Contrasting simulated and empirical experiments in crime prevention

This paper argues that simulated experiments of crime prevention interventions are an important class of research methods that compare favorably with empirical experiments. It draws on Popper’s demarcation between science and non-science (Conjectures and refutations: the growth of scientific knowledge. Routledge, London, 1992) and Epstein’s principle of generative explanation (Generative social science: studies in agent-based computational modeling. Princeton University Press, Princeton, NJ, 2006) to show how simulated experiments can falsify theory. The paper compares simulated and empirical experiments and shows that simulations have strengths that empirical methods lack, but they also have important relative weaknesses. We identify three threats to internal validity and two forms of external validity peculiar to simulated experiments. The paper also looks at the problem of validating simulations with crime data and suggests that simulations need to mimic the error production processes involved in the creation of empirical data. It concludes by listing ways simulations can be used to improve empirical experiments and discussing the differing operating assumption of empirical and simulation experimentalists.

Evidentiary Standards for Forensic Anthropology*

Abstract: As issues of professional standards and error rates continue to be addressed in the courts, forensic anthropologists should be proactive by developing and adhering to professional standards of best practice. There has been recent increased awareness and interest in critically assessing some of the techniques used by forensic anthropologists, but issues such as validation, error rates, and professional standards have seldom been addressed. Here we explore the legal impetus for this trend and identify areas where we can improve regarding these issues. We also discuss the recent formation of a Scientific Working Group for Forensic Anthropology (SWGANTH), which was created with the purposes of encouraging discourse among anthropologists and developing and disseminating consensus guidelines for the practice of forensic anthropology. We believe it is possible and advisable for anthropologists to seek and espouse research and methodological techniques that meet higher standards to ensure quality and consistency in our field.     

Defendant and juror race in a necessity case: An ultimate attribution error

This study investigated whether Black and White mock jurors would commit the ultimate attribution error (i.e., over-rely on dispositional explanations to understand the negative actions of out-group members) in a necessity defense case. Participants (N = 97) read a fictional looting case, in which the race of the defendant varied. Mock jurors were expected to show out-group severity through more guilty verdicts and blame attributions. Mock juror and defendant race were not significantly related to verdicts, but for the Black defendant, White mock jurors attributed more control to him, and believed he was likely to reoffend more so than did Black mock jurors. This study adds to the literature on the mechanism by which racial bias interferes with juror decisions.     

数额认识错误初论

数额认识错误,是指行为人对表现为货币或财物的行为对象的经济价值量的认识错误,即行为人主观上认识到的行为对象的经济价值与实际经济价值的不一致。从本质上看,它并不是一种独立的错误类型,而是属于事实错误中的对象认识错误。是否属于数额认识错误,应当依据法定符合说进行判断。行为人对行为对象数额的认识错误超出构成要件所要求的限度,就会影响到故意的成立以及行为人的刑事责任。     

The Examination of Commercial Printing Defects to Assess Common Origin,Batch Variation,and Error Rate*

Abstract: The examination of printing defects, or imperfections, found on printed or copied documents has been recognized as a generally accepted approach for linking questioned documents to a common source. This research paper will highlight the results from two mutually exclusive studies. The first involved the examination and characterization of printing defects found in a controlled production run of 500,000 envelopes bearing text and images. It was concluded that printing defects are random occurrences and that morphological differences can be used to identify variations within the same production batch. The second part incorporated a blind study to assess the error rate of associating randomly selected envelopes from different retail locations to a known source. The examination was based on the comparison of printing defects in the security patterns found in some envelopes. The results demonstrated that it is possible to associate envelopes to a common origin with a 0% error rate.     

Medical negligence in drug associated deaths

According to epidemiological studies adverse drug events are one of the most frequently encountered complications during medical treatment, a leading cause of hospitalisation and frequent cause of death. However, medical malpractice claims due to medication errors seem to be relatively rare. Based on a retrospective multicentre study on medical malpractice cases with lethal outcome (n = 4450), drug related cases (n = 575) were further evaluated. In 50% of cases a causal connection between drug therapy and death could be ruled out already after autopsy. In 232 cases a causal connection between drug therapy and death could be approved (drug allergies, relative overdose, wrong application, mix-up of drugs and sepsis after injection abscess). However, within the legal context only in 70 cases a medication error was approved which was in 42 cases causal for death, in 28 not. Administration of contraindicated drugs, incorrect application and relative overdose in renal insufficiency are the prevalent mistakes. Concerning the frequency of ADE in epidemiological studies medication errors are underreported in all data sources on medical malpractice; this seems to be due to the fact that even doctors and attending physicians rarely recognize an ADE; furthermore approving the connection between drug effect and death is extremely difficult for the expert witness.     

