Collaborative Research on Spatial and Temporal Dynamics of Urban Homicide

9422272 Kohfeld本研究的总体目标是解释1960-1994年期间圣路易斯凶杀案时空分布的长期和短期变化。 该项目的具体目标由两个假设构成：扩散假设，根据杀人事件相互直接联系的人际过程解释杀人的变异性;独立生成假设，根据社会生态条件的变化解释杀人的变异性。 在35年的研究期间，从警方记录中对个人杀人事件进行了详细编码，以提供高度分化的杀人事件分类。 这些事件是按选定的时间间隔、不同的空间单位和不同的杀人类型汇总的。 分析战略是对按照受害者和罪犯的特征（种族、性别、年龄）和事件（枪支）分类的杀人事件在系统的不同时间和空间单位进行反复的横截面分析。毒品，帮派，受害者-罪犯关系）。 一个创新的特点是使用地理信息系统软件作为衡量杀人事件和预测中使用的其他措施的基本组成部分。 分析进行了我们的统计模型，适合高度偏态分布的事件，如杀人。 完整的数据集将包括自1960年以来在圣路易斯发生的5000多起凶杀案，1950-1990年人口普查的数据，以及旨在测量相关行为过程的其他来源的数据。 这项研究将对城市凶杀案的空间和时间结构作出全面的说明，从而促进对这一严重的国家问题的科学认识。 这是一项关于1960-1994年期间圣路易斯凶杀案分布的研究。 它考察了时间和空间上的分布，以测试两个不同的假设，以解释谋杀的分布和发生。 扩散假说将凶杀解释为人际行为的结果，这些行为将一个凶杀与另一个凶杀直接联系起来。 独立世代假说将杀人解释为社会经济条件变化的结果。 为了研究这些假设，本研究将非常详细地对圣路易斯凶杀案的特征进行编码，然后在不同的时间段和空间单位中汇总凶杀案及其特征。 对这些综合凶杀模式的分析将涉及对凶杀案最突出的特征进行反复的横断面分析，这些特征包括受害者和罪犯的特征（例如，种族、性别、年龄）和杀人事件（例如，事件是否涉及枪支、毒品、帮派或某些受害者-犯罪者关系）。 地理信息软件将在组织、显示、处理和分析凶杀案数据方面发挥重要作用。 分析将基于5,000多起凶杀案。 将产生的数据集将包括关于5 000起杀人案的数据，加上来自人口普查和其他来源的按地理和时间组织的数据，这些数据与衡量与解释杀人案有关的行为过程有关。 统计分析将针对偏态分布，如杀人数据的特点。 研究结果将提供一个全面的结构或城市凶杀案，这将促进对这一严重的国家问题的科学认识。 ****

9422272 Kohfeld The overall objective of this research is to explain both long- and short-run changes in the temporal and spatial distribution of homicide in St. Louis over the period 1960-1994. Two hypotheses frame the specific aims of the project: the diffusion hypothesis, which accounts for variability in homicide on the basis of interpersonal processes that directly link homicide events to one another, and the independent-generation hypothesis, which accounts for variation in homicide in terms of changes in social-ecological conditions. Individual homicide events are coded in detail from police records for the 35-year period of study to provide a highly differentiated classification of homicide events. These events are aggregated for selected time intervals, for varying spatial units, and for varying homicide types. The analytic strategy is to conduct repeated cross-sectional analyses over systematically varied units of time and space for homicide events classified according to characteristics of victims and offenders (race, gender, age) and incidents (gun. drug, gang, victim-offender relationship). An innovative feature is the use of geographic information system software as a fundamental component of the measurement of both homicide events and other measures used in prediction.. The analyses are carried our with statistical models appropriate for the highly skewed distributions of events such as homicide. The completed data set will include more than 5.000 homicides that have occurred in St. Louis since 1960, data from the census years 1950-1990, and data from other sources designed to measure related behavioral processes. The research will produce a comprehensive account of the spatial and temporal structure of urban homicide that can advance scientific understanding of a serious national problem. %%% This is a study of the distribution of homicide in St. Louis over the period 1960-1994. It examines that distribution over both time and space to test two differing hypotheses advanced to explain the distribution and occurrence of murders. The diffusion hypothesis explains homicide as the result of interpersonal behaviors that directly link one homicide with another. The independent-generation hypothesis explains homicide as the result of changes in socioeconomic conditions. To investigate the hypotheses, this study will code the characteristics of St. Louis homicides in great detail and then aggregate homicide and their characteristics across various periods of time and units of space. The analysis of these aggregated homicide patterns will involve repeated cross-sectional analyses for the most salient characteristics of the homicides, characteristics such as traits of victims and offenders (e.g., race, gender, age) and of the homicide incident (e.g., whether the incident involves guns, drugs, gangs, or certain victim-offender relationships). Geographic information software will play an important role in organizing, displaying, manipulating, and analyzing the homicide data. The analysis will be based on more than 5,000 homicides. The data set to be produced will include the data on the 5,000 homicides plus geographically- and temporally-organized data from censuses and other sources relevant to measuring behavioral processes related to explaining homicide. The statistical analyses will be tailored for skewed distributions such as those characterizing homicide data. The research results will provide a comprehensive account of the structure or urban homicide that will advance scientific understanding of this serious national problem. ****