Pre-school immunisation: the importance of achieving adequate uptake

SUMMARY. With the anticipated introduction of a triple vaccine that protects against measles, mumps and rubella, the proportion of children vaccinated each year will need to rise from 68 per cent to 95 per cent if the target of eliminating measles is to be achieved. This article reviews the morbidity associated with preventable infectious diseases of childhood, discusses possible reasons for inadequate vaccine uptake and suggests ways for improving this situation including the case for school entry legislation.     

Parameter Estimation in Pair-hidden Markov Models

Abstract.  This paper deals with parameter estimation in pair-hidden Markov models. We first provide a rigorous formalism for these models and discuss possible definitions of likelihoods. The model is biologically motivated and therefore naturally leads to restrictions on the parameter space. Existence of two different information divergence rates is established and a divergence property is shown under additional assumptions. This yields consistency for the parameter in parametrization schemes for which the divergence property holds. Simulations illustrate different cases which are not covered by our results.     

Estimating the Incidence of Hidden,Untreated Opiate Use

Illegal drug use is a hidden phenomenon, making it extremely difficult to obtain accurate estimates of untreated use. Yet it is this very estimate of incidence that is required by policy makers and service providers who are responsible for allocating increasingly scarce resources in times of worldwide recession. Using Irish data on more than 6,000 cases of clients presenting for first treatment, a Gamma incubation period distribution describing progression to first opiate treatment is fitted. An analytical solution of the back calculation method and a linear Volterra integral equation are used to project back and estimate the hidden, untreated population of opiate users.     

THE STATE STREET MILE: AGE AND GENDER DIFFERENCES IN COMPETITION AVERSION IN THE FIELD

Gender differences in “competitiveness,” previously documented in laboratory experiments, are hypothesized to play a role in a wide array of economic outcomes. This paper provides evidence of competition aversion in a natural setting somewhere between the simplicity of a laboratory experiment and the full complexity and ambiguity of a labor market. The “State Street Mile” race offers both male and female participants a choice between two different levels of competition. Large, systematic age and gender differences are observed in the relationship between true ability and the decision to enter the more competitive race. Overall, qualified women and older runners are far less likely than qualified young men to enter a competitive race with prizes. However, the fastest young women unanimously enter the competitive race. Therefore, while we confirm age and gender differences in competitiveness in our field setting, the economic consequences to capable young women are rather small. (JEL J1, J7, M5)     

Packaging Protest: Media Coverage of Indigenous People's Collective Action

Indigenous peoples in Canada have engaged in hundreds of collective action events. Drawing on the news as organization and collective action literatures, we conduct a systematic examination of coverage across events, and we assess the factors associated with the number of articles, front page placement, and the inclusion of photographs. We find that increasing the size and the length of an event does not improve coverage. The latter is determined exclusively by the form of the event, and it is disruptive tactics alone that increase front page coverage. The inclusion of pictures, however, is largely determined by media news routines rather than by activists tactics.     

On the Optimality of Multivariate S‐Estimators

Abstract. In this article, we maximize the efficiency of a multivariate S‐estimator under a constraint on the breakdown point. In the linear regression model, it is known that the highest possible efficiency of a maximum breakdown S‐estimator is bounded above by 33 per cent for Gaussian errors. We prove the surprising result that in dimensions larger than one, the efficiency of a maximum breakdown S‐estimator of location and scatter can get arbitrarily close to 100 per cent, by an appropriate selection of the loss function.     

A DYNAMIC EXPLANATION OF THE WILLINGNESS TO PAY AND WILLINGNESS TO ACCEPT DISPARITY

Recent evidence from laboratory experiments suggests that important disparities exist between willingness to pay (WTP) and compensation demanded for the same good. Because a fundamental postulate in neoclassical theory is that with small income effects and many available substitutes, the willingness to accept (WTA) and WTP measures of value for a commodity should be roughly equivalent, this finding has vast implications in both a positive and normative sense. This study advances, and experimentally tests, a new explanation of the WTP/WTA disparity—a dynamic theory based on the presence of commitment costs. Although to date neoclassical models have not explained the observed data patterns well, we find that the commitment cost theory combined with a simple behavioral anomaly is able to lend insights into the causes and severity of the WTA/WTP disparity. Furthermore, we find that market experience attenuates the behavioral anomaly, consistent with the notion that no value disparity exists for agents with sufficient market experience. (JEL Q21, Q26)