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2026 Vol.44, Issue 5 Preview Page

Article

Evaluating the Traffic Safety Effectiveness of the Minsik Law in School Zones: A Before–After Approach

민식이법 시행에 따른 어린이 보호구역 교통안전 개선효과 분석: Before-After 접근법을 중심으로

Keun Sub PARK1
,
Seong Jun PARK1
,
Yu LONG1
,
Euntak LEE2*
박 근섭1
,
박 성준1
,
용 우1
,
이 은탁2*
1Undergraduate, Division of Smart Cities, Korea University, Sejong 30019, Korea
2Assistant Professor, Division of Smart Cities, Korea University, Sejong 30019, Korea
1고려대학교 스마트도시학부 학부과정
2고려대학교 스마트도시학부 조교수
*Corresponding Author
31 October 2026. pp. 949-972
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Abstract

School zones are designed to protect child pedestrians, who are among the most vulnerable road users, and various regulatory and infrastructural measures have recently been implemented to improve traffic safety. Among these, the Minsik Law, enacted in South Korea in 2020, represents a major policy initiative aimed at strengthening driver regulations and expanding safety facilities within school zones. However, empirical evidence regarding its effectiveness in reducing traffic crashes remains limited. This study evaluates the safety effectiveness of the Minsik Law by applying three before-after approaches, such as Naïve, Empirical Bayes (EB), and Causal Forest (CF), to 30 school zones and 30 comparable non-school-zone sites in Seoul. Traffic crash records, along with average annual daily traffic, average travel speed, number of lanes, and number of enforcement cameras, were incorporated as covariates to estimate the policy effect. The results indicate that all three methods identified a reduction in crashes following the implementation of the Law. Among them, the CF model provided the most reliable estimates, yielding a Crash Modification Factor (CMF) of 0.80, a Safety Effectiveness (SE) of 20.3%, and an Average Treatment Effect (ATE) of -6.12. Furthermore, heterogeneous and differential treatment effect analyses revealed that the safety benefits of the policy were not uniform across school zones but varied according to roadway characteristics such as traffic volume, average travel speed, and the number of lanes. Beyond conventional average-effect evaluations, this study identifies the spatial heterogeneity and key determinants of policy effectiveness. The findings provide empirical evidence to support the prioritization of safety improvements and the development of tailored traffic safety policies for school zones.

Keywords
before-after analysis
causal forest
minsik law
school zone
traffic safety

어린이 보호구역은 교통약자인 어린이의 안전을 확보하기 위한 교통안전시설로, 최근 교통사고 예방을 위한 다양한 제도적･물리적 개선이 추진되고 있다. 특히 2020년 시행된 민식이법은 어린이 보호구역 내 안전시설 확충과 운전자 규제를 강화한 대표적인 교통안전 정책으로 평가받고 있으나, 정책의 실질적인 사고 감소효과를 정량적으로 검증한 연구는 아직 미흡하다. 본 연구는 민식이법 시행에 따른 어린이 보호구역의 교통안전 개선효과를 실증적으로 평가하기 위해 서울시 어린이보호구역 30개소와 일반도로 30개소를 대상으로 Naïve, Empirical Bayes, Causal Forest (CF) 기반 Before–After 분석을 수행하였다. 분석에는 교통사고 자료와 함께 일평균교통량, 평균 통행속도, 차로 수 및 무인단속카메라 수를 공변량으로 활용하여 정책효과를 비교분석하였다. 분석 결과, 세 방법론 모두 민식이법 시행 이후 교통사고 감소효과가 있음을 확인하였다. 그 중 CF 모형은 사고보정계수 0.80, 안전개선효과 20.3%, 평균처리효과 -6.12로 정책효과를 추정하였다. 또한 어린이보호구역의 사고 감소효과는 모든 구간에서 동일하게 나타나지 않았으며, 교통량, 평균 통행속도 및 차로 수와 같은 도로환경 특성에 따라 정책효과가 상이하게 나타남을 확인하였다. 본 연구에서는 기존의 평균효과 중심의 안전성 평가를 넘어 정책효과의 공간적 이질성과 영향요인을 규명하였다. 이는 향후 어린이 보호구역의 맞춤형 안전시설 설치 및 교통안전 정책의 우선순위 설정을 위한 실증적 근거를 제공할 것으로 기대된다.

키워드
Before-after 분석
Causal forest
민식이법
어린이 보호구역
교통안전
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Information
  • Publisher :Korean Society of Transportation
  • Publisher(Ko) :대한교통학회
  • Journal Title :Journal of Korean Society of Transportation
  • Journal Title(Ko) :대한교통학회지
  • Volume : 44
  • No :5
  • Pages :949-972
  • Received Date : 2026-06-30
  • Revised Date : 2026-07-22
  • Accepted Date : 2026-08-13
  • DOI :https://doi.org/10.7470/jkst.2026.44.5.949
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