Ron C. Mittelhammer Mathematical Statistics for Economics and Business Second Edition Mathematical Statistics for Economics and Business Second Edition Ron C. Mittelhammer Mathematical Statistics for Economics and Business Second Edition With 93 Illustrations RonC.Mittelhammer SchoolofEconomicSciences WashingtonStateUniversity Pullman,Washington USA ISBN978-1-4614-5021-4 ISBN978-1-4614-5022-1(eBook) DOI10.1007/978-1-4614-5022-1 SpringerNewYorkHeidelbergDordrechtLondon LibraryofCongressControlNumber:2012950028 #SpringerScience+BusinessMediaNewYork2013 Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeorpart ofthematerialisconcerned,specificallytherightsoftranslation,reprinting,reuseofillustrations, recitation,broadcasting,reproductiononmicrofilmsorinanyotherphysicalway,andtransmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodologynowknownorhereafterdeveloped.Exemptedfromthislegalreservation arebriefexcerptsinconnectionwithreviewsorscholarlyanalysisormaterialsuppliedspecifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaserofthework.Duplicationofthispublicationorpartsthereofispermittedonlyunderthe provisionsoftheCopyrightLawofthePublisher’slocation,initscurrentversion,andpermissionfor usemustalwaysbeobtainedfromSpringer.PermissionsforusemaybeobtainedthroughRightsLink at the Copyright Clearance Center. 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Printedonacid-freepaper SpringerispartofSpringerScience+BusinessMedia(www.springer.com) To my wife Linda, and to the memory of Carl, Edith, Dolly, and Ralph. n Preface to the Second Edition of Mathematical Statistics for Economics and Business n n ThegeneralobjectivesofthesecondeditionofMathemat- icalStatisticsforEconomicsandBusinessremainthesameasthefirst,namely, to provide a rigorous and accessible foundation in the principles of probability and in statistical estimation and inference concepts for beginning graduate students and advanced undergraduate students studying primarily in the fields ofeconomicsandbusiness.Sinceitspublication,thefirsteditionofthebookhas foundusebythosefromotherdisciplinesaswell,includingthesocialsciences (e.g., psychology and sociology), applied mathematics, and statistics, even though many of the applied examples in later chapters have a decidedly “eco- nomicsandbusiness”feel(althoughtheexamplesarechoseninsuchawaythat theyarefairlywell“self-contained”andunderstandableforthosewhohavenot studiedeitherdisciplineinsubstantialdetail). The general philosophy regarding how and why the book was originally written was presented in the preface to the first edition and in large measure couldbeinsertedatthispointfor motivatingthefundamentalrationaleforthe second edition. This philosophy includes the necessity of having a conceptual base of probability and statistical theory to be able to fully understand the application and interpretation of applied econometric and business statistics methods, coupled with the need to have a treatment of the subject that, while rigorous, also assumes an accessible level of prerequisites that can be expected to have been met by a large majority of graduate students entering the fields. The choice of topic coverage is also deliberate and decidedly chosen to form the fundamental foundation on which econometric and business statistics methodology is built. With the ongoing expansion, in both scope and depth, viii PrefacetotheSecondEditionofMathematicalStatisticsforEconomicsandBusiness of econometric and statistical methodology for quantitative analyses in both economics and business, it has never been more important, and many are now thinking absolutely essential, that a base of formal probability and statistics understandingbecomepartofstudenttrainingtoenableeffectivereadingofthe literatureandsuccessinthefields. Regarding the nature of the updates and revisions that have been made in producing the second edition, many of the basic probability and statistical concepts remain in common with the first edition. The fundamental base of probability and statistics principles needed for later study of econometrics, business statistics, and a myriad of stochastic applications of economic and business theory largely intersects the topics covered in the first edition. While a few topics were deleted in the second edition as being less central to that foundation, many more have been added. These