The Predictive Ability of Bromilow’s Time-Cost Model
Ng, S. Thomas, Mak, Michael M. Y., Skitmore, Martin, Lam, Ka Chi Lam, & Varnam, Mark (2001) The Predictive Ability of Bromilow’s Time-Cost Model. Construction Management and Economics, 19(2), pp. 165-173.
Bromilow’s log-log time-cost (BTC) model is tested and refitted with a new set of data for Australian construction projects completed between 1991 and 1998. It is shown that, as anticipated by earlier research, different parameter estimates are needed for different project types with smaller industrial projects taking less time to complete than the smaller educational and residential projects. This results in the development of two separate models – one for industrial projects (Ind) and one for non-industrial projects (Xind). No changes in parameter estimates are needed for projects with different client sectors, contractor selection methods and contractual arrangements. Alternatives to the log-log model failed to produce any improved fit. Finally, the results are compared with previous work to indicate the extent of changes in time-cost relationships in Australian construction projects over the last 40 years. This indicates a clear improvement in construction speed over the period. Furthermore, the "public" sector group in particular has exhibited a greater variation (up to 132%) over the years.
Impact and interest:
Citation counts are sourced monthly from and citation databases.
These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.
Citations counts from theindexing service can be viewed at the linked Google Scholar™ search.
Full-text downloads displays the total number of times this work’s files (e.g., a PDF) have been downloaded from QUT ePrints as well as the number of downloads in the previous 365 days. The count includes downloads for all files if a work has more than one.
|Item Type:||Journal Article|
|Keywords:||Cost, time, duration, time, cost, Bromilow model, linear regression, speed, productivity|
|Subjects:||Australian and New Zealand Standard Research Classification > BUILT ENVIRONMENT AND DESIGN (120000) > BUILDING (120200) > Quantity Surveying (120203)
Australian and New Zealand Standard Research Classification > BUILT ENVIRONMENT AND DESIGN (120000) > BUILDING (120200) > Building Construction Management and Project Planning (120201)
|Divisions:||Past > QUT Faculties & Divisions > Faculty of Built Environment and Engineering|
|Copyright Owner:||Copyright 2001 Taylor & Francis|
|Copyright Statement:||First published in Construction Management and Economics 19(2):pp. 165-173.|
|Deposited On:||13 Sep 2007 00:00|
|Last Modified:||10 Aug 2011 15:51|
Repository Staff Only: item control page