Improving measureable external factors influence on construction project duration estimation

Abstract

The purpose of this study was to determine whether the use of building function variables as dummy variables affected the duration of construction projects, together with identified measureable external factors. Multivariate regression is a technique that estimates a single regression model with more than one outcome variable. When there is more than one predictor variable in a multivariate regression model, the model is a multivariate multiple regression. Goodness of Fit (R2) of the equation regression analysist used as sensibility benchmarks. Variables are transformed to index number for unit synchronize. If the result is unsatisfied for predicting a project duration, an implementation of dummy variables could be tried if there any improvement of R2. The trial on this research, 43 data show that in first stage, five influence factors: Education Index, Technology Absorption Index, Labor Experience Index, New Technology Availability Index, and Innovation Index generate regression equation without full fill the mathematical requirement. At the second stage, by adding dummy variables based on type of building, apartment, office, hotel and other then the three type together with the five external factors, afford a good R2.