Familicide: The killing of spouse and children

A familicide is a multiple-victim homicide incident in which the killer's spouse and one or more children are slain. National archives of Canadian and British homicides, containing 109 familicide incidents, permit some elucidation of the characteristic and epidemiology of this crime. Familicides were almost exclusively perpetrated by men, unlike other spouse-killings and other filicides. Half the familicidal men killed themselves as well, a much higher rate of suicide than among other uxoricidal or filicidal men. De facto unions were overrepresented, compared to their prevalence in the populations-at-large, but to a much lesser extent in familicides than in other uxoricides. Stepchildren were overrepresented as familicide victims, compared to their numbers in the populations-at-large, but to a much lesser extent than in other filicides; unlike killers of their genetic offspring, men who killed their stepchildren were rarely suicidal. An initial binary categorization of familicides as accusatory versus despondent is tentatively proposed. © 1995 Wiley-Liss, Inc.     

Efficacy of standard deviational ellipses in the application of criminal geographic profiling

The premise for this study is that the physical and cultural landscape has a deterministic effect on the location and distribution of serial crime. As a consequence, the distribution of linked crime scenes should exhibit a shape and orientation that is consistent with the underlying landscape. Geographic Profiling models that are able to account for these effects will provide more accurate results than those models that do not. Utilizing basic geographic principles of central tendency and spatial diffusion, this research first analyzed the output of circular and elliptical profile models generated for 30 serial burglaries (n = 164) and 67 serial robberies (n = 370) in Baltimore, Maryland between 1994 and 1997. A comparative analysis of the model output reveals that the Standard Deviational Ellipse is significantly (p = 0.000) better able to predict the home location of a serial offender than profiles generated from circles. Next, the relationship between the orientation of elliptical profiles and the mean linear orientation of the corresponding landscape was assessed to reveal a moderate but significant correlation (r = 0.511, p < 0.001). Together, these findings demonstrate that landscape does impact the locations of crime, and is a measurable parameter that can improve the efficacy of geographic profiling. Copyright © 2008 John Wiley & Sons, Ltd.     

Offender and crime characteristics of female serial arsonists in Japan

This study of Japanese female serial arsonists examined their crimes and background characteristics. The data were a sample from the national police register containing arson cases resulting in charges in Japan between 1982 and 2005. Serial arsonists were 6% of the arson offenders and 12% of these were female, resulting in 83 female serial arsonist data sets. The mean age was 37.6 years and 43% were unemployed. Nearly half were married. Only 28% had a documented history of mental problems and 22% had a prior arrest, usually for theft (19%). Female serial arsonists are characterised by going to a place near their home with a lighter and setting fire directly to combustible materials. Non‐metric multidimensional scaling was used to analyse 33 variables related to the offences. The arsons could be differentiated in terms of either expressive or instrumental sources of action. Expressive arsons were opportunistic and impulsive acts, motivated by emotional distress. The fires were mostly set close to home. Expressive arsons were characteristic of 66% of the females. Instrumental arsons were often motivated by revenge and involved planned and goal‐directed behaviours. They were committed by 13% of the females. Instrumental arsonists tended to travel further from home. Copyright © 2007 John Wiley & Sons, Ltd.     

不同运动经历人群的内隐序列学习能力

考察不同运动经历人群的内隐序列学习能力。被试为上海体育学院小球运动员和非运动员;实验结合PDP,采用序列学习任务,并测试操作智商与记忆广度。结果发现,运动员在15个组段上的平均反应时、内隐学习量、自动提取贡献率上显著大于非运动员;不同水平运动员在内隐学习量上差异显著。研究结论:运动员的内隐序列学习能力显著好于非运动员,与运动水平有关,与智商无显著相关;这种内隐序列学习能力可能是某种运动能力的表现形式。     

Reconsidering the two-second decay hypothesis in verbal working memory

A common belief in the study of short-term memory is that the verbal trace decays around two seconds after it is encoded. This belief is typically assumed to follow from the finding that in immediate serial recall, the time required to rapidly articulate a span-length list is around two seconds. Empirically, this belief is in opposition to a broad set of findings across a number of domains that establish mean decay times to be longer than two seconds. Theoretically, the available computational and mathematical models of immediate serial recall do not address this issue directly, because they typically rely on other mechanisms in addition to decay to account for forgetting. As such, they may show that decay times can be longer than two seconds, but they fail to show that they cannot be as short as two seconds. We address the issue directly and set a lower bound on mean trace decay times, even under the limiting assumption that all forgetting is due to trace decay. We do this by presenting a simple item-based model of trace decay that allows us to estimate values of mean trace duration. For a set of words whose span-length lists can be rapidly articulated in about two seconds, the model offers a conservative estimate for their mean decay times of around four seconds. Both the experimental and theoretical evidence show that items in verbal working memory decay considerably slower than the two-second decay hypothesis claims.     

