Identifying the factors affecting conceptual cost estimation of construction projects in volatile economies

The construction industry plays a vital role in the country's economy. Increasing the success rate of construction projects has become more important, especially, in volatile countries. For that matter, conceptual cost estimation is used from the very first point of the project, when the feasibility study is done. After that, when more detailed information is available, more accurate cost estimation is done with the help of the project design. In countries with volatile economies, predicting project costs beforehand is challenging due to economic fluctuations, resulting in more uncertainties when starting a construction project. Accurate conceptual cost estimation can help project owners overcome cost overruns and face economic instabilities. This study proposes a method for conceptual cost estimation for construction projects using historical data analysis as the foundation for creating a connection between the primary factors influencing the cost of building projects to produce estimations for new projects in Turkey. The goal of construction conceptual cost estimation is to predict the cost of a construction project, including all temporary expenditures generated throughout the construction process, and to serve as a basis for budgeting, planning, and decision-making. This paper uses quantitative data analysis methods such as Neural Network, Decision Trees, and Regression to develop a cost model using the historical data of construction projects in Turkey. The models' accuracy was then evaluated by measuring the mean absolute percentage error. The effect of design and economic factors which were used as the input of the cost modes were then discussed in this study. This study further suggests using the economic factors alongside the design factors to develop more accurate cost models.