The fifth edition of Statistics for Business and Economics provides an understanding to support good statistical analysis and decision making. The importance of statistical analysis for business and economics has rapidly increased with the expansion of computer capabilities and electronic transfer of data. Data is collected routinely from all business, government, and non-profit activities. Keys to success in this fast paced and expanding world include correct statistical analysis, interpretation of output, an understanding of complex processes, and the use of computer resources.
FEATURES RETAINED FROM PREVIOUS EDITIONS
The previous editions of Statistics for Business and Economics were known for being unerring in accuracy and statistical precision as well as for their position at a mathematically higher level than most business statistics textbooks. The fifth edition of this book retains both the accuracy and level of previous editions. In addition, the authors have maintained the previous emphasis on care and clarity in explanations, reasons that various techniques are used, and the inclusion of a large number of examples and exercises involving real (or realistic) business and economic data.
CHANGES IN THE FIFTH EDITION
Building on the foundation of historical rigor and careful discussion of statistical concepts from previous editions, the fifth edition includes computer applications and interpretation as integral tools in the decision-making process and realistic examples and exercises with an accompanying CD-ROM that includes data files for all computer based exercises.
Computer Integration
Previous editions of this book did not include computer applications. One new feature of the fifth edition is the integration of computer applications with emphasis on statistical thinking and interpretation. You will find coverage of the Minitab Statistical System, Microsoft Excel and its Data Analysis ToolPak, and two add-ins to Excel: PHStat2, and TreePlan.
Our students use the computer with great success. We see an increase in student comprehension, a more positive attitude toward statistical analysis, and improved oral and written presentations. By using these tools, students are discovering the "fun" of statistics.
Minitab and Excel
Computer applications are integrated throughout the text on a need-to-know basis. We do not emphasize "how" to use a particular software package, but rather concentrate on the interpretation of output leaving instructions to screen shots and callouts. Figure 8.12 and Figure 2.3 illustrate computer output from Minitab and Excel respectively. Suppose that a student wants to estimate the mean fuel consumption for a particular truck model. First, we develop an appropriate confidence interval. Then our approach turns to computer integration by obtaining Figure 8.12 with Minitab. Interpretation begins noting that no evidence of nonnormality exists (Anderson-Darling Normality Test). An icon in the margin with an arrow passing through the word INTREPRETATION indicates basic observations from the graph. Figure 2.3, an Excel output, provides a histogram of the weights of a random sample of 100 bottles of a particular suntan lotion.
If independent, random samples of 24 trucks are repeatedly selected from the population and confidence intervals for each of these samples are determined, then over a very large number of repeated trials, 90% of these intervals will contain the value of the true mean
Minitab 13.0 is used in this book. Academics and professionals respect the Minitab Statistical System for its power, ease-of-use, outstanding on-line help system, and excellent training opportunities. Minitab is widely used both in education and industry.
Most readers are already familiar with Microsoft Excel, the spreadsheet application from the Microsoft Office suite of programs. Keep in mind that Microsoft Excel is a spreadsheet package and not a statistical analysis package. The authors are well aware that many academics may question the use of Excel for statistical techniques. But many people wish to use Excel for some statistical analyses and in this book you will learn how and when to effectively use Excel. This text familiarizes students with Excel and the Data Analysis ToolPak, and discusses the positive features of Excel. Where appropriate, we also point out shortcomings in using Excel for statistical analysis purposes.
PHStat and TreePlan
The two add-ins to Microsoft Excel that are used in this book are PHStat2 and TreePlan. PHStat2 provides a custom menu of topics that supplement the Data Analysis Add-in Tools already included in Microsoft Excel. Between these two, the user is able to perform statistical analysis for most of the topics that would be covered in a business statistics course at the introductory level. TreePlan is useful with certain decision-making problems and is featured in Chapter 19 only.
Software and Data Files
PHStat2, TreePlan, and data files for both examples and exercises are included on a CD-ROM that accompanies this book.
