Adopting and refining O’Brien’s S-constraint approach, we estimate age-period-cohort effects for motor vehicle theft offences in the United States for over half a century from 1960. Taking the well-established late-teen peak offending age as given, we find period effects reducing theft in the 1970 s, and period, but particularly cohort effects, reducing crime from the 1990s onwards. We interpret these effects as consistent with variation in the prevailing level of crime opportunities, particularly the ease with which vehicles could be stolen. We interpret the post-1990s cohort effect as triggered by a period effect that operated differentially by age: improved vehicle security reduced juvenile offending dramatically, to the extent that cohorts experienced reduced offending across the life-course. This suggests the prevailing level of crime opportunities in juvenile years is an important determinant of rates of onset and continuance in offending in birth cohorts. We outline additional implications for research and practice.

中文翻译：

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美国半个世纪以来盗窃机动车的年龄段影响

通过采用和完善O'Brien的S约束方法，我们估算了自1960年以来半个多世纪以来美国机动车盗窃犯罪的年龄段影响。我们发现，在1970年代，减少盗窃的时期效应以及从1990年代开始减少犯罪的时期，尤其是队列效应，尤其是队列效应。我们认为这些影响与当前犯罪机会水平的变化相一致，尤其是车辆被盗的难易程度。我们将1990年代后的群体效应解释为是由年龄效应引起的时期效应触发的：车辆安全性的提高极大地降低了青少年的犯罪行为，在某种程度上，该群体在整个人生过程中的犯罪行为有所减少。这表明，青少年时期犯罪机会的普遍水平是影响出生队列犯罪率和持续发生率的重要决定因素。我们概述了研究和实践的其他含义。