentation by Priscilla Chaffe-Stengel Donald N.Stengel 2002 The Wadsworth GroupChapter 1-Key TermslCollection,summarization,analysis,and reporting of numerical f

2、indingslStatistics-Two UsagesA.The study of statisticsB.Statistics as reported sample measures1.Descriptive 2.Inferential 2002 The Wadsworth GroupChapter 1-Key TermsInferential Statistics POPULATION SAMPLE How Taken Census Selected Subset Measure Parameter Statistic 2002 The Wadsworth Group Types of

3、 VariableslQualitative VariablesAttributes,categoriesExamples:male/female,registered to vote/not,ethnicity,eye color.lQuantitative VariablesDiscrete-usually take on integer values but can take on fractions when variable allows-counts,how manyContinuous-can take on any value at any point along an int

4、erval-measurements,how much 2002 The Wadsworth GroupExample:Types of VariablesProblem 1.16lFor each of the following,indicate whether the appropriate variable would be qualitative or quantitative.If the variable is quantitative,indicate whether it would be discrete or continuous.2002 The Wadsworth G

5、roupProblem 1.16la)Whether you own an RCA Colortrak television setlb)Your status as a full-time or a part-time studentlc)Number of people who attended your schools graduation last yearlQualitative Variabletwo levels:yes/nono measurementlQualitative Variabletwo levels:full/partno measurementlQuantita

6、tive,Discrete Variablea countable numberonly whole numbers 2002 The Wadsworth GroupProblem 1.16,continuedld)The price of your most recent haircutle)Sams travel time from his dorm to the Student UnionlQuantitative,Discrete Variablea countable numberonly whole numberslQuantitative,Continuous Variablea

7、ny numbertime is measuredcan take on any value greater than zero 2002 The Wadsworth GroupProblem 1.16,continuedlf)The number of students on campus who belong to a social fraternity or sororitylQuantitative,Discrete Variablea countable numberonly whole numbers 2002 The Wadsworth GroupScales of Measur

8、ementlNominal Scale-Labels represent various levels of a categorical variable.lOrdinal Scale-Labels represent an order that indicates either preference or ranking.lInterval Scale-Numerical labels indicate order and distance between elements.There is no absolute zero and multiples of measures are not

9、 meaningful.lRatio Scale-Numerical labels indicate order and distance between elements.There is an absolute zero and multiples of measures are meaningful.2002 The Wadsworth GroupExample:Scales of MeasurementProblem 1.20lBill scored 1200 on the Scholastic Aptitude Test and entered college as a physic

10、s major.As a freshman,he changed to business because he thought it was more interesting.Because he made the deans list last semester,his parents gave him$30 to buy a new Casio calculator.Identify at least one piece of information in the:2002 The Wadsworth GroupProblem 1.20,continuedla)nominal scale

11、of measurement.l1.Bill is going to college.2.Bill will buy a Casio calculator.3.Bill was a physics major.4.Bill is a business major.5.Bill was on the deans list.2002 The Wadsworth GroupProblem 1.20,continuedlb)ordinal scale of measurementlc)interval scale of measurementld)ratio scale of measurementl

12、Bill is a freshman.lBill earned a 1200 on the SAT.lBills parents gave him$30.2002 The Wadsworth GroupCHAPTER 2:Visual Description of Datato accompanyIntroduction to Business Statisticsfourth edition,by Ronald M.WeiersPresentation by Priscilla Chaffe-Stengel Donald N.Stengel 2002 The Wadsworth GroupC

13、hapter 2-Learning ObjectiveslConvert raw data into a data array.lConstruct:a frequency distribution.a relative frequency distribution.a cumulative relative frequency distribution.lConstruct a stem-and-leaf diagram.lVisually represent data by using graphs and charts.2002 The Wadsworth GroupChapter 2-

14、Key TermslData arrayAn orderly presentation of data in either ascending or descending numerical order.lFrequency DistributionA table that represents the data in classes and that shows the number of observations in each class.2002 The Wadsworth GroupChapter 2-Key TermslFrequency DistributionClass-The