Examples and Exercises
Examination of this book and the included CD-ROM reveals the importance that we place on working with real data. Problems that come to us in the business and economic world do not exactly fit the standard assumptions from mathematical statistics. Students need to learn how to interpret real problems and adapt them to standard models of analysis. In this way the great power of the standard analysis models can help you to unlock the important relationships contained in real processes and systems. Proper modeling, analyzing the data, and using the power of available computer procedures are the keys to understanding these important relationships. In this book you will see many examples of how statistical procedures are applied combined with discussions of why certain analyses were performed and how to interpret the results.
A small CD icon in the margin next to an example indicates that the data for that example is stored in the CD-ROM that accompanies this book. The name of the data file is below the CD. For example, you will see a CD with the name Suntan in the margin next to Example 2.1.
In Example 2.1 the operations manager at a suntan lotion manufacturing plant wants to be sure that the process for filling 8 oz (237 mL) bottles of a particular suntan lotion is operating properly. The file Suntan contains weights of a random sample of 100 bottles of this particular suntan lotion. Files are saved in Minitab (with extensions mtw and mtp) and in Excel (with extension .xls). Students open the file corresponding to the software package that they intend to use. Here, a student can choose between Suntan.mtw, Suntan.mtp or Suntan.xls.
End-of-Chapter Bibliographies/Web Sites
Many of the chapters include bibliographic references and/or suggested Web sites that provide students with additional sources for more advanced information.
CHAPTER SUMMARIES
CHAPTERS 1-3: DATA ANALYSIS WITH EMPHASIS ON DESCRIPTIVE STATISTICS
Chapters 1 through 3 provide a strong data analysis foundation. Here you will learn basic computational procedures and how to examine data using statistical and graphical tools. The emphasis here is description of the data and how you can develop appropriate intuition as you examine data. Chapter 1 provides a foundation in systems thinking-that helps us formulate problems. Chapter 2 provides extensive analysis procedures for single variables. Chapter 3 provides descriptive tools for beginning to explore the relationships between two variables -- clearly an important requirement for business and economics problems. You will note the extensive use of examples and will learn how many computer based graphical procedures can be used to help gain insights.
CHAPTERS 4-6: PROBABILITY AND RANDOM VARIABLES
Chapters 4 through 6 provide a rigorous foundation in probability and random variables. This material provides the foundation for important decision making and for statistical analysis. We have included material that goes beyond most textbooks including extensive applications using Bayes Theorem and over-involvement ratios. We show how to use the computer to obtain probabilities from standard distributions. We have included considerable discussion of joint random variables and linear combinations of independent and correlated random variables, to provide a foundation for applications in areas such as finance.
CHAPTERS 7-9: CLASSICAL STATISTICAL INFERENCE
Chapters 7 through 9 are a careful development of classical statistical inference that is basic to interpreting results and decision making. Sampling distributions are introduced and the central limit theorem is introduced using both practical discussion and Monte Carlo simulation. Confidence intervals and hypothesis tests are developed extensively for both single populations and comparisons between populations. You will learn the key modeling and analysis concepts and how to use the computer to perform the tedious calculations and to prepare clear displays of your results.
CHAPTERS 10-12: CORRELATION AND REGRESSION
Chapters 10 through 12 provide an extensive development of correlation and simple and multiple regression. In addition to development of both a clear understanding of regression analysis and its interpretation we have also included many important extensions such as transformations for non-linear models, dummy variables, lagged variables, effect of missing variables, time series data, and more. Many examples indicate how to interpret the various statistics. In addition there is discussion of the thinking required for developing regression models. An extended case example takes you through the various analysis procedures that would typically be used to develop a multiple regression model. This example illustrates how the computer can be used effectively in the model development process.
CHAPTER 13: NONPARAMETRIC STATISTICS
This chapter introduces the student to nonparametric statistics including the Sign Test, Wilcoxon Signed Rank Test, Mann-Whitney U Test, Wilcoxon Rank Sum Test, and the Spearman Rank Correlation. Confidence Intervals and computer applications are new in this edition.
