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281.
This paper analyses and discusses arguments that emerge from a recent discussion about the proper assessment of the evidential value of correspondences observed between the characteristics of a crime stain and those of a sample from a suspect when (i) this latter individual is found as a result of a database search and (ii) remaining database members are excluded as potential sources (because of different analytical characteristics). Using a graphical probability approach (i.e., Bayesian networks), the paper here intends to clarify that there is no need to (i) introduce a correction factor equal to the size of the searched database (i.e., to reduce a likelihood ratio), nor to (ii) adopt a propositional level not directly related to the suspect matching the crime stain (i.e., a proposition of the kind 'some person in (outside) the database is the source of the crime stain' rather than 'the suspect (some other person) is the source of the crime stain'). The present research thus confirms existing literature on the topic that has repeatedly demonstrated that the latter two requirements (i) and (ii) should not be a cause of concern.  相似文献   
282.
Since the mid-1990s, the index crime rate has steadily decreased while the rate for Part II offenses has increased. The current study examines these differences from 1990 to 2004 using arrest rate data from the 35 largest cities in the state of Texas. Cluster regression analyses is employed to examine the effect of city size and city location, whether the city is part of a larger metropolitan area or “stand-alone,” to explain variation in juvenile and adult arrest rates by category of offense (violent, property, Part II) while controlling for the influence of social disorganization variables. Findings indicate that differences exist in the arrest rates for almost all types of offenses in mid-size versus very large cities. Contrasting adult versus juvenile arrest rates, city size and city location offer limited explanation for variation over time. Implications of these findings are discussed in the context of suggested policy and research directions.  相似文献   
283.
The purpose of this article is to examine the attitudes and substance use behaviors of African American adolescents living in the Midwest. A baseline survey was administered to 463 African American teens between the ages of 11-19. The article examines the relationship between attitudes toward drugs and drug-using behavior in this African American sample. Drug use will be compared to national drug use norms established by the Youth Risk Behavior Surveillance Survey. Overall participants had fairly negative attitudes toward drugs. Sixty percent of the sample reported that they were committed to a drug-free life, 74% had made a decision to stay away from marijuana, 79% reported making a decision not to smoke cigarettes, and 71% reported they would not get drunk in the next year. Females were more likely to stay away from marijuana than males. In this current study there is cause for alarm; participants reported higher percentages of ever smoking cigarettes and marijuana than the Youth Risk Behavior Surveillance Survey. This study shows there is a need to provide substance abuse prevention programs for African American adolescents. Limitations and future directions are also discussed.  相似文献   
284.
Major campaign donors are highly concentrated geographically. A relative handful of neighborhoods accounts for the bulk of all money contributed to political campaigns. Public opinion in these elite neighborhoods is very different from that in the country as a whole and in low-donor areas. On a number of prominent political issues, the prevailing viewpoint in high-donor neighborhoods can be characterized as cosmopolitan and libertarian, rather than populist or moralistic. Merging Federal Election Commission contribution data with three recent large-scale national surveys, we find that these opinion differences are not solely the result of big-donor areas’ high concentration of wealthy and educated individuals. Instead, these neighborhoods have a distinctive political ecology that likely reinforces and intensifies biases in opinion. Given that these locales are the origin for the lion’s share of campaign donations, they may steer the national political agenda in unrepresentative directions.  相似文献   
285.
Sex determination is one of the essential steps in personal identification of an individual from skeletal remains. Most elements of the skeleton have been subjected to discriminant function analysis for sex estimation, but little work has been done in terms of the patella. This paper proposes a new sex determination method from the patella using a novel automated feature extraction technique. A dataset of 228 patellae (95 females and 133 males) was amassed from the William M. Bass Donated Skeletal Collection from the University of Tennessee and was subjected to noninvasive high resolution computed tomography (CT). After the CT data were segmented, a set of features was automatically extracted, normalized, and ranked. The segmentation process with surface smoothing minimizes the noise from enthesophytes and ultimately allows our methods to distinguish variations in patellar morphology. These features include geometric features, moments, principal axes, and principal components. A feature vector of dimension 45 for each subject was then constructed. A set of statistical and supervised neural network classification methods were used to classify the sex of the patellar feature vectors. Nonlinear classifiers such as neural networks have been used in previous research to analyze several medical diagnosis problems, including quantitative tissue characterization and automated chromosome classification. In this paper, different classification methods were compared. Classification success ranged from 83.77% average classification rate using labels from a Fuzzy C-Means (FCM) clustering step, to 90.3% for linear discriminant classification (LDC). We obtained results of 96.02% and 93.51% training and testing classification rates, respectively, using feed-forward backpropagation neural networks (NN). These promising results using newly developed features and the application of nonlinear classifiers encourage the usage of these methods in forensic anthropology for identifying the sex of an individual from incomplete skeletons retaining at least one patella.  相似文献   
286.
