dc.description.abstract |
Construction sector plays a leading role in economic growth for countries all around the
world and since construction is a labor-intensive industry, Productivity taken as a
primary driving force for economic development. Enhanced productivity helps
contractors not only to be more efficient and profitable but, knowing actual productivity
level helps them to estimate and be more competitive during bidding for projects. The
main objective of this research was to develop forecasting model that helps construction
stakeholders to predict construction labor productivity of block works by using multivariate
regression technique. In order to attain the objective, a detailed literature review
was done and 32 factors that had tangible impact on construction labor productivity were
listed and grouped in 8 groups namely: Manpower related, Motivation related, Materials
and tools related, Supervision related, Project related, Time related, Quality related and
External factors. A questionnaire survey was conducted on ongoing building
construction projects in Bahir Dar city. Simple random sampling technique was used to
collect the data’s. Based on the result of the survey, from the 31 factors 8 were selected
as most significant factors based on their RII value. These nine factors were then
subjected to Principal component analysis method in order to reduce their number, and
four factors (Crew size, Labor’s skill, Store location and Construction method) were
factored out for the model formulation process. From the collected data 80% were used
in the training set or model formulation. Multi-Variate regression was done using SPSS
(statistical package for social studies) to generate the forecasting model. A forward
selection method was used in developing the model, which resulted in R2 value of 77.7%
which indicates a good predicting capability of the model. Finally, the developed model
was validated by using the remaining 20% of collected data and resulted in small amount
of mean average percentage error (MAPE=5.19%). The developed predicting model
helps construction stakeholders mainly contractors in Bahir Dar city in the initial stages
of construction by providing them a predicting formula. And also Contractors are advised
to give serious attention for the factors listed out in this paper as they have a great impact
in affecting construction labor productivity.
Keywords: Construction labor productivity, Model formulation, Multi-variate
regression, Productivity |
en_US |