15、 categoryFrequency-Number in each classClass limits-Boundaries for each classClass interval-Width of each classClass mark-Midpoint of each class 2002 The Wadsworth GroupSturges rulelHow to set the approximate number of classes to begin constructing a frequency distribution.where k=approximate number

16、 of classes to use andn=the number of observations in the data set.2002 The Wadsworth Groupkn 1 332210.(log)How to Construct aFrequency Distribution1.Number of classes Choose an approximate number of classes for your data.Sturges rule can help.2.Estimate the class interval Divide the approximate num

17、ber of classes(from Step 1)into the range of your data to find the approximate class interval,where the range is defined as the largest data value minus the smallest data value.3.Determine the class intervalRound the estimate(from Step 2)to a convenient value.2002 The Wadsworth GroupHow to Construct

18、 aFrequency Distribution,cont.4.Lower Class LimitDetermine the lower class limit for the first class by selecting a convenient number that is smaller than the lowest data value.5.Class LimitsDetermine the other class limits by repeatedly adding the class width(from Step 2)to the prior class limit,st

19、arting with the lower class limit(from Step 3).6.Define the classesUse the sequence of class limits to define the classes.2002 The Wadsworth GroupConverting to a Relative Frequency Distribution1.Retain the same classes defined in the frequency distribution.2.Sum the total number of observations acro

20、ss all classes of the frequency distribution.3.Divide the frequency for each class by the total number of observations,forming the percentage of data values in each class.2002 The Wadsworth GroupForming a Cumulative Relative Frequency Distribution1.List the number of observations in the lowest class

21、.2.Add the frequency of the lowest class to the frequency of the second class.Record that cumulative sum for the second class.3.Continue to add the prior cumulative sum to the frequency for that class,so that the cumulative sum for the final class is the total number of observations in the data set.

22、2002 The Wadsworth GroupForming a Cumulative Relative Frequency Distribution,cont.4.Divide the accumulated frequencies for each class by the total number of observations-giving you the percent of all observations that occurred up to an including that class.lAn Alternative:Accrue the relative frequen

23、cies for each class instead of the raw frequencies.Then you dont have to divide by the total to get percentages.2002 The Wadsworth GroupExample:Problem 2.53lThe average daily cost to community hospitals for patient stays during 1993 for each of the 50 U.S.states was given in the next table.a)Arrange

24、 these into a data array.b)Construct a stem-and-leaf display.*)Approximately how many classes would be appropriate for these data?*not in textbookc&d)Construct a frequency distribution.State interval width and class mark.e)Construct a histogram,a relative frequency distribution,and a cumulative rela

25、tive frequency distribution.2002 The Wadsworth GroupProblem 2.53-The DataAL$775HI 823MA 1,036NM 1,046SD 506AK 1,136ID 659MI 902NY 784TN 859AZ 1,091IL 917MN 652NC 763TX 1,010AR 678IN 898MS 555ND 507UT 1,081CA 1,221IA 612MO 863OH 940VT 676CO 961KS 666MT 482OK 797VA 830CT 1,058KY 703NE 626OR 1,052WA 1,

26、143DE 1,024LA 875NV 900PA 861WV 701FL 960ME 738NH 976RI 885WI 744GA 775MD 889NJ 829SC 838WY 537 2002 The Wadsworth GroupProblem 2.53-(a)Data ArrayCA 1,221TX 1,010RI 885NY 784KS 666WA 1,143NH 976LA 875AL 775ID 659AK 1,136CO 961MO 863GA 775MN 652AZ 1,091FL 960PA 861NC 763NE 626UT 1,081CH 940TN 859WI 7

27、44IA 612CT 1,058IL 917SC 838ME 738MS 555OR 1,052MI 902VA 830KY 703WY 537NM 1,046NV 900NJ 829WV 701ND 507MA 1,036IN 898HI 823AR 678SD 506DE 1,024MD 889OK 797VT 676MT 482 2002 The Wadsworth GroupProblem 2.53-(b)The Stem-and-Leaf DisplayStem-and-Leaf DisplayN=50Leaf Unit:100 11221 21143,36 81091,81,58,