The use of error rates to predict and characterize the efficacy of presumptive field tests

From a forensic perspective, a presumptive test, one which indicates the presence or absence of a certain target material such as blood, is an invaluable tool. Among these tests, there are different specificities, sensitivities, and shelf lives. The accuracy of a test is an algebraic combination of the specificity and sensitivity of the test. Each test has limitations as given by its false positive and false negative rates. The aim of this study was to illustrate how the false positive and false negative rates are to be properly determined using a simulation study for the phenolphthalein test. New presumptive tests must be properly evaluated/validated through testing of commonly encountered household items and other potentially probative items usually found at crime scenes, however, the makeup of test sets must appropriately capture all error rates. In order to correctly use these results when the test is applied to an unknown sample recovered at a crime scene, the error rates cannot be applied directly to estimate whether or not the sample is actually the analyte of interest. In a validation study, the forensic scientist calculates the false positive rate as the p(Positive Reaction|Blood), whereas at the scene, the crime scene investigator wishes to determine the p(Blood|Positive Reaction). All crime scene investigators need to ensure that the conditional is not transposed when interpreting such results. Furthermore, this work provides a model for the assessment of a multiple test diagnostic system intended for investigators.     

Analysis of histomorphometric variables: Proposal and validation of osteon definitions

Histological analysis of bone tissue has been used to explore a variety of questions relating to age-at-death, habitual behaviors, health, and nutritional stress. Identification of intact and fragmentary osteons is of key interest to many researchers in these studies, yet the definitions of these features vary between researchers making cross-study comparisons problematic. Furthermore, histological variable definitions are often ambiguous or require subjective classifications by the observer. As a result, and as indicated by previous studies, observer error and misclassification of certain variables, namely intact and fragmentary osteons, can be significant. This study proposes new definitions for intact and fragmentary osteons that are designed to limit observer subjectivity and also explore efficacy of combining osteon types into one variable. A sample of 30 6th rib cross-sections from a modern forensic population was used to test the validity of the proposed definitions. Observations of intact osteon population density (OPD(I)) and fragmentary osteon population density (OPD(F)) were made by three observers for each cross-section. These observations were used to explore the interobserver error associated with the proposed definitions and determine if combining variables into one variable (OPD) mitigates persisting classification difficulties. Results indicate that the proposed definitions significantly reduce interobserver error and misclassification of intact and fragmentary osteons. However, the interobserver error associated with fragmentary osteons is still high. Evaluation of the variables independently indicates that combining variables has potential to reduce the predictive strength of an age estimation model and the ability to interpret age-related bone remodeling.     

Addressing the National Academy of Sciences' challenge: a method for statistical pattern comparison of striated tool marks

In February 2009, the National Academy of Sciences published a report entitled "Strengthening Forensic Science in the United States: A Path Forward." The report notes research studies must be performed to "…understand the reliability and repeatability…" of comparison methods commonly used in forensic science. Numerical classification methods have the ability to assign objective quantitative measures to these words. In this study, reproducible sets of ideal striation patterns were made with nine slotted screwdrivers, encoded into high-dimensional feature vectors, and subjected to multiple statistical pattern recognition methods. The specific methods employed were chosen because of their long peer-reviewed track records, widespread successful use for both industry and academic applications, rely on few assumptions on the data's underlying distribution, can be accompanied by standard confidence levels, and are falsifiable. For PLS-DA, correct classification rates of 97% or higher were achieved by retaining only eight dimensions (8D) of data. PCA-SVM required even fewer dimensions, 4D, for the same level of performance. Finally, for the first time in forensic science, it is shown how to use conformal prediction theory to compute identifications of striation patterns at a given level of confidence.     

案例教学法在卫生法学教学实施中的误区及解决策略

案例教学法在部分院校的卫生法教学实施中取得了良好的效果,但其教学设计、教学实施及教学反思环节仍存在误区。应当在以学生为主的教学理念和重视双向交流原则的指导下,通过精选教学案例、营造良好的课堂教学氛围、规范教学步骤来完善教学设计环节,通过突出学生学习的实践性和关注案例所涉知识面的扩展来重构教学实施环节,通过重视对本次案例教学法适用的总结反思和对整门学科适用案例教学法质量的检测来关注教学反思环节。