Bayes Linear Statistics Established by WALTER A. SHEWHART and SAMUEL S. WILKS Bayes Linear Statistics Theory and Methods Michael Goldstein and David Wooff DurhamUniversity,UK Copyright2007 JohnWiley&SonsLtd,TheAtrium,SouthernGate,Chichester, WestSussexPO198SQ,England Telephone(+44)1243779777 Email(forordersandcustomerserviceenquiries):[email protected] VisitourHomePageonwww.wileyeurope.comorwww.wiley.com AllRightsReserved.Nopartofthispublicationmaybereproduced,storedinaretrievalsystemor transmittedinanyformorbyanymeans,electronic,mechanical,photocopying,recording,scanning orotherwise,exceptunderthetermsoftheCopyright,DesignsandPatentsAct1988orunderthe termsofalicenceissuedbytheCopyrightLicensingAgencyLtd,90TottenhamCourtRoad,London W1T4LP,UK,withoutthepermissioninwritingofthePublisher.RequeststothePublishershould beaddressedtothePermissionsDepartment,JohnWiley&SonsLtd,TheAtrium,SouthernGate, Chichester,WestSussexPO198SQ,England,[email protected],orfaxedto(+44) 1243770620. 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Val,Ben,Dad,andmymotherMary Contents Preface xvii 1 The Bayes linear approach 1 1.1 Combining beliefs with data . . . . . . . . . . . . . . . . . . . . 2 1.2 The Bayesian approach . . . . . . . . . . . . . . . . . . . . . . . 3 1.3 Features of the Bayes linear approach . . . . . . . . . . . . . . . 6 1.4 Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1.4.1 Expectation, variance, and standardization . . . . . . . . 8 1.4.2 Prior inputs . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.4.3 Adjusted expectations . . . . . . . . . . . . . . . . . . . 9 1.4.4 Adjusted versions . . . . . . . . . . . . . . . . . . . . . 10 1.4.5 Adjusted variances . . . . . . . . . . . . . . . . . . . . . 10 1.4.6 Checking data inputs . . . . . . . . . . . . . . . . . . . . 11 1.4.7 Observed adjusted expectations . . . . . . . . . . . . . . 12 1.4.8 Diagnostics for adjusted beliefs . . . . . . . . . . . . . . 12 1.4.9 Further diagnostics for the adjusted versions . . . . . . . 12 1.4.10 Summary of basic adjustment . . . . . . . . . . . . . . . 13 1.4.11 Diagnostics for collections . . . . . . . . . . . . . . . . . 14 1.4.12 Exploring collections of beliefs via canonical structure . 17 1.4.13 Modifying the original specifications . . . . . . . . . . . 19 1.4.14 Repeating the analysis for the revised model . . . . . . . 20 1.4.15 Global analysis of collections of observations . . . . . . 22 1.4.16 Partial adjustments . . . . . . . . . . . . . . . . . . . . . 24 1.4.17 Partial diagnostics . . . . . . . . . . . . . . . . . . . . . 27 1.4.18 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . 29 1.5 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 2 Expectation 33 2.1 Expectation as a primitive. . . . . . . . . . . . . . . . . . . . . . 33 2.2 Discussion: expectation as a primitive . . . . . . . . . . . . . . . 35 2.3 Quantifying collections of uncertainties . . . . . . . . . . . . . . 37 2.4 Specifying prior beliefs . . . . . . . . . . . . . . . . . . . . . . . 39 2.4.1 Example: oral glucose tolerance test . . . . . . . . . . . 39