Media and violence: The case of professional football championship games

Recently much research has linked media violence with actual violence. The most serious violence, suicides, and homicides have been connected to events portrayed in the mass media. In this study I examine the effect of NFL football playoff games on the relative incidence of homicides between standard metropolitan statistical areas (SMSAs) with and without participating teams. Results show that homicides may be related to participation. Specifically, SMSAs with losing teams experience significantly more homicides than SMSAs with winning teams.     

Homicide and property crime: The relationships to anomie

Sociological explanations of crime have given considerable attention to Merton's anomie theory without systematically testing it. This paper tests Merton's theory through operationalizing anomie in terms of the degree of inequality in the distribution of income in each of the 50 states. A multiple regression analysis determines that while income inequality is significantly related to the rate of homicide, it is not significantly related to the rate of property crime. A preliminary cross-national analysis of 20 nations replicates this same general finding. The results suggest that a relatively large gap between material success and the means to success is likely to result in crimes of violence rather than property crime once we control the influence of other variables.     

Finding a serial burglar's home using distance decay and conditional origin–destination patterns: a test of empirical Bayes journey-to-crime estimation in the Hague

Can we tell where an offender lives from where he or she commits crimes? Journey-to-crime estimation is a tool that uses crime locations to tell us where to search for a serial offender's home. In this paper, we test a new method: empirical Bayes journey-to-crime estimation. It differs from previous methods because it utilises an ‘origin–destination’ rule in addition to the ‘distance decay’ rule that prior methods have used. In the new method, the profiler not only asks ‘what distances did previous offenders travel between their home and the crime scenes?’ but also ‘where did previous offenders live who offended at the locations included in the crime series I investigate right now?’. The new method could not only improve predictive accuracy, it could also reduce the traditional distinction between marauding and commuting offenders. Utilising the CrimeStat software, we apply the new method to 62 serial burglars in The Hague, The Netherlands, and show that the new method has higher predictive accuracy than methods that only exploit a distance decay rule. The new method not only improves the accuracy of predicting the homes of commuters—offenders who live outside their offending area—it also improves the search for marauders—offenders who live inside their offending area. After presenting an example of the application of the technique for prediction of a specific burglar, we discuss the limitations of the method and offer some suggestions for its future development. Copyright © 2009 John Wiley & Sons, Ltd.     

Data-driven sequence learning or search: What are the prerequisites for the generation of explicit sequence knowledge?

In incidental sequence learning situations, there is often a number of participants who can report the task-inherent sequential regularity after training. Two kinds of mechanisms for the generation of this explicit knowledge have been proposed in the literature. First, a sequence representation may become explicit when its strength reaches a certain level (Cleeremans, 2006), and secondly, explicit knowledge may emerge as the result of a search process that is triggered by unexpected events that occur during task processing and require an explanation (the unexpected-event hypothesis; Haider & Frensch, 2009). Our study aimed at systematically exploring the contribution of both mechanisms to the generation of explicit sequence knowledge in an incidental learning situation. We varied the amount of specific sequence training and inserted unexpected events into a 6-choice serial reaction time task. Results support the unexpected-event view, as the generation of explicit sequence knowledge could not be predicted by the representation strength acquired through implicit sequence learning. Rather sequence detection turned out to be more likely when participants were shifted to the fixed repeating sequence after training than when practicing one and the same fixed sequence without interruption. The behavioral effects of representation strength appear to be related to the effectiveness of unexpected changes in performance as triggers of a controlled search.     

Stimulus-dependent modulation of perceptual and motor learning in a serial reaction time task

In two experiments, we investigated the impact of spatial attributes on the representation acquired during a serial reaction time task. Two sequences were used, in which structural regularities occurred either in the horizontal or in the vertical locations of successive stimuli. After training with the dominant hand, participants were required to respond with the non-dominant hand to either the original sequence or to a mirror-ordered version of the original sequence that required finger movements homologous to those used during training. We observed that a difference in reaction times between the two transfer conditions was smaller in the vertical sequence than in the horizontal sequence. This pattern of results was independent of whether three fingers (Experiment 1) were used or only one finger (Experiment 2) was used for responding. This result suggests that perceptual and motor learning mechanisms may be weighted differently depending on the context in which the stimulus is presented.