The current study proposes an approach that accounts for the importance of streets while at the same time accounting for the overlapping spatial nature of social and physical environments captured by the egohood approach. Our approach utilizes overlapping clusters of streets based on the street network distance, which we term street egohoods.
Methods
We used the street segment as a base unit and employed two strategies in clustering the street segments: (1) based on the First Order Queen Contiguity; and (2) based on the street network distance considering physical barriers. We utilized our approaches for measuring ecological factors and estimated crime rates in the Los Angeles metropolitan area.
Results
We found that whereas certain socio-demographics, land use, and business employee measures show stronger relationships with crime when measured at the smaller street based unit, a number of them actually exhibited stronger relationships when measured using our larger street egohoods. We compared the results for our three-sized street egohoods to street segments and two sizes of block egohoods proposed by Hipp and Boessen (Criminology 51(2):287–327, 2013) and found that two egohood strategies essentially are not different at the quarter mile egohood level but this similarity appears lower when looking at the half mile egohood level. Also, the street egohood models are a better fit for predicting violent and property crime compared to the block egohood models.
Conclusions
A primary contribution of the current study is to develop and propose a new perspective of measuring neighborhood based on urban streets. We empirically demonstrated that whereas certain socio-demographic measures show the strongest relationship with crime when measured at the micro geographic unit of street segments, a number of them actually exhibited the strongest relationship when measured using our larger street egohoods. We hope future research can use egohoods to expand understanding of neighborhoods and crime.
Several Canadian and international scholars offer commentaries on the implications of the COVID-19 pandemic for governments and public service institutions, and fruitful directions for public administration research and practice. This first suite of commentaries focuses on the executive branch, variously considering: the challenge for governments to balance demands for accountability and learning while rethinking policy mixes as social solidarity and expert knowledge increasingly get challenged; how the policy-advisory systems of Australia, Canada, New Zealand, and United Kingdom were structured and performed in response to the COVID-19 crisis; whether there are better ways to suspend the accountability repertoires of Parliamentary systems than the multiparty agreement struck by the minority Liberal government with several opposition parties; comparing the Canadian government’s response to the COVID-19 pandemic and the Global Financial Crisis and how each has brought the challenge of inequality to the fore; and whether the COVID-19 pandemic has accelerated or disrupted digital government initiatives, reinforced traditional public administration values or more open government. 相似文献
From Aliens to Citizens: Redefining the Status of Immigrants in Europe. Rainer Bauböck (Ed.), 1994, Aldershot/Brookfield, Avebury, 233 pp., pbk. ISBN 1 85972 059 5
The Challenge of Diversity: Integration and Pluralism in Societies of Immigration Rainer Bauböck, Agnes Heller, Aristide R. Zolberg (Eds), 1996, Aldershot/Brookfield, Avebury, 279 pp., pbk. ISBN 1 85972 401 9 相似文献
The storage and use of explosives is regulated at the state and federal level, with a particular focus on physical security and rigorous accounting of the explosive inventory. For those working with explosives for the training and testing of explosive-detecting canines, cross-contamination is an important concern. Hence, explosives intended for use with canine teams must be placed into secondary storage containers that are new, clean, and airtight. A variety of containers meet these requirements and include screw-top glass jars (e.g., mason jars). However, an additional need from the explosive-detecting canine community is secondary containers that can also be used as training aids whereby the volatiles emitted by explosives are emitted in a predictable and stable manner. Currently, a generally accepted method for the storage of explosives and controlled emission of explosive vapor for canine detection does not exist. Ideally, such containers should allow odor to escape from the training aid but block external contaminates such as particulates or other volatiles. One method in use places the explosive inside a permeable cotton bag when in use for training and then stores the cotton bag inside an impermeable nylon bag for long-term storage. This paper describes the testing of an odor permeable membrane device (OPMD) as a new way to store and deploy training aids. We measured the evaporation rate and flux of various liquid explosives and volatile compounds that have been identified in the headspace of actual explosives. OPMDs were used in addition to traditional storage containers to monitor the contamination and degradation of 14 explosives used as canine training aids. Explosives were stored individually using traditional storage bags or inside an OPMD at two locations, one of which actively used the training aids. Samples from each storage type at both locations were collected at 0, 3, 6, and 9 months and analyzed using Fourier Transform Infrared (FTIR) Spectroscopy and Gas Chromatography–Mass Spectrometry (GC–MS) with Solid-Phase Microextraction (SPME). FTIR analyses showed no signs of degradation. GC–MS identified cross-contamination from ethylene glycol dinitrate (EGDN) and/or 2,3-dimethyl-2,3-dinitrobutane (DMNB) across almost all samples regardless of storage condition. The contamination was found to be higher among training aids that were stored in traditional ways and that were in active use by canine teams. 相似文献