建设工程造价外文翻译文献编辑.docx

建设工程造价外文翻译文献编辑.docx

《建设工程造价外文翻译文献编辑.docx》由会员分享，可在线阅读，更多相关《建设工程造价外文翻译文献编辑.docx（19页珍藏版）》请在冰点文库上搜索。

文献信息：

文献标题：

FactorsinfluencingaccuracyofconstructionprojectcostestimatesinPakistan:

Perceptionandreality（影响巴基斯坦建设工程造价估算准确性的感知因素和实际因素）

国外作者：

FarrukhArif，SaroshH.Lodi，NidaAzhar

文献出处：

《InternationalJournalofConstructionManagement》,2015,15

（1）:

59-70

字数统计：

英文3023单词，17564字符；中文5181汉字

外文文献：

FactorsinfluencingaccuracyofconstructionprojectcostestimatesinPakistan:

Perceptionandreality

AbstractConstructionprojectsareuniqueastheyarepricedbeforebeing

constructed.Therefore,accuracyofconstructionprojectcostestimatesispivotalinprojectsuccess.Severalstudieshavedeterminedfactorsinfluencingtheaccuracyofcostestimates.Comparativelylessinformationisavailableforconstructionindustriesindevelopingcountries.ThisstudyidentifiedfactorsinfluencingtheaccuracyofcostestimatesforconstructionprojectsinPakistan.Costdatawascollectedfor46completedconstructionprojects.Fourdimensions60factorswereconsidered.Dimensionsincluded:

projectcharacteristics,projectteam,estimatingprocedures,and（costingrelated）informationitems.Arigorousanalysisframeworkbasedonprincipalcomponentanalysisandregressionanalysiswasused.Involvementofthecontractorintheestimationprocedureandlabourrateswerefoundtobethemostsignificantfactors.Earlyinvolvementofthecontractorcanresultinrealisticestimatesthroughtimelyinputfromsubcontractors,materialssuppliersandmanufacturersamongothers.ThisalsohelpsincontrollinglabourcostsasmostoftheconstructionprojectsinPakistanemploylabourthroughsubcontractors.

Keywords:

costestimates;Pakistan;factorsinfluencingaccuracy;estimatebias;estimateconsistency;principalcomponentanalysis;regressionanalysis

Introduction

Theconstructionindustryisuniqueinitsworkingascomparedtoothermanufacturingandproductdevelopmentindustries.Sinceitisaproject-basedactivity,everyconstructionprojecthasitsownnature,requirements,andcharacteristics.Theuniquenessofconstructionprojectsisthattheyarepricedbeforebeingconstructed.

Therefore,accuracyofprojectestimateshaveapivotalrole.Thisisthereasonthatmoreoftenthannot,comparisonofactualcosttoearlycostestimatesbecomesthemeasureoftheprojectteam,performanceandoverallsuccessoftheproject（Oberlender&Trost2001）.Pricingandtheprofitrequiredfromtheconstructionprojectaredecidedatthetimeofbiddingandthebid’sacceptance（Halpin&Senior2009）.Therefore,constructionprojectmanagersareprimarilyinvolvedincostcontrol.Thismakesitnecessaryforconstructionmanagerstounderstanddifferentfactorsthatinfluencetheaccuracyofprojectcostestimates.Severalresearchershaveconducteddetailedstudiesinordertodeterminefactorsinfluencingtheaccuracyofcostestimates.However,comparativelylessinformationonthisisavailablefortheconstructionindustriesindevelopingcountries.Realizingthisneed,thepaperpresentsarigorousanalysistodeterminefactorsinfluencingtheaccuracyofconstructioncostestimates.Thedatawascollectedfrom46constructionprojectsinPakistan.Theauthorsadoptedatwo-stagestatisticalanalysisframeworktodeterminetheperceivedandrealfactorsinfluencingtheaccuracyofestimatesofconstructionprojectcosts.Certainconclusionshavebeendrawnandstrategic-levelrecommendationsareprovided,basedonresultsoftheanalysis,toimprovethecostestimationprocessandtoreduceinaccuracyintheconstructionindustryofPakistan.

Thestudypresentedinthispaperfirstprovidesabriefsynopsisofsimilarpriorstudiesconductedfromdifferentperspectives.Thenitprovidesanaccountoftheresearchobjectivesandscope,followedbydetailsonresearchmethodologyanddatacollection.Themainpartofthepaperprovidesdetailsofthedataanalysisandits

results.Thisisfollowedbydiscussionofresultsoftheanalysis.Finally,strategic-levelrecommendationsareprovidedfortheimprovementofcostestimationpracticesintheconstructionindustryofPakistanwhichcouldbeequallyapplicableforotherdevelopingconstructionindustries.

Priorstudies

Severalstudieshavebeenconductedrelatedtoaccuracyofcostestimatesforconstructionprojects.Onmanyoccasions,researchershaveattemptedtomeasuretheimpactofcertainprojectcharacteristicsontheaccuracyofestimates（Skitmore1988;Akintoye&Fitzgerald2000）.Akintoye（2000）conductedastudytoidentifyandunderstandthefactorsthatinfluencecontractors’costestimationpracticesintheUK.Itwasconcludedthatthemainfactorsinfluencingcostestimatingpracticesincludedthecomplexityoftheproject,thescaleandscopeoftheconstruction,marketconditions,themethodofconstruction,siteconstraintsandlocation.AibinuandPasco（2008）conductedastudytoexploretheaccuracyofpre-tenderbuildingcostestimatesinAustralia.Theyidentifiedeightprojectcharacteristicsandconductedanalysisusingmultipleregressionanalysis;theyfoundthattheaccuracyofestimatesisinfluencedbyprojectsize.

