Forecasting the Final Cost of Iraqi Public School Projects Using Regression Analysis

Abstract

The actual final cost of public school building projects, like other construction projects, is unknown to the owner till the final account statement is prepared. An attempt to predict the final cost of such projects before work starts, using backward elimination regression analysis technique is carried out. The study covers two story (12 classes) school projects awarded by the lowest bid system. Records of (65) school projects completed during (2007-2012) are employed to develop and verify the regression model. Based on experts ‘convictions, nine factors are considered to have the most significant impact on the final cost. Hence they are used as model input parameters. These factors are; awarded bid price, average bid price, estimated cost, contractor rank, resident engineer experience, project location, number of bidders, year of contracting, and contractual project duration. It was found that the developed regression model have the ability to predict the final cost (FC) for school projects, as an output, with a very good accuracy having a correlation coefficient (R) of (93%), determination coefficient (R2)of(86.5%)and average accuracy percentage of(92.02%).