Research On Spatial Heterogeneity Of Urban Built Environment Impacts On Crime Behaviors

Security is the foundation that guarantees the normal operation of city economic activities and residents' life.Together with urbanization progress,the progressive rise of city crime rate has severely affected the behaviors,activities,living environment and quality of people and aggravated rigorous public security situation.Relevant studies concerning city crime also gradually arouse the attention in the academic circle.Space is the carrier of crime behaviors,while urban built environment is an important factor that affects the occurrence of crime behaviors.At the same time,urban built environment as a double-edged sword not only manipulates the occurrence of crime behaviors,but also prevents the occurrence of crime behaviors by built environment planning and design.As a result,how to prevent crime behaviors via environmental design gradually turns to be a hot spot of international research,while exploration of the influence of urban built environment on crime behaviors constitutes the foundation of such research.Relevant study in this field starts rather late in China and there still lacks sufficient study on specific practical situations,including systematic study based on “phenomenon-law-policy”,empirical study based on quantitative analysis method in combination with big data technique,and microscopic study based on macroscopic analysis.In consideration of domestic research gap and present city situation,the thesis takes quantitative analysis method and big data technology and chooses W City as the research region to empirically analyze the spatial variation about the influence of urban built environment on crime behaviors.During the analysis process,the thesis primarily adopts “phenomenon research-law research-strategy research” systematic research logic to focus on macroscopic level-based microscopic analysis and shorten the scale of analysis unit and eventually puts forward more pertinent crime prevention planning design strategy.Before analyzing the influence of city built environment on crime behaviors,it is essential to go into crime behaviors.The thesis chooses theft,contact fraud and robbery crime types closely related to built environment,and carries out an empirical analysis in six research regions from the perspective of time and space.In the meantime,in time dimension,the thesis further subdivides time into four dimensions including “day”,“week”,“hour” and “week” to observe three crime types.In space dimension,the thesis applies Moran's I,Gi* and kernel density estimation method to explore hot crime spots and cold spots in research regions and conducts a field investigation on the built environment of hot crime spots to lay a firm foundation for the selection of subsequent city built environment factors.There are numerous built environment factors that might affect crime behaviors.At present,domestic researches mainly focus on qualitative analysis or empirical analysis with single factor,but ignore systematic factor analysis from the empirical perspective.For compensating the research gap,the thesis considers contents in respect of daily activity theory,existing research foundation,field investigation in hot crime spots,data retrieval feasibility and systematically selects built environment factors that affect crime behaviors.Eventually,it starts from the perspective of land utilization to choose four types of factors covering land utilization diversity,plot ratio,public space and village in the city;starts from the perspective of city facility to choose five types of factors covering recreation facility,accommodation facility,business facility,finance facility,and public security facility;and starts from the perspective of street transportation to choose two types of factors covering street accessibility and public transportation station.Subsequent analysis on the spatial variation characteristics of all types of factors within research field paves way for the quantitative analysis about the influence of urban built environment on crime behaviors.In order to investigate the spatial variation about the influence of all city built environment factors on crime behaviors,the thesis takes geographic weighted regression method considering spatial heterogeneity as the analysis method and takes chosen built environment factors as the explanatory variables to observe the dependent variable of crime behaviors.First of all,the thesis uses multivariate regression analysis ordinary least square method to test the multicollinearity of explanatory variable;later applies ArcGIS 10.2 geographic weighted regression model to verify the spatial variation about the influence of urban built environment on crime behaviors and respectively verifies the spatial variation of theft behaviors,contact fraud behaviors and robbery behaviors;and finally interprets model analysis outcomes.For better explaining model analysis process and further inquiring the influence of built environment factors on crime behaviors from a macroscopic perspective,the thesis chooses three typical analysis units for field investigation.Firstly,the thesis analyzes the influence of three typical unit built environments on crime behaviors and spatial variation characteristics based on regression model analysis outcomes,and later analyzes the influence of population,social economy,land utilization,city facility and street transportation on crime behaviors in combination with the field investigation situation of three typical units.According to the spatial-temporal variation characteristics of crime behaviors and the spatial variation situation about the influence of urban built environment factors on crime behaviors,the thesis starts from the perspective of land utilization,city facility and street transportation to propose crime prevention planning designstrategies for different types of built environment factors.In combination with latest research results of urban-rural planning science,environmental criminology,and criminal geography,the thesis applies geographic weighted regression model to organize a quantitative analysis about the influence of urban built environment on crime behaviors.On the one hand,it has great theoretical values in enriching and developing the influence of urban built environment on crime behaviors and provides new theoretical basis for the exploration about the occurrence of crime behaviors.On the other hand,it formulates planning design strategies with crime prevention functions throughout the study on the spatial variation about the influence of city built environment factors on crime behaviors and has certain realistic significance to the improvement of urban security environment and residents' sense of security in life and activity.