A methodology for making construction productivity comparisons

This study provides a methodology for comparing productivity of different construction projects. A project level of analysis is presented as the best framework for analyzing construction productivity. The methodology applies fundamental concepts of productivity measurement at the firm level to a project environment. The major distinction for a project is the assumption of a time-labor trade off instead of the traditional capital-labor trade off. Nuclear power construction projects provide an example for the methodology. Due to the difficulty of measuring project duration, peak manning levels are used as a proxy for time. The results provide evidence of the relationship between project manning levels and productivity as well as such factors as the type of nuclear reactor, the mid-date of construction duration, and various measures of construction complexity. This study provides a methodology by which projects of a similar type can be compared. Construction productivity is difficult to measure due to a lack of standards for what constitutes construction inputs and outputs. There are a variety of construction products and a large number of construction operations. This has led to uncertainty regarding the published rates of productivity in the construction industry and in other industries. The methodology can be applied when the stated assumptions regarding capital and labor can be met. The methodology is useful for comparing final performance of project management at different sites and at different times. Two types of comparisons are discussed. The first assumes the absence of stochastic noise and uses the "best" project performance as the "frontier". The second type of comparison accepts the existence of noise and is simply the actual project productivity versus the productivity predicted by the regression equations. The method of comparison depends on the purpose of the analyst.