赤脚足迹的统计分析

在犯罪现场,依据遗留的足迹和鞋,尽快认定和排除犯罪嫌疑人是非常重要的。赤脚足迹的形态比对,在刑事侦查中是十分有价值的。此项研究表明:从众多嫌疑人中提取的赤脚足迹,通过轮廓线条的测量显示出巨大的差异性;从同一嫌疑人提取的多个足迹却显示出很大的一致性。这项研究所精选的足迹测量的系列标准已得到证实。作为个人特征识别的一种统计规律,它的测量精度正在进一步提高。     

Developing a Multicenter Randomized Trial in Criminology: The Case of HIDTA

In criminal justice, as in other fields, an experimental study conducted ata single site does not offer a solid basis upon which to make strong publicpolicy recommendations. To date, criminal justice researchers have reliedupon two general approaches to overcome the limitations of single-siteexperimental research. The first, termed ``meta-analysis, seeks tocombine independent studies to identify consistent effects across criminaljustice settings or contexts. The second, sometimes termed replicationstudies, seeks to replicate investigations in multiple criminaljustice jurisdictions. In this paper we describe a related approachdeveloped in clinical studies in medicine and examine its applicabilityin criminal justice settings. Termed a multicenter clinicaltrial, this method demands the implementation ofa single experimental protocol at multiple sites. We contrast themulticenter approach with other methods and provide a substantiveexample of an ongoing multicenter criminal justice study. We begin byexamining the specific limitations of current approaches and solutionsoffered by multicenter studies to overcome these. We then turn to anapplication of the multicenter clinical trial in a criminal justicesetting. Using the example of the HIDTA (High-Intensity Drug TraffickingAreas) evaluation of drug treatment programs currently being conducted atmultiple sites, we illustrate components of the multicenter approach aswell as potential drawbacks researchers are likely to face in itsapplication in crime and justice studies.     

基于决策者视角的统计改革建议改进方略

探索改革或创新的理论研究及工作研究成果,不少以管理对策、政策建议、创新思路或改革方案等形式出现,可合称为＂改革建议＂。提出有影响力的改革建议的过程,本身就是建议者的自我管理控制过程。文章以政府统计为例,探讨如何让改革建议跟上改革需要,并分析了部分建议的五个缺陷及相应的九个改进方略。     

新时期规范统计执法检查的对策

规范统计执法检查，就是要在确保统计数据质量的前提下，提高全民统计法律意识和统计执法人员的执法水平。文章从统计执法检查不力的成因和采取对策的角度，就规范统计执法检查的相关问题作一探讨，以期达到统计数据的真实性、准确性，实现依法统计。     

对《公安统计学》教学的几点思考

《公安统计学》是一门实用性很强同时又较难掌握的学科,如何在学生中建立较高的统计学教学地位,培养学生学习兴趣,使其能够运用统计学基本理念和统计分析方法解决实际问题,正是公安统计教学所追求的目标。本文从教育理念、教学内容、教学手段和方法等方面对《公安统计学》教学进行了思考。     

我国证券市场结构突变与波动性实证研究

重大事件的发生会使证券市场波动率发生结构突变.通过修正ICSS算法检验,可以发现我国证券市场波动存在明显的结构变化.将结构突变因素加入波动率模型进行比较后,可以发现含结构突变的波动率模型能更准确地刻画波动率特征.再分别按照结构突变发生的时间点分割样本区间与构造虚拟变量两种方法,对含结构突变的波动率模型进行比较研究的结果表明:构造虚拟变量方法对我国证券市场的波动率建模能取得较好的统计效果.     

Validation of Toolmark Comparisons Made At Different Vertical and Horizontal Angles

Numerous studies have focused on determining whether objective statistical methods can be used to discriminate between known matches and nonmatches when comparing laboratory prepared toolmarks. This study involved an analysis of striated toolmarks made as a function of varying vertical and horizontal angles of attack. Comparisons based on experimental data show that replicate toolmarks from the same tool show high correlation values at identical vertical and horizontal angles, with the correlation decreasing as the angular difference increases, especially for horizontal angular changes. Comparisons between nonmatching samples produce low correlation values that remain unchanged as horizontal angular differences increase. While complete statistical separation was not achieved between matching and nonmatching samples, there is evidence demonstrating that toolmarks can be identified if the variation in horizontal angle is within 10°. The experiment shows that computer‐aided comparison techniques could be viable for identification with the proper statistical algorithm.     

Wavelet Analysis of Resultant Velocity Belonging to Genuine and Forged Signatures

This study presents a wavelet analysis of resultant velocity features belonging to genuine and forged groups of signature sample. Signatures of individuals were initially classified based on visual human perceptions of their relative sizes, complexities, and legibilities of the genuine counterparts. Then, the resultant velocity was extracted and modeled through wavelet analysis from each sample. The wavelet signal was decomposed into several layers based on maximum overlap discrete wavelet transform (MODWT). Next, the zero crossing rate features were calculated from all the high wavelet sub‐bands. A total of seven hypotheses were then tested using a two‐way ANOVA testing methodology. Of these, four hypotheses were conducted to test for significance differences between distributions. In addition, three hypotheses were run to provide test for interaction between two factors of signature authentication versus perceived classification. The results demonstrated that both feature distributions belonging to genuine and forged groups of samples cannot be distinguished by themselves. Instead, they were significantly different under the influence of two other inherent factors, namely perceived size and legibility. Such new findings are useful information particularly in providing bases for forensic justifications in establishing the authenticity of handwritten signature specimens.     

'Nuisance' phone calls to women in England and Wales

Obscene or nuisance phone calls are particularly targeted towards women. Employing data from two sweeps of the British Crime Survey a decade apart (BCS 1982 and BCS 1992), this work attempts to measure the effects of individual socio-economic characteristics and victimization history of women in England and Wales on their likelihood of receiving at least one nuisance call. To make the logit modelling analysis more tangible, risks of nuisance calls are calculated from our models of five hypothetical women, single mother, professional, student, housewife and pensioner, with specific attributes taken from the set of explanatory variables.     

青少年违法犯罪的多元统计分析

根据"武汉市同龄群青少年违法犯罪纵向跟踪调查报告"所提供的青少年违法犯罪与12个因素之间关系的调查数据,对青少年违法犯罪和这12个因素之间进行了品质相关分析,且从中选出品质相关系数最大的四个因素建立线性统计(Logistic回归)模型,并引入调整发生比率AOR,详细分析了模型中的4个因素对青少年违法犯罪的影响程度。