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101.
Whereas one line of recent neighborhood research has placed an emphasis on zooming into smaller units of analysis such as street blocks, another line of research has suggested that even the meso‐area of neighborhoods is too narrow and that the area surrounding the neighborhood is also important. Thus, there is a need to examine the scale at which the social ecology impacts crime. We use data from seven cities from around the year 2000 to test our research questions using multilevel negative binomial regression models (N = 73,010 blocks and 8,231 block groups). Our results suggest that although many neighborhood factors seem to operate on the microscale of blocks, others seem to have a much broader impact. In addition, we find that racially and ethnically homogenous blocks within heterogeneous block groups have the most crime. Our findings also show the strongest results for a multitude of land‐use measures and that these measures sharpen some of the associations from social characteristics. Thus, we find that accounting for multiple scales simultaneously is important in ecological studies of crime.  相似文献   
102.
In many Western countries, citizen knowledge of terrorist events is intrinsically shaped by the style of broadcasted messages published by the media. Media discourses regarding terrorist acts raise questions about how such rhetoric elicits fear in people who typically experience such events through news reports. However, we do not fully understand the impact of the media on perceptions of terrorism as clearly as we understand the relationship between the media and fear of crime. This study examines how media sources accessed actively (e.g. through newspapers; Internet) or passively (e.g. through television; radio) influence knowledge and fear of terrorism. We find receiving information about terrorism from multiple media sources increases fear of terrorism, but media sources accessed passively are not as influential as media sources accessed more actively. These results highlight how media consumption from various sources may affect one’s fear of terrorism, and further illustrates how the role of perceived knowledge may exacerbate or mitigate fear. Implications for policy and practice are discussed.  相似文献   
103.
Juvenile age estimation methods used in forensic anthropology generally lack methodological consistency and/or statistical validity. Considering this, a standard approach using nonparametric Multivariate Adaptive Regression Splines (MARS) models were tested to predict age from iliac biometric variables of male and female juveniles from Marseilles, France, aged 0–12 years. Models using unidimensional (length and width) and bidimensional iliac data (module and surface) were constructed on a training sample of 176 individuals and validated on an independent test sample of 68 individuals. Results show that MARS prediction models using iliac width, module and area give overall better and statistically valid age estimates. These models integrate punctual nonlinearities of the relationship between age and osteometric variables. By constructing valid prediction intervals whose size increases with age, MARS models take into account the normal increase of individual variability. MARS models can qualify as a practical and standardized approach for juvenile age estimation.  相似文献   
104.
Pepper spray (OC) is a policing tool aimed to prevent or stop aggressive behavior by quickly and temporarily incapacitate without injuring. To date, few studies have investigated OC’s operational usefulness and limitations. OC reduced violent behavior in 93% of the 936 incidents investigated. However, the operative range was often <2 m and it took between 3 and 5 s of spraying before obtaining effect, partly owing to the difficulties of hitting a small, sometimes erratically moving target. Collateral hits were noted in 24% of the incidents, whereof 90% were other officers. Noteworthy, in 21% of incidents officers put themselves at large personal risk by using OC at close range against people armed with lethal weapons. Hence, OC emerges as a suitable tool for handling low threat situations but lacks key traits to ensure safe and efficient policing of high threat situations, e.g., handling armed assailants.  相似文献   
105.
106.
Canines are usually used in anthropological and forensic sciences for sex and age determination. The best methods to estimate age are based on secondary dentine apposition, evaluated from periapical X-rays. The aim of this study was to propose a new method of sex and age estimation using 3D models to obtain more precise predictions using tooth volumes. Fifty-eight dental CT scans of patients aged 14-74 with a well-balanced sex ratio composed the sample. One hundred and thirty-three healthy canines were modeled (Mimics 12.0). The sample was divided into a training sample and a validation sample. An age formula was determined using the "pulp volume/tooth volume" ratio. Sex prediction was adjusted with total volumes. Applying the equations to the validation sample, no significant difference was found between the real and predicted ages, and 100% of the sex predictions were correct. This preliminary study gives interesting results, and this method is worth being tested on a larger data sample.  相似文献   
107.
Even though trace evidence is becoming more and more important in legal cases, only little is known about the influence of task and context factors on comparative judgments. In the present study we investigated how expectations and complexity affect shoe print examinations and to what extent differences exist between beginners and experienced examiners. Twelve examiners assessed similarity between a shoe print and a shoe for eight different cases. For half the cases expectation was induced by providing additional incriminating evidence. A complex case meant that the print was relatively noisy, for example because the perpetrator rotated his foot. A simple case meant that the print was clear. The results showed that there was no effect of expectation and no effect of experience. Only complexity affected the examiners' assessments: when the background was noisy, the acquired features received a lower evidential value than when the background was clear. Apparently, examiners compensated for the quality of the print and were more cautious in drawing conclusions when prints were less clear. Even though the results allow for some optimism with regard to the influence of expectations on shoe print examinations, it has to be taken into account that the Dutch procedure is supported by a formal guideline, which may (partly) explain the present findings.  相似文献   
108.
Berk criticizes meta-analysis on a host of statistical grounds. The criticisms are thoughtful, and may even seem compelling on first read. However, his criticisms are really a special case of the kinds of criticisms that can be leveled at all scientific endeavor. Science is rife with assumptions of greater or lesser plausibility, no more so in meta-analysis than in primary research. We trust in those assumptions only temporarily and heuristically. The answer is not to abandon ship, but rather to work to improve the endeavor at the margin, hoping that science is self-correcting in the long-run, and that our answers are not too far off despite the weaknesses of the enterprise.
William R. ShadishEmail:
  相似文献   
109.
The purpose of the present study was to examine the direct and indirect effects (through peer contacts) of parental knowledge on adolescents’ delinquent and aggressive problem behavior, using latent growth curve modeling. A sample of 457 13- to 14-year old adolescents at first measurement wave (M=13.27; SD=0.45 years) filled out questionnaires about their parents, peers, and problem behavior three times with 1-year intervals in between. Regarding initial levels of behavior, both direct and indirect effects of parental knowledge were found on aggressive as well as on delinquent behavior. When the rate of change in behaviors was considered, only direct effects were found for both types of problem behavior, whereas indirect effects were absent. Gender differences were also found, with stronger effects of parenting on both aggressive and delinquent problem behavior for boys and stronger effects of peer contacts on aggressive behavior for girls. The present study shows that different behaviors of the externalizing spectrum have different trajectories and diverse relations with parenting and should not be treated as identical.
Kirsten L. BuistEmail:
  相似文献   
110.
Abstract: Likelihood ratios (LRs) provide a natural way of computing the value of evidence under competing propositions. We propose LR models for classification and comparison that extend the ideas of Aitken, Zadora, and Lucy and Aitken and Lucy to include consideration of zeros. Instead of substituting zeros by a small value, we view the presence of zeros as informative and model it using Bernoulli distributions. The proposed models are used for evaluation of forensic glass (comparison and classification problem) and paint data (comparison problem). Two hundred and sixty‐four glass samples were analyzed by scanning electron microscopy, coupled with an energy dispersive X‐ray spectrometer method and 36 acrylic topcoat paint samples by pyrolysis gas chromatography hyphened with mass spectrometer method. The proposed LR model gave very satisfactory results for the glass comparison problem and for most of the classification tasks for glass. Results of comparison of paints were also highly satisfactory, with only 3.0% false positive answers and 2.8% false negative answers.  相似文献   
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