Essays on the delivery of public infrastructure projects: Empirical analyses on transportation projects in Florida

A common goal of two essays in this dissertation is seeking to answer the question how to enhance performance of public-sector infrastructure projects. The first essay focuses on project control after the outset of a project. Based on production theories, construction process is interpreted in terms of managerial principles, and the following two questions are sought to be answered: 1) whether or not the nature of a change is significantly associated with cost performance; and 2) whether or not the adverse effect of a change on cost performance is amplified as the timing of its occurrence gets delayed. Analyses using data on roads, bridges, and traffic operations projects in Florida suggest that cost increase is attributable to the incompleteness in planning. In particular, a negative effect of owner-directed changes, e.g., plan modifications and changes resulting from engineering decisions, on cost performance, implies a potential advantage of extra effort in upfront engineering. In contrast, changes required to adopt efficiency-enhancing practices, e.g., partnering and value engineering, have a positive effect on cost performance. This suggests potential benefits that Design/Build delivery method may bring about through flexibility in coordination among project parties. Meanwhile, I observe only changes induced by natural environmental conditions to be time-sensitive, again emphasizing the importance of geotechnical engineering in project planning. Inspired by some disagreements in previous studies as well as by the results from the first essay, the second essay attempts to tackle public perception regarding putative advantages of Design-Build (DB), over the traditional project delivery method, Design-Bid-Build (DBB). In doing so, I seek to answer the following three questions: 1) for what type of project a public owner is likely to employ one method or the other; 2) to whom a public owner tends to award each type of project; and 3) to what degree owner's decisions yield varying consequences under the two methods in terms of project cost and schedule. Economic theories suggest that DB fits better with a large and environmentally uncertain project, thereby, requiring a better-qualified contractor (Bajari, McMillan, & Tadelis, 2009). However, the analyses of transportation projects in Florida over the last decade show that large and environmentally uncertain projects were not always delivered by DB especially for those assumed to have high impacts on road users or surroundings. Also, DB contractors having demonstrated histories of successful collaborations with the owner did not necessarily grab high chances of winning projects in the future. Regardless, the use of DB seems advantageous to schedule control while cost advantages of one over the other not being supported in this essay. These findings together call for further studies on how to enhance various benefits inherent in each delivery method.