Timing of Major Transportation Investments

摘要

This report offers a broad overview of timing research as it applies to majortransportation investments. Specific emphasis is given to major public transit investments. The report is designed to provide planners and decision-makers with a better understanding of timing research. The report emphasizes basic economic principles of investment timing rather than detailed techniques. The purpose of this particular report is to describe the kind of investment timing rules most useful in making investment decisions so that transportation investments are made most efficiently. The report is divided into nine chapters. Chapter 1 is an introduction. Chapter 2 reviews basic concepts related to economic analysis of investment timing. Chapter 3 discusses the perceptions and attitudes of the planning profession toward investment timing. Chapter 4 shows with examples both quantitative and qualitative significance of timing. Chapter 5 describes conditions under which waiting can create a value to invest. Chapter 6 discusses timing rules under different scenarios, including traditional rules, rules with certainty, and rules with uncertainty. Chapter 7 presents two approaches to time subsequent analysis of a project following an intial build-later decision. Chapter 8 identifies what type of data economic principles require, what federal regulations on investment analysis require, and what is inadequate in current practice. Chapter 9 provides a number of recommendations regarding what needs to be done in order to use these economic priniciples of investment timing in practice. References are included along with a technical appendix on models of investment timing.