Ontheotherhand,certainotherstudieshadnotonlyaccountedforprojectcharacteristicsbutalsootheraspects,suchasprojectteam-relatedfactors,estimatingprocedures,and（costingrelated）informationitems.Carr（1989）conductedastudytodefinethebasicrequirementsfordevelopingreliableestimates.Heconcludedthattheaccuracyoftheestimatedependsontheestimator’sabilitytoseetheprojectfro mamacroperspective,hisexperienceandjudgementskills.Ashwarth（1994）concludedthatavailabilityofinformationonthedesign,typeandqualityofcost data,typeofproject,projectsize,numberofbiddersoncompetitiveprojects,stabilityofmarketconditions,personalfactors,proficiencyinestimating,andsheerquantitativeexperienceinfluencetheaccuracyofestimatingthecostsofconstructionwork.OberlenderandTrost（2001）developedanestimatescoringsystemandconsequentlysoftwaretomeasuretheaccuracyofestimates.Theyfoundthattheaccuracyofan

earlyestimatehasfourdeterminants:

‘

（1）whowasinvolvedinpreparingtheestimate;

（2）howtheestimatewasprepared;（3）whatwasknownabouttheproject;and（4）otherfactorsconsideredwhilepreparingtheestimate’.TrostandOberlender（2003）conductedfactoranalysisandmultivariateregressionanalysistodetermineasuitablemodelforpredictingtheaccuracyofestimates.Theyidentifiedfivefactorsthatweresignificantinpredictingaccuracy.Thesefactorsincluded:

basicprocessdesign,teamexperienceandcostinformation,timeallowedtopreparetheestimate,siterequirements,andbiddingandlabourclimate.Enshassietal.（2010）identifiedfactorssuchassupplyofrawmaterialsandequipment,andfluctuationsinthecostofbuildingmaterialsasinfluencingcostoverruns.

Thestudypresentedinthispaperconsideredallfourdimensionsofthefactorsinfluencingtheaccuracyofcostestimates:

i.e.factorsrelatedtoprojectcharacteristics,theprojectteam,estimatingprocedures,andinformationontheproject.

Researchobjectivesandscope

TheprimeobjectiveofthisresearchwastoidentifythefactorsthatinfluencetheaccuracyofconstructionprojectcostestimatesinPakistan.Forthispurposeitwasdeemednecessarytoapproachthestudyfromtwomajorperspectives:

（1）thefactorsthatareperceivedtobeinfluencingtheaccuracyand

（2）thefactorsthatdidinrealityinfluencetheaccuracyofcostestimateswhenanalysedusingtheactualcostbiasintheprojectdata.

Researchmethodologyanddatacollection

Athoroughliteraturereviewwasperformedtoidentifythekeyelementsthatmayprovideagoodmeansofjudgingtheaccuracyofcostestimates.Theliteraturereviewwasdonethroughbooks,conferenceproceedings,theinternet,and leadingconstructionmanagementandengineeringjournals.Followingtheidentificationofthekeyelementsofthesurvey,someunstructuredexpertinterviewswereconductedtoverifythekeyelementsaswellasidentifyanyfurtherelementsrelevanttothepracticesandissuesforestimatingcostsinthelocalconstructionindustry.

AstructuredquestionnaireconsistingoftwopartswasdesignedpartsAandB.PartArequestedtherespondent’spersonalinformation（e.g.workexperience,experienceascostestimator,etc.）andcompanyinformation（e.g.typeoforganization,typesofconstructionworkperformed,yearsinbusiness,annualvolumeofwork,numberofpermanentemployees,citiesofoperation,etc.）.PartBrequestedinformationonprojectcosts（e.g.projectname,type,client,estimatedprojectcost,totalprojectcost,estimatedprofitmargin,etc.）.

Furthermore,alistof60factorscategorizedunderfourdimensionswasprovidedtotherespondents.TherespondentswereaskedtoratetheinfluenceofeachfactorontheaccuracyofthecostestimateoftheprojectforwhichcostinformationwasprovidedonaLikertscaleof1（leastinfluential）to5（mostinfluential）.ThesedimensionsincludedProjectTeam（PT）having16factors,ProjectCharacteristics（PC）having19factors,EstimatingProcedures（EP）having14factorsand（costingrelated）InformationItems（Info）having11factors.ThedimensionsandfactorsarelistedinTable1.

Table1.Factorsinfluencingaccuracy

ProjectTeamrelatedfactors ProjectCharacteristicsrelatedfactors

PT1Owner’sclient’sexperienceoftheconstructiontypePT2Financialstatusofclient

PT3Impactoftypeofclient

PT4LevelofinvolvementofclientintheestimationprocedurePT5Willingnesstoinvestmentinproject

PT6Noofotherprojectsofclient

PT7LevelofinvolvementofdesignerintheestimationprocedurePT8Levelofexpertise