Understanding how motor carriers' size affects their productivity (e.g., miles per power unit) is of fundamental importance to carrier managers, shippers, and investors, because the nature of this relationship should influence carriers' strategies with regard to growth. In the truckload (TL) sector, the prevailing assumption is that TL carriers face constant returns to scale such that productivity differs little between large and small carriers. While empirical findings from several studies conducted since deregulation are consistent with this assumption, we contend that the true relationship between carrier size and productivity is more nuanced and is contingent on carriers' level of technical efficiency. Specifically, we develop and test middle range theory that predicts increasing returns to scale for carriers with low technical efficiency, constant returns to scale for carriers with average technical efficiency, and decreasing returns to scale for carriers with high technical efficiency. We test our theory by estimating production functions using quantile regression for data collected from the U.S. Department of Transportation for 1,068 TL carriers. Results from our analyses corroborate our predictions. Our findings hold valuable implications for the logistics literature as well as TL carrier management, shippers, and other industry stakeholders.

中文翻译：

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卡车载货汽车规模收益的新视角

对于承运人管理者，托运人和投资者来说，了解机动承运人的规模如何影响其生产率（例如，每动力装置的英里数）至关重要，因为这种关系的性质会影响承运人的增长战略。在卡车（TL）部门中，普遍的假设是TL承运人面临着规模报酬不变，因此大型和小型承运人之间的生产率差异很小。尽管从放松管制以来进行的几项研究得出的经验结果均与这一假设相符，但我们认为，承运人规模与生产率之间的真正关系更加细微，取决于承运人的技术效率水平。特别，我们开发并测试了中程理论，该理论预测技术效率低的航母的规模收益将增加，技术效率平均的航母的规模收益将恒定，技术效率高的航母的规模收益将减小。我们使用分位数回归估算生产函数来检验我们的理论，该分位数回归是针对从美国运输部收集的1,068个TL承运人的数据进行的。我们的分析结果证实了我们的预测。我们的发现对物流文献以及TL承运人管理，托运人和其他行业利益相关者具有宝贵的启示。我们使用分位数回归估算生产函数来检验我们的理论，该分位数回归是针对从美国运输部收集的1,068个TL承运人的数据进行的。我们的分析结果证实了我们的预测。我们的发现对物流文献以及TL承运人管理，托运人和其他行业利益相关者具有宝贵的启示。我们使用分位数回归估算生产函数来检验我们的理论，该分位数回归是针对从美国运输部收集的1,068个TL承运人的数据进行的。我们的分析结果证实了我们的预测。我们的发现对物流文献以及TL承运人管理，托运人和其他行业利益相关者具有宝贵的启示。