28、52,46,36,24,10 7 976,61,60,40,17,02,00(11)898,89,85,75,63,61,59,38,30,29,23 9 797,84,75,75,63,44,38,03,01 7 678,76,66,59,52,26,12 4 555,37,07,06 1 482Range:$482-$1,221 2002 The Wadsworth GroupProblem 2.53-ContinuedlTo approximate the number of classes we should use in creating the frequency distribu

29、tion,use Sturges Rule,n=50:Sturges rule suggests we use approximately 7 classes.2002 The Wadsworth Groupk13.322(log10n)13.322(log1050)13.322(1.69897)15.6446.6447Constructing the Frequency DistributionlStep 1.Number of classesSturges Rule:approximately 7 classes.The range is:$1,221$482=$739$739/7-$10

30、6 and$739/8-$92l Steps 2&3.The Class Interval So,if we use 8 classes,we can make each class$100 wide.2002 The Wadsworth GroupConstructing the Frequency DistributionlStep 4.The Lower Class LimitIf we start at$450,we can cover the range in 8 classes,each class$100 in width.The first class:$450 up to$5

31、50lSteps 5&6.Setting Class Limits$450 up to$550$850 up to$950$550 up to$650$950 up to$1,050$650 up to$750$1,050 up to$1,150$750 up to$850$1,150 up to$1,250 2002 The Wadsworth GroupProblem 2.53-(c)&(d)Average daily cost NumberMark$450 under$5504$500$550 under$650 3$600$650 under$750 9$700$750 under$8

32、50 9$800$850 under$950 11$900$950 under$1,050 7$1,000$1,050 under$1,150 6$1,100$1,150 under$1,250 1$1,200Interval width:$100 2002 The Wadsworth GroupProblem 2.53-(e)The Histogram 2002 The Wadsworth Group024681012500600700800900100011001200Problem 2.53-The Relative Frequency DistributionAverage daily

33、 cost Number Rel.Freq.$450 under$550 44/50=.08$550 under$650 33/50=.06$650 under$750 99/50=.18$750 under$850 99/50=.18$850 under$950 11 11/50=.22$950 under$1,050 77/50=.14$1,050 under$1,150 66/50=.12$1,150 under$1,250 11/50=.02 2002 The Wadsworth GroupProblem 2.53-(e)The Percentage Polygon 2002 The

34、Wadsworth Group00.050.10.150.20.250200400600800100012001400Problem 2.53-The Cumulative Frequency DistributionAverage daily cost Number Cum.Freq.$450 under$5504 4$550 under$650 3 7$650 under$750 916$750 under$850 925$850 under$950 1136$950 under$1,050 743$1,050 under$1,150 649$1,150 under$1,250 150 2

35、002 The Wadsworth GroupProblem 2.53-The Cumulative Relative Frequency DistributionAverage daily cost Cum.Freq.Cum.Rel.Freq.$450 under$550 44/50=.02$550 under$650 77/50=.14$650 under$750 16 16/50=.32$750 under$850 25 25/50=.50$850 under$95036 36/50=.72$950 under$1,050 43 43/50=.86$1,050 under$1,150 4

36、9 49/50=.98$1,150 under$1,250 50 50/50=1.00 2002 The Wadsworth GroupProblem 2.53-(e)The Percentage Ogive(Less Than)05101520253035404550020040060080010001200 2002 The Wadsworth GroupThe Scatter DiagramlA scatter diagram is a two-dimensional plot of data representing values of two quantitative variabl

37、es.x,the independent variable,on the horizontal axisy,the dependent variable,on the vertical axislFour ways in which two variables can be related:1.Direct2.Inverse3.Curvilinear4.No relationship 2002 The Wadsworth GroupAn Example:Problem 2.38lFor 6 local offices of a large tax preparation firm,the fo

