Body Size,Skills, and Income: Evidence From 150,000 Teenage Siblings

We provide new evidence on the long-run labor market penalty of teenage overweight and obesity using unique and large-scale data on 150,000 male siblings from the Swedish military enlistment. Our empirical analysis provides four important results. First, we provide the first evidence of a large adult male labor market penalty for being overweight or obese as a teenager. Second, we replicate this result using data from the United States and the United Kingdom. Third, we note a strikingly strong within-family relationship between body size and cognitive skills/noncognitive skills. Fourth, a large part of the estimated body-size penalty reflects lower skill acquisition among overweight and obese teenagers. Taken together, these results reinforce the importance of policy combating early-life obesity in order to reduce healthcare expenditures as well as poverty and inequalities later in life.     

Do They Know What They are Doing? Risk Perceptions and Smoking Behaviour Among Swedish Teenagers

Cross-sectional survey data on Swedish adolescents aged 12–18 was used to analyse perceived risks of smoking-related lung cancer, the determinants of these risk perceptions, and how these perceptions related to smoking behaviour. Three major conclusions were drawn: (1) that both smokers and non-smokers overestimated the risks of lung cancer, (2) that these risk perceptions fell substantially with age, but nevertheless implied risk overestimation, and (3) that individuals with higher perceived risks were less likely to be smokers but that risk beliefs had no effect on the number of cigarettes smoked.     

More Large Accidents Through Complexity

Many would tend to characterize modern society as steeped in complexity. This complexity is seen by a number of professional people to imply risk-taking--or risk-making--on a high level. "A single mistake may give consequences of quite different proportions from earlier times," as one critic puts it. This hypothesis of increasing risks on a high level--of worst things getting worse--has been tested on fires in Sweden. Fire has always been a powerfully upsetting agent to the social fabric. Today industrial fires dominate the picture economically. The cost of industrial fires is about three times the cost of residential fires in Sweden. It is of interest to note that the damage cost of the worst fires (as measured in insurance payments) does not form an increasing part of overall fire damage costs, as one would expect from the above hypothesis. Whether the hypothesis holds with regard to indirect costs due to production stand-still is more uncertain. We can conclude that the potential of complexity to create large abnormal occurrences may have been somewhat prematurely announced--at least with regard to fires in Sweden.     

Parameter estimation for partially observed hypoelliptic diffusions

Summary.  Hypoelliptic diffusion processes can be used to model a variety of phenomena in applications ranging from molecular dynamics to audio signal analysis. We study parameter estimation for such processes in situations where we observe some components of the solution at discrete times. Since exact likelihoods for the transition densities are typically not known, approximations are used that are expected to work well in the limit of small intersample times Δ t and large total observation times N  Δ t . Hypoellipticity together with partial observation leads to ill conditioning requiring a judicious combination of approximate likelihoods for the various parameters to be estimated. We combine these in a deterministic scan Gibbs sampler alternating between missing data in the unobserved solution components, and parameters. Numerical experiments illustrate asymptotic consistency of the method when applied to simulated data. The paper concludes with an application of the Gibbs sampler to molecular dynamics data.     

Parental transfers, student achievement, and the labor supply of college students

Using nationally representative data from the NLSY97 and a simultaneous equations model, this paper analyzes the financial motivations for and the effects of employment on U.S. college students’ academic performance. The data confirm the predictions of the theoretical model that lower parental transfers and greater costs of attending college increase the number of hours students work while in school, although students are not very responsive to these financial motivations. They also provide some evidence that greater hours of work lead to lower grade point averages (GPAs).     

Monitoring Trends in Global Combat: A New Dataset of Battle Deaths

Both academic publications and public media often make inappropriate use of incommensurate conflict statistics, creating misleading impressions about patterns in global warfare. This article clarifies the distinction between combatant deaths, battle deaths, and war deaths. A new dataset of battle deaths in armed conflict is presented for the period 1946–2002. Global battle deaths have been decreasing over most of this period, mainly due to a decline in interstate and internationalised civil armed conflict. It is far more difficult to accurately assess the number of war deaths in conflicts both past and present. But there are compelling reasons to believe that there is a need for increased attention to non-battle causes of mortality, especially displacement and disease in conflict studies. Therefore, it is demographers, public health specialists, and epidemiologists who can best describe the true human cost of many recent armed conflicts and assess the actions necessary to reduce that toll.     

Personal assistance—direct payments or alternative public service. Does it matter for the promotion of user control?

Personal assistance organised as direct payments is seen as an important means for securing user control and freeing disabled people from their reliance on welfare professionals and unpaid carers. The hypothesis put forward in the article is that just looking at whether personal assistance is organised as direct payments or as an alternative service represents an overly restricted approach to judge how the user’s preferences are taken care of. By comparing models of personal assistance in the US, the UK, Sweden and Norway it will show that several other factors influence user control. In the final part of the article the question is raised as to whether paternalism is always negative for welfare service users. Since the users constitute a broad group it might be questioned if the assumption of the service users as rational, well informed and competent to make the best choices is always valid.     

The Use of Replicates in Logistic Measurement Error Modelling

The use of replicates is essential in logistic measurement error models with random, additive error, as it gives a consistent estimate of the variance of the measurement error. In this paper, we investigate two different aspects of the use of replicates. We look into the efficiency gain in using more than two replicates in situations where the replicates are correlated. We find that, unlike the situation with independent replicates, the efficiency gain is an almost linear function of the number of replicates. Further, we study the allocation of replicates among study subjects, and find that the optimal way of doing this is to allocate few replicates to as many subjects as possible, rather than allocating many replicates to fewer subjects.