Most truckload freight in the United States is priced using long-term contracts. It is widely recognized in industry that contract prices evolve based on prices shippers pay for one-time spot market transactions. This research examines whether the impact of spot market prices on contract prices has become more pronounced following the start of the electronic logging device (ELD) mandate. We draw on economic theories regarding how firms process information to explain why the ELD mandate, by reducing carriers’ ability to artificially adjust capacity up or down as spot prices changed, should strengthen this relationship. To test this prediction, we construct a database that combines monthly proprietary spot market pricing data from DAT Solutions with monthly public contract pricing data from the Bureau of Labor Statistics. We test our predictions using time series regression and evaluate the robustness of our findings using both instrumental variable estimation and seemingly unrelated regression to rule out reverse causality. Consistent with our theorizing, we further this relationship has become more pronounced since the ELD mandate started. We explain the importance of these findings to theory and practice.

中文翻译：

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卡车运输部门的定价动态：电子记录设备指令的调节作用

美国的大多数卡车货运都是使用长期合同定价的。业内普遍认为，合同价格的演变基于托运人为一次性现货市场交易支付的价格。这项研究检验了现货市场价格对合同价格的影响是否在电子记录设备 (ELD) 授权开始后变得更加明显。我们利用关于公司如何处理信息的经济理论来解释为什么 ELD 要求通过降低运营商随着现货价格变化人为地调整运力的能力来加强这种关系。为了测试这一预测，我们构建了一个数据库，该数据库将来自 DAT Solutions 的月度专有现货市场定价数据与来自劳工统计局的月度公共合同定价数据相结合。我们使用时间序列回归测试我们的预测，并使用工具变量估计和看似无关的回归来评估我们发现的稳健性，以排除反向因果关系。与我们的理论一致，我们进一步认为，自 ELD 授权开始以来，这种关系变得更加明显。我们解释了这些发现对理论和实践的重要性。