The Influence of Wood Grain on the Bullet's Ricochet Behavior

When a bullet ricochets from wood, various parameters will influence its behavior. In this study, the influence of the wood grain on the ricochet angle (β) and deflection angle (γ) is assessed. Series of five .32 Auto bullets were fired at different angles of incidence (α) on boards of six wood types. The results confirm the previously shown effect that the mean β‐angles usually exceed α and increase when α increases. Overall, the maximum mean γ occurs when the angle of wood grain (ζ), in relation to the plane of impact, lies between 30° and 75° but differs per combination of wood and α. The results show the inclination of γ toward the left or right, depending on the bullets left or right rotation while also showing that the direction of ζ can enhance or counteract this effect considerably, especially when α is close to the critical ricochet angle.     

The quantitative methods component in social sciences curricula in view of journal content

What level of quantitative methods (or applied statistical analysis) should graduate students in the social sciences be prepared to master, if they are to be competitive in the job market? In the age of information technology, more data, in survey or other form, about any imaginable topic exist than ever before. Empirical analysis on the basis of more advanced quantitative methods becomes more common. This study takes the perspective that graduate students in the social sciences must be prepared to read a literature that makes extensive use of quantitative methods. To quantify this dimension of the literature, top journals in economics, political science, public administration, and sociology are examined for their quantitative complexity.     

What Drives the Relationship Between Early Criminal Involvement and School Dropout?

Objective

We examine the relationship between early criminal involvement and school dropout, and analyze which factors underlie this relationship, making use of administrative data from the Netherlands.

Methods

We start by determining the unconditional correlation between early criminal involvement and school dropout, using a basic ordinary least squares model. As this association is likely to be driven by different factors, we proceed by including an extensive set of observable family and individual characteristics into the estimation model. We further proceed to models that account for the influence of unobservable heterogeneity by estimating school, class, sibling and twin fixed effects.

Results

Criminal involvement is associated with an 11 percentage point higher probability of school dropout. The magnitude of this relationship decreases gradually when we account for larger shares of observed and unobserved heterogeneity. The coefficient in the same-gender twin fixed effects model indicates a 3 percentage point higher probability of school dropout, which is statistically significant at a 10 % level. We also find that the association between criminal involvement and school dropout is stronger if juveniles are involved in severe criminal activities.

Conclusions

We conclude that the observable and unobservable factors for which we account explain around 73 % of the unconditional correlation between criminal involvement and school dropout. The remaining variation likely reflects individual-specific characteristics that are different between same-gender twins. A true treatment effect, if existing, is likely to be relatively small. At the same time, serious criminal behavior appears to causally affect school dropout.

     

Regulatory delay and growth: a cross country analysis

This paper exploits cross country data on regulatory delay for 135 countries. The results from the regression analysis suggest that waiting time stemming from business procedures has a negative impact on economic growth, especially when we take into account possible endogeneity.     

Vice Laws and Self-Sovereignty

There is an important moral difference between laws that criminalize drugs and prostitution and laws that make them illegal in other ways: criminalization violates our moral rights in a way that nonlegalization does not. Criminalization is defined as follows. Drugs are criminalized when there are criminal penalties for using or possessing small quantities of drugs. Prostitution is criminalized when there are criminal penalties for selling sex. Legalization is defined as follows. Drugs are legalized when there are no criminal penalties for manufacturing, selling and possessing large quantities of drugs. Prostitution is legalized when there are no criminal penalties for owning or operating a brothel or escort service, no criminal penalties for working as a paid agent for sex work, and no criminal penalties for paying someone for sex who is above the age of legal employment and sexual consent. The criminalization of drugs and prostitution violate the right of self-sovereignty in depriving individuals of important forms of control over their own minds and bodies, but nonlegalization does not violate this right. It is therefore consistent, as a matter of principle, to advocate decriminalization but to oppose legalization.     

The implementation of Directive 2001/20/EC into Belgian law and the specific provisions on pediatric research

The European Clinical Trial Directive (2001/20/EC) was implemented into the Belgian legal system by the Law of 7 May 2004 concerning experiments on the human person (LEH). Apart from implementing the European Directive, this law also broadens the scope of the Directive from interventional clinical trials to all medical experiments involving human persons. This article offers an overview of the requirements for involving minors in medical experiments that are captured in the LEH, illustrates the process of protocol review by an ethics committee, and discusses the dissimilarities between the LEH and the European Directive.     

Family negativity and delinquent behavior in adolescence: a predictive multivariate latent growth analysis

ABSTRACT

The current study had three aims: (1) to explore whether there is over-time change in adolescent delinquency and negativity in the parent–adolescent, sibling and marital relationships during adolescence; (2) to examine the interactions of negativity across subsystems; and (3) to examine whether levels and changes in adolescent delinquency are predicted by levels and changes in negativity in all family subsystems. Data of 497 families participating in the RADAR-young study were used. Ratings of all family members were used to measure negativity in family relationships, and adolescent self-report was used for delinquency. Multivariate latent growth curve models showed over-time increases in mother-adolescent negativity and over-time decreases in sibling negativity, as well as significant individual differences in these changes. Second, evidence for both social contagion and compensatory processes in family negativity was found. Third, initial levels of parent–adolescent negativity were related to initial levels but not over-time changes of adolescent delinquency, whereas initial levels of sibling negativity were related to over-time changes but not initial levels of adolescent delinquency. Finally, increases in parent–adolescent negativity were related to faster increases in adolescent delinquency, and decreases in sibling negativity were related to slower increases in adolescent delinquency. Implications of these results are discussed.