Using data of multi-vehicle crashes with drivers under the influence of alcohol/drugs in North Carolina from 2008 to 2017, this paper explores time-of-day variations (daytime vs. nighttime) and temporal instabilities of factors affecting alcohol/drug-impaired crash injury severities during three crash cycle phases after the Great Recession. Random parameters logit models with heterogeneity in the means and variances are utilized to identify significant factors, explore unobserved heterogeneity, reveal correlations between factors, and suggest possible impacts of economic conditions on the factors. Different likelihood ratio tests indicate that the effects of factors vary significantly across time-of-day and economic-related cycle periods. Significant time-of-day variations imply more severe injury alcohol/drug involved crashes during the nighttime compared to the daytime. Meanwhile, temporal instabilities are also observed in marginal effects of several factors across three-cycle periods. Proficient and cautious elder drivers were safer than young drivers during the depression period. Also, both depressing and expanding periods could affect the involvement of alcohol/drugs for drivers. Shifts in alcohol/drug use behaviors underscore the importance of accounting time-of-day variations, temporal instabilities, and heterogeneity in the means and variances inherent in alcohol/drug-impaired crash factors after the Great Recession. The insights of this study should be valuable to improve specific enforcements, qualify punishments, organize targeted campaigns, and design other preventive activities for alcohol/drug-impaired crashes.

本文使用 2008 年至 2017 年北卡罗来纳州在酒精/药物影响下与驾驶员发生多车相撞的数据，探讨了一天中的时间变化（白天与夜间）和影响酒精/药物受损的因素的时间不稳定性大萧条后三个碰撞周期阶段的碰撞伤害严重程度。利用均值和方差具有异质性的随机参数 logit 模型来识别重要因素，探索未观察到的异质性，揭示因素之间的相关性，并建议经济状况对因素的可能影响。不同的似然比检验表明，因素的影响在一天中的不同时间段和与经济相关的周期期间有显着差异。与白天相比，白天的显着变化意味着夜间与酒精/药物相关的车祸造成更严重的伤害。同时，在跨三个周期的几个因素的边际效应中也观察到时间不稳定性。在萧条时期，熟练而谨慎的老年司机比年轻司机更安全。此外，抑郁期和延长期都可能影响司机对酒精/药物的参与。酒精/药物使用行为的变化强调了在大萧条后考虑酒精/药物受损崩溃因素固有的均值和方差的时间变化、时间不稳定性和异质性的重要性。这项研究的见解对于改进具体执法、限定惩罚、组织有针对性的运动、