Accurate client budget estimates are critical to the initial decision-to-build process for the highway construction projects. This decision-to-build point in a project's development is seen as the international standard for measuring any subsequent cost estimate inaccuracies involved (National Audit Office/Department of Transport, 1992; World Bank, 1994; Nijkamp and Ubbels, 1999), with accuracy being defined as the difference between the initial project estimate at the decision-to-build stage and the real, accounted project cost determined at the time of project completion. Expressed as a percentage of estimated cost, this is often termed cost escalation, cost overrun or cost growth, and occurs as a result of many factors, some of which are related to each other, but all are associated with forms of risks. The analysis of these risks is often a necessary step for the improvement of any given estimating system and can be used to diagnose trouble spots and to pinpoint areas where project estimating accuracy improvement might be obtained. In this research, highway projects in Queensland, Australia that have suffered significant cost overrun are analysed. The research seeks to address the gap in the knowledgebase as to why highway projects overrun their costs. It focuses on understanding how client projects budgets go wrong, when dealing with project risk. The foundation for this research is drawn from the post-mortem analysis of highway projects, each costing in excess of A$1m and whose final total expenditure exceeded budget by 10% or greater. The research identifies client risk variables which have contributed to significant cost overrun and then uses factor analysis and also expert elicitation, using nominal group technique, to establish groups of importance ranked client risks. Stepwise multivariate regression analysis is then used to investigate any correlation of these risks, along with project attributes such as highway project type, indexed project cost, geographic location and project delivery method to the percentage of cost overrun. The research results indicates a correlation between the reciprocal of project budget size and percentage cost overrun that can be useful in clients determining more realistic decision-to build highway budget estimates when taking into account project size in relation to economy of scale.

The prime objective of this thesis is to research and develop a new system of project budgeting, monitoring and forecasting to meet the needs of the Construction Industry. It is intended that this work will facilitate the means for more efficient control of projects from inception to final completion, utilising where possible the latest developments in computer technology. The initial stage of the work involves an investigation and appraisal of existing methods of formulating project budgets. In particular attention is paid to previous work in the development of mathematical 's' curve models, together with their limitations in use and application. Potential for future development is also identified. The thesis then focuses on the evolution of an improved modelling philosophy for project budgets and forecasts which overcomes previously known problems. In parallel with this work is the development of a computerised system intended to enable the testing of the model against live project data. The model finally selected is then tested against the extensive research work previously undertaken by the DHSS and the data collected from sixteen construction projects. To facilitate the development of a suitable control system to act as a vehicle for the application of the principles developed, a contextual survey is included. This survey is intended to provide an update of previous survey work undertaken by the author in 1977 and to further investigate factors orientated specifically to the objectives of the thesis. The research then concentrates on the development of an integrated set of sub-systems which contribute to the budgeting, monitoring and prediction of project expenditure. These systems are developed in accordance with the need to establish the financial status of projects both before, during and after they are completed. The overall system is based on the latest computer technology available and is designed to be flexible in its application. Tests documented in the text prove that the system operates both in principle and in practice. A further extension of the research is the use of the various project data bases to provide information for a corporate control system which has been developed in principle. This thesis provides a significant step forward in computerised project budgeting and control utilisng 's' curve philosophy and provides a basis for further development. Potential exists for future development of the prediction and corporate control systems, together with software developments to improve general application over a wide range of industries and disciplines where project work is undertaken.

Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: This study examined the origins and development of theory-based evaluation (TBE) and the logic models associated with this approach. This was done in order to better understand the roots and evolution of these models which are currently used by donor agencies both nationally and internationally. It was found that logic models, which are used for both project management and evaluation, had their origins in a range of domains including management, education and curriculum design from as early as 1909. Early evaluators from the education, training and health sectors as well as contextual factors such as the professionalization of evaluation and an ever- increasing demand for accountability contributed significantly to the development of both TBE and its associated models. A systematic review of a large sample of logic models and logical frameworks was conducted in order to bring some order and clarity to the plethora of models facing stakeholders in the field of evaluation. It was discovered that four key types of logic models and two key types of logframes face developers and users of models but that the "branding" of donors of their particular demand for accountability, obscures this fact. In order to understand the experience of South African Non-Governmental Organisations when engaging with donors and their demands for accountability a survey was carried out of those organisations which were utilising a specialised form of planning tool. The findings of this study show that South African donors, like their international counterparts, mainly use the models associated with TBE to obtain standardised and focused evidence of results from projects albeit with a distinct scepticism about the actual necessity of some of the donor requirements. Most Non-Governmental Organisations view the donor requirements, such as the logic model and logical framework, as necessary in the funding relationship despite indicating that they find the models inflexible. The study not only makes a contribution to an under-researched area in programme evaluation, it also provides insights into an under-researched area of the South African Non-Governmental sector. / AFRIKAANSE OPSOMMING: Die doel van die studie was om 'n in-diepte begrip van die ontwikkeling van logika modelle ("logic models") en logika raamwerke ("logical framework") te ontwikkel ten einde die ervarings van Suid-Afrikaans nie-regeringsorganisasies met donateurs beter te begryp. In besonder was die doel om vas te stel hoe sodanige organisasies die vereistes rondom projekbeplanning, monitering, evaluasie en rapportering ervaar. Die studie het gevind dat die oorspronge van hierdie modelle, wat beide vir projekbestuur en evaluasie gebruik word, te vinde is in verskeie areas insluit bestuur, opvoedkunde and kurrikulumontwerp. Die eerste generasie evalueerders in opvoedkunde, opleiding en gesondheid sowel as kontekstuele faktore soos die professionalisering van evaluasie en die immer-toenemende vereistes van rekenpligtigheid het alles beduidend bygedra tot die ontwikkeling van logika modelle. 'n Sistematiese oorsig en ontleding van 'n beduidende steekproef van logika modelle en raamwerke is uitgevoer ten einde meer helderheid en sistematiek te kry in 'n domein waar daar uiteenlopende benaderings en modelle is. Daar is gevind dat vier sleuteltipes logika modelle en twee sleuteltipes logika raamwerke deur die meeste organisasies gebruik word maar dat verskillende befondsingsagentskappe en organisasies hul eie betekenis en inhoud aan hul logika modelle gee. Ten einde die ervarings van Suid-Afrikaanse nie-regerings organisasies te begryp is 'n opname uitgestuur aan alle organisasies wat hierdie raamwerke gebruik. Die resultate van die opname wys dat Suid-Afrikaanse befondsagentskappe, soos hulle internasionele vennote, veral modelle gebruik wat geasosieer is met teorie-gebaseerde evaluasie ten einde gestandaardiseerde en gefokusde getuienis van projektesultate te genereer. Die meerderheid Suid-Afrikaanse nie-regeringsorganisasies aanvaar die vereistes van donateurs alhoewel hierdie "aanvaarding" gepaardgaan met 'n duidelike skeptisisme oor die absolute noodsaaklikheid van somige van hierdie vereistes. Die meerderheid organisasies beskou donateur vereistes, veral wat betref die logika model en die logika raamwerk, as noodsaaklik binne die konteks van die befondsingsverhouding ten spyte van persepsies dat sodanige modelle some uiters rigied kan wees. Die studies maak 'n bydrae, nie alleen in area in programevaluasie waar daar weinig navorsing is nie, maar dit bied ook insig in die gedrag en persepsies van die Suid-Afrikaanse nie-regeringsektor wat programevaluasie praktyke betref.