include the following: greater detailontheissueofparametric,semiparametric,andnonparametricmodels;an introduction to nonlinear least squares methods; Stieltjes integration has been added strategically in some contexts where continuous and discrete random variable properties could be clearly and efficiently motivated in parallel; addi- tional testing methodology for the ubiquitous normality assumption; clearer differentiationofparametric andsemiparametrictestingofhypotheses;aswell as many other refinements in topic coverage appropriate for applications in economicsandbusiness. Perhaps the most important revision of the text has been in terms of the organization, exposition, and overall usability of the material. Reacting to the feedback of a host of professors, instructors, and individual readers of the first edition,thepresentationofboththepreviousandnewmaterialhasbeennotably reorganizedandrewrittentomakethetexteasiertostudyandteachfrom.Atthe highest level, the compartmentalization of topics is now better and easier to navigatethrough.Alltheoremsandexamplesarenowtitledtoprovideabetter foreshadowing of the content of the results and/or the nature of what is being illustrated.Sometopicshavebeenreorderedtoimprovetheflowofreadingand understanding(i.e.,therelativelymoreesotericconceptofeventsthatcannotbe assignedprobabilityconsistentlyhasbeenmovedtotheendofachapterandthe review of elements of real analysis has been moved from the beginning of the asymptotic theory chapter to the appendix of the book), and in some cases, selected proofs of theorems that were essentially pure mathematics and that did little to bolster the understanding of statistical concepts were moved to chapter appendices to improve readability of the chapter text. A large number ofnewandexpandedexercises/problemshavebeenaddedtothechapters. Whileanumberoftextsfocusedonstatisticalfoundationsofestimationand inferenceareavailable,MathematicalStatisticsforEconomicsandBusinessisa textwhoselevelofpresentation,assumedprerequisites,examplesandproblems, andtopiccoveragewillcontinuetoprovideasolidfoundationforfuturestudyof econometrics,businessstatistics,andgeneralstochasticeconomicandbusiness theory and application. Withits redesigned topic organization, additionaltopic coverage,revisionofexposition,expandedsetofproblems,andcontinuedfocus onaccessibilityandmotivation,thebookwillprovideaconceptualfoundation PrefacetotheSecondEditionofMathematicalStatisticsforEconomicsandBusiness ix on which students can base their future study and understanding of rigorous econometric and statistical applications, and it can also serve as an accessible refresher for practicing professionalswho wish to reestablish their understand- ing of the foundations on which all of econometrics, business statistics, and stochasticeconomicandbusinesstheoryarebased. Acknowledgments Inadditiontoalloftheacknowledgmentspresentedinthe firstedition,whichcertainlyremaindeservingofinclusionhere,Iwouldliketo thank Ms. Danielle Engelhardt, whose enormous skills in typing, formatting, andproof-checkingofthetextmaterialandwhosealwayscheerfulandpositive “can-do”personalitymadetherevision experienceamuch moreenjoyableand efficientprocess.IamalsoindebtedtoDr.MiguelHenry-Osorioforproofreading every character of every page of material and pointing out corrections, in addi- tion to making some expositional suggestions that were very helpful to the revisionprocess.Mr.SherzodAkhundjanovalsoprovidedexpertproof-checking, for which I am very grateful. I also thank Haylee and Hanna Gecas for their constant monitoring of my progress on the book revision and for making sure that I did not stray too far from the targeted timeline for the effort. I also wishtothankmycolleagueDr.TomMarsh,whoutilizedthefirsteditionofthis book for many years in the teaching of his econometrics classes and who providedmewithhelpfulfeedbackonstudentlearningfromandtopiccoverage in the book. Finally, a deep thank you for the many comments and helpful suggestions I continued to receive over the years from my many doctoral students, the students who attended my statistics and econometrics classes hereattheuniversity;themanyadditionalquestionsandcommentsIreceived from students elsewhere; and the input received from a host of individuals all overtheworld–therevisionofthebookhasbenefittedsubstantiallyfromyour input.Thankyouall.