An Effective Approach to Input Variable Selection for Preliminary Cost Estimation of Construction Projects

Table 2

Identified input variables.

Input variables	References
Project type	[12, 54]
Project complexity	[7, 10]
Project location	[10–12, 21, 28, 33, 54, 58]
Project scope	[7, 11, 12, 26, 54]
Project size	[8, 11, 12, 21, 26, 54]
Site topography	[12, 21, 25, 56, 59]
Bridge type	[21, 23]
Number of bridges	[12, 21, 23]
Existence of groundwater	[12]
Soil type	[12, 26, 56, 60]
Inflation rate	[11, 12, 54]
Project duration	[7, 10, 12, 21, 26]