CHAPTER 14: GOODNESS-OF-FIT TESTS AND CONTINGENCY TABLES
A test of the hypothesis that data are generated by a fully specified probability distribution is considered first. Next, we test the hypothesis that data are generated by some distribution, such as the binomial, the Poisson, or the normal, without assuming the parameters of that distribution to be known. The chi-square test can be extended to deal with a problem in which a sample is taken from a population, each of whose members can be uniquely cross classified according to a pair of attributes. Computer applications are included.
CHAPTER 15: ANALYSIS OF VARIANCE
Chapter 15 provides a good foundation for one-way and two-way analysis of variance. Clear computer based examples indicate how to implement the procedures.
CHAPTER 16: INTRODUCTION TO QUALITY
Control charts for means, standard deviations, proportions, number of occurrences, and ranges are included in this chapter. Process capabilities and computer applications are also discussed.
CHAPTER 17: TIME SERIES ANALYSIS AND FORECASTING
Chapter 17 provides an introduction to index numbers and to basic procedures for time series forecasting. With this chapter and the numerous examples you will be able to start developing some useful forecasting models.
CHAPTER 18: ADDITIONAL TOPICS IN SAMPLING
Students will study the basic steps of a sampling study, sampling and nonsampling errors, simple random sampling and stratified sampling, determination of sample size, and other sampling methods.
CHAPTER 19: STATISTICAL DECISION THEORY
Topics in this chapter include decision making under uncertainty, solutions not involving the specification of probabilities (maximin criterion and minimax regret criterion), expected monetary value, decision trees sampling information (Bayesian analysis and value), and allowing for risk (Utility Analysis). TreePlan and other computer applications are new to this edition.
SUPPLEMENT PACKAGE
This text is accompanied by many supplements for both students and instructors.
FOR THE STUDENT
Student Solutions Manual
A Student Solutions Manual, prepared by Steve Huchendorf, contains detailed solutions to all even-numbered exercises available with this text. These solutions provide feedback and allow you to check your answers to these exercises. The cycle of learning statistical procedures in depth followed by working with real problems followed by feedback on your solution has led to successful learning by thousands of students in our combined years of teaching statistics. Our teaching experience and shared discussion with many other strong teachers has provided the learning environment in this book that can also help you to be successful.
Companion Web Site
The Web site for this text found at www.prenhall.com/newbold includes: Interactive Study Guide, In the News articles, Internet Exercises, and the Instructor's Resources (password protected).
FOR THE INSTRUCTOR
Instructor's Solutions Manual
Prepared by Steve Huchendorf, the Instructor's Solutions Manual features detailed solutions and answers to all of the text exercises.
Test Item File
The test item file, prepared by Andrew Narwald of the University of San Diego, contains a variety of true/false, multiple choice, and essay questions for every chapter.
TestGen-EQ Software
New for this edition, the print Test Banks are designed for use with the TestGen-EQ test-generating software. This computerized package allows instructors to custom design, save and generate classroom tests. The test program permits instructors to edit, add, or delete questions from the test banks; edit existing graphics and create new graphics; analyze test results; and organize a database of tests and student results. This new software allows for greater flexibility and ease of use. It provides many options for organizing and displaying tests, along with a search and sort feature. The software can prepare 25 versions of a single test.
PowerPoint Presentations
Prepared by Mark Karscig of Central Missouri State University, the slides are oriented toward text learning objectives and build upon key concepts in the text. They are available for instructors to download from www.prenhall.com/newbold. They are also found on the Instructor's Resource CD-ROM.
Instructor's Resource CD-ROM
The Instructor's Resource CD-ROM provides the electronic files for the entire Instructor's Solutions Manual (in MS Word), PowerPoint presentations (in PowerPoint), Test Item File (in MS Word), and computerized test bank (TestGen-EQ).
WebCT, Blackboard, CourseCompass
Prentice Hall now makes its class-tested online course content available in WebCT, Blackboard, and CourseCompass. Instructors receive easy-to-use design templates, communication, testing, and course management tools. To learn more, contact your local Prentice Hall representative or go to http://www.prenhall.com/demo for a quick preview of our online solutions.
