INTEGRATING MODEL TREE AND MODIFIED STEPWISE REGRESSION IN CONCRETE SLUMP PREDICTION AND STEEL FABRICATION ESTIMATING

The model tree algorithm of M5 is integrated with the multiple linear regression technique called modified stepwise regression (MSR), resulting in a new methodology for modeling complex civil engineering problems. We purposefully chose artificial neural networks (ANN) for comparison against the proposed “M5+MSR” because they fall at the two ends of the model interpretability spectrum in machine learning. In two application cases (case 1: concrete workability and case 2: steel fabrication estimating), the proposed “M5+MSR” gave rise to explainable regression tree models featuring substantially reduced complexities against ANN and model prediction errors comparable to ANN. In both cases, the resulting “M5+MSR” models consistently outperformed ANN in terms of model overfitting metrics by 19% in case 1 and by 21% in case 2, thus boasting better learning performances. The proposed new methodology will potentially find applications in tackling a wide range of complicated engineering problems that entail fitting prediction models based on laboratory or field data.

Interaction effect of entrepreneurial orientation and stakeholder orientation on the business performance of firms in the steel fabrication industry in Thailand

Purpose The purpose of this paper is to explore the interaction effect of entrepreneurial orientation and stakeholder orientation on the business performance of small and medium enterprises. In particular, four components of stakeholder orientation including customer orientation, competitor orientation, employee orientation and shareholder orientation were considered as the moderating factors to analyze the interaction effect between each of these stakeholder groups and the entrepreneurial orientation on firms’ performance. This research used resources-based views of firms and stakeholder theory as an integrated theoretical framework to explain the interaction effect of entrepreneurial orientation and stakeholder orientation on firms’ performance. Design/methodology/approach Survey data were collected from 370 small and medium firms in the steel fabrication industry in Thailand using probability sampling. Partial least-squares structural equation modeling was used for model estimation. Findings The results significantly supported a positive contribution of entrepreneurial orientation to firms’ performance. The moderating effect analysis additionally found that the contribution of entrepreneurial orientation to firms’ performance was positively moderated by customer orientation but negatively moderated by shareholder orientation. Originality/value This research extended prior studies on entrepreneurial orientation by using resource-based views of firms and stakeholder theory as an integrated theoretical framework to explain the interaction effect of entrepreneurial orientation and stakeholder orientation on firms’ performance.

Framework for developing labour-hour prediction models from project design features: case study in structural steel fabrication

Assigning labour-hours to a certain scope of work during design and estimating is still more of an art than a science. This research proposes a data-driven approach that uses multiple linear regression (MLR) and available historical data from building information models (BIM) to associate project labour-hours and project design features. The framework relies on an enhanced version of stepwise regression technique to select the most relevant predictive factors and generate a predictive model without compromising the achievable accuracy of regression. The framework also encompasses analytical methods for justifying MLR application, validating the resulting model, and establishing range estimates for point-value predictions. In collaboration with an industry partner, the framework application is exemplified by analyzing labour-hours and design features for structural steel fabrication, leading to the creation of a valid MLR model in the simplest form. Finally, pros and cons for the proposed framework and opportunities for future research are discussed.