By questionnaire, 631 police investigators reported on their interrogation beliefs and practices-the first such survey ever conducted. Overall, participants estimated that they were 77% accurate at truth and lie detection, that 81% of suspects waive Miranda rights, that the mean length of interrogation is 1.6 hours, and that they elicit self-incriminating statements from 68% of suspects, 4.78% from innocents. Overall, 81% felt that interrogations should be recorded. As for self-reported usage of various interrogation tactics, the most common were to physically isolate suspects, identify contradictions in suspects' accounts, establish rapport, confront suspects with evidence of their guilt, and appeal to self-interests. Results were discussed for their consistency with prior research, policy implications, and methodological shortcomings.  相似文献   
287.
The current study examined psychopathy and nonverbal indicators of deception in an incarcerated sample. Nonverbal behaviors were coded from videotapes of 45 male offenders telling true and fabricated stories about crimes. Interpersonal features of psychopathy were associated with inflated views of lying ability, verbosity, and increases in blinking, illustrator use, and speech hesitations. While lying, the more psychopathic offenders spoke faster and demonstrated increases in blinking and head movements. Indicators of deception in offenders were somewhat different from those typically observed in non-offender populations. These findings indicate that personality factors may have an impact on nonverbal indicators of deception in criminal justice settings where the detection of deception is of utmost concern.  相似文献   
288.
This study examined how youths’ gender is related to the educational expectations of urban, low-income African American youth, their parents, and their teachers. As predicted, African American boys (ages 9–16) reported lower expectations for future educational attainment than did their female counterparts. Parents and teachers also reported lower expectations for African American boys (ages 6–16) than for girls. These findings held even when controlling for academic achievement. Contrary to predictions, the magnitude of the difference in expectations for males vs. females did not increase as a function of youths’ age. In keeping with our hypotheses, parental expectations fully mediated the relation between youths’ gender and youths’ expectations. Finally, certain school-based factors (i.e., positive teacher expectations and positive youth perceptions of the school environment) appeared to protect youths’ expectations from the deleterious impact of low parental expectations.
Dana WoodEmail:
  相似文献   
289.
Abstract:  We retrospectively reviewed autopsy records at a statewide medical examiner's office in order to identify and characterize deaths due to child abuse. In a 6-year period in New Mexico, the medical examiner investigated 45 deaths determined to be child abuse-related. Decedents were predominantly male (68.9%), Hispanic White (53.3%), and all were 5 years of age or younger, with a median age of 1 year. Head injuries were the most common cause of death (44.4%), followed by battered baby syndrome (15.6%). Relatives were involved as alleged perpetrators in 80% of the cases, with the father most often implicated (36.1% of cases), and 88.9% of child abuse injuries resulting in death occurred in the family's residence. Toxicology was positive in 26.7% of cases, but only two cases had substances of abuse present. Information on risk factors such as prematurity, parental age, and history of abuse was also collected.  相似文献   
290.
Abstract: The proper identification of illicit plants such as Papaver somniferum L (opium poppy) is important for law enforcement agencies. The identification of opium poppy was presently tested using 10 genetic markers that are universal for all plants or specific to a few poppy plants. The genetic distances of universal markers such as nuclear internal transcribed spacer (ITS), 18S rRNA, plastid rbcL, and trnL‐trnF intergenic spacer (IGS) of 14 species included in the Papaveraceae and Fumariaceae family were acquired by sequence comparisons. Both the ITS region and trnL‐trnF IGS showed high levels of interspecific divergence. Six Papaver genera‐specific markers were developed from coding regions involved in morphine biosynthesis. Three markers (TYDC, NCS, and BBE) produced amplicons only in opium poppy, providing a presence/absence test for opium poppy, while three additional markers (CYP80B1, SAT, and COR) were genus specific. These 10 markers might be useful for the forensic DNA analysis of opium poppy.  相似文献   
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