## 1 Introduction  
Many activities in the construction sector are labor intensive, so construction labor productivity (CLP) has a significant impact on time, cost, and quality of a construction project [1, 2]. CLP is defined as a ratio of output (i.e., installed quantity) to input (e.g., labor work hours) or vice versa. Therefore, maximizing CLP is pivotal for enhancing the overall performance of construction projects in multiple areas, such as reducing variances from the primary plan and keeping projects on time and within budget. Therefore, construction companies are required to implement various CLP improvement strategies to enhance the level of influencing CLP factors and consequently improve CLP. In this study, a CLP improvement strategy is an individual management practice, such as a working method, tactic, or innovation, that construction managers use to improve CLP on their projects. Some examples of CLP improvement strategies include performing weekly reviews of crew compositions to ensure crew mix is per plan, providing clear instructions to craftspeople on how to complete tasks prior to execution, and scheduling regular inspections by the owner team to reduce interventions during project execution. However, budget, time, and resource constraints force construction companies to carry out only a limited number of CLP improvement strategies [3]. Furthermore, in the complex environment of construction, CLP is affected by numerous factors that are mostly interconnected [4, 5]. Thus, the actual impact of various factors on CLP can only be obtained using a systematic approach that models the interrelationships among them [6]. However, most construction companies apply management practices, such as changing working times and switching the workweek, based on their managers' experience and knowledge [7]. Understanding factors that affect labor productivity is important for making strategic decisions and selecting appropriate CLP improvement strategies [8]. Factors affecting CLP are multilevel, ranging from the activity level to the project, national, and global levels [9; 10]. Therefore, different opinions of a construction company's personnel (e.g., project managers, craft workers, foremen) should be captured to determine the importance of CLP factors for CLP improvement [11]. To identify factors that affect CLP, previous studies integrated the perspective of different project participants through questionnaires with interview surveys and grouped the CLP factors under various categories to analyze them. For instance, [PERSON] et al. [12] identified and ranked 45 critical CLP factors out of 203 samples collected from project managers and contractors via a survey questionnaire. Their results' analysis showed a significant difference between project manager's and contractors' opinions on the key factors affecting CLP. [PERSON] et al. [13] developed a questionnaire containing 30 factors affecting CLP in Libya. Their results indicated that a lack of labor supervision and the experience and skill of labor are the most significant factors affecting CLP in Libyan construction projects. Compared to CLP factors identification, very few studies have been conducted for identifying key CLP improvement strategies. According to the provided literature review, most techniques proposed for selecting key CLP improvement strategies lack the capability to quantify the strategies' impact on CLP. However, to effectively improve CLP, the extent to which the implemented improvement strategies affect CLP needs to be known. Widely used techniques for quantifying the impact of various strategies on CLP include statistical methods such as _t_-test and regression analysis [7; 14]. The major limitation of statistical methods is their inability to capture the causal relationships among CLP factors, improvement strategies, and CLP. In addition, such methods lack the capability to consider project characteristics. However, key CLP improvement strategies differ from one project to another.