38、llowing data describe x=service revenues and y=expenses for supplies,freight,postage,etc.Draw a scatter diagram representing the data.Does there appear to be any relationship between the variables?If so,is the relationship direct or inverse?2002 The Wadsworth GroupProblem 2.38,continuedScatter Plot

39、with Trend Line15.017.019.021.023.025.0200.0300.0400.0500.0600.0 x=Service Revenue(thous)y=Office Expenses(thous)2002 The Wadsworth GroupThere appears to be a direct relationship betweenthe service revenue and the office expenses incurred.CHAPTER 3:Statistical Description of Datato accompanyIntroduc

40、tion to Business Statisticsfourth edition,by Ronald M.WeiersPresentation by Priscilla Chaffe-Stengel Donald N.Stengel 2002 The Wadsworth GroupChapter 3-Learning ObjectiveslDescribe data using measures of central tendency and dispersion:for a set of individual data values,andfor a set of grouped data

41、.lConvert data to standardized values.lUse the computer to visually represent data.lUse the coefficient of correlation to measure association between two quantitative variables.2002 The Wadsworth GroupChapter 3-Key TermslMeasures of Central Tendency,The CenterlMean,population;,samplelWeighted MeanlM

42、edianlMode(Note comparison of mean,median,and mode)x 2002 The Wadsworth GroupChapter 3-Key TermslMeasures of Dispersion,The SpreadlRangelMean absolute deviationlVariance(Note the computational difference between s2 and s2.)lStandard deviationlInterquartile rangelInterquartile deviationlCoefficient o

43、f variation 2002 The Wadsworth GroupChapter 3-Key TermslMeasures of Relative PositionlQuantilesQuartilesDecilesPercentileslResidualslStandardized values 2002 The Wadsworth GroupChapter 3-Key TermslMeasures of AssociationlCoefficient of correlation,rDirection of the relationship:direct(r 0)or inverse

44、(r 0)Strength of the relationship:When r is close to 1 or 1,the linear relationship between x and y is strong.When r is close to 0,the linear relationship between x and y is weak.When r=0,there is no linear relationship between x and y.lCoefficient of determination,r2The percent of total variation i

45、n y that is explained by variation in x.2002 The Wadsworth GroupThe Center:MeanlMeanArithmetic average=(sum all values)/#of valuesPopulation:=(Sxi)/NSample:=(Sxi)/nBe sure you know how to get the value easily from your calculator and computer softwares.Problem:Calculate the average number of truck s

46、hipments from the United States to five Canadian cities for the following data given in thousands of bags:Montreal,64.0;Ottawa,15.0;Toronto,285.0;Vancouver,228.0;Winnipeg,45.0 (Ans:127.4)x 2002 The Wadsworth GroupThe Center:Weighted MeanlWhen what you have is grouped data,compute the mean using =(Sw

47、ixi)/SwiProblem:Calculate the average profit from truck shipments,United States to Canada,for the following data given in thousands of bags and profits per thousand bags:Montreal64.0Ottawa 15.0Toronto 285.0$15.00$13.50$15.50 Vancouver 228.0Winnipeg 45.0$12.00$14.00(Ans:$14.04 per thous.bags)2002 The

48、 Wadsworth GroupThe Center:MedianlTo find the median:1.Put the data in an array.2A.If the data set has an ODD number of numbers,the median is the middle value.2B.If the data set has an EVEN number of numbers,the median is the AVERAGE of the middle two values.(Note that the median of an even set of d

49、ata values is not necessarily a member of the set of values.)lThe median is particularly useful if there are outliers in the data set,which otherwise tend to sway the value of an arithmetic mean.2002 The Wadsworth GroupThe Center:ModelThe mode is the most frequent value.lWhile there is just one valu

50、e for the mean and one value for the median,there may be more than one value for the mode of a data set.lThe mode tends to be less frequently used than the mean or the median.2002 The Wadsworth GroupComparing Measures ofCentral TendencylIf mean=median=mode,the shape of the distribution is symmetric.