The Kansas City Preventive Patrol Experiment (KCPPE) was seen by its developers to have produced “consistent evidence of the lack of effects of any consequence on crime,” a conclusion that was to have a strong impact on assumptions about police patrol for almost half a century. We identified the original official crime data from the KCPPE, and reanalyzed outcomes focusing on a comparison of the “proactive” versus “control” beats (“reactive beats” were criticized because of violations of treatment integrity); examining broad categories of crime (to increase statistical power); and using count regression models. Our findings are not unequivocal, but point to modest impacts of police patrol on crime in police beats.

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警察大范围巡逻可以预防犯罪吗？重温堪萨斯城预防巡逻实验

堪萨斯城预防巡逻实验（KCPPE）被其开发者视为“没有任何后果对犯罪产生影响的一致证据”，这一结论在近半年的时间里对警察巡逻的假设产生了强烈影响。世纪。我们确定了 KCPPE 的原始官方犯罪数据，并重新分析了结果，重点是比较“主动”与“控制”节拍（“反应性节拍”因违反治疗完整性而受到批评）；检查广泛的犯罪类别（以提高统计能力）；并使用计数回归模型。我们的研究结果并不明确，但表明警察巡逻对警区犯罪的影响不大。