Why the Linear Utility Function is a Risky Choice in Discrete-Choice Experiments

This article assesses how the form of the utility function in discrete-choice experiments (DCEs) affects estimates of willingness-to-pay (WTP). The utility function is usually assumed to be linear in its attributes. Non-linearities, in the guise of interactions and higher-order terms, are applied only rather ad hoc. This paper sheds some light on this issue by showing that the linear utility function can be a risky choice in DCEs. For this purpose, a DCE conducted in Switzerland to assess preferences for statutory social health insurance is estimated in two ways: first, using a linear utility function; and second, using a non-linear utility function specified according to model specification rules from the econometrics and statistics literature. The results show that not only does the non-linear function outperform the linear specification with regard to goodness-of-fit, but it also generates significantly different WTP. Hence, the functional form of the utility function may have significant impact on estimated WTP. In order to produce unbiased estimates of preferences and to make adequate decisions based on DCEs, the form of the utility function should become more prominent in future experiments.Discrete-Choice Experiment, Preference Measurement, Health Insurance, Model Specification

A Pharmaceutical Innovation – Is it Worth the Money? Whose Money?

This study seeks to provide evidence for deciding whether or not a pharmaceutical innovation should be included in the benefit list of social health insurance. A discrete choice experiment (DCE) was conducted in Germany to measure preferences for modern insulin therapy. Of the 1,100 individuals interviewed in 2007, 200 suffered from type 1 diabetes, 150 from insulin-treated type 2 diabetes, and 150 from insulin-naive type 2 diabetes. The long-acting insulin analogue ”Insulin Detemir” is compared to human insulin as the status quo. The DCE contains two price attributes, copayment and increased contributions to health insurance. As one would expect, non-affected non-diabetics and insulin-naive diabetics exhibit higher willingness-to-pay (WTP) values through copayment (adjusted for probability of contracting diabetes), while affected type 1 and insulin-treated type 2 diabetics have higher WTP through increased contributions. However, WTP values exceed the extra treatment cost in both financing alternatives, justifying inclusion of the innovation in the benefit list from a cost-benefit point of view.Health insurance, discrete-choice experiment, preferences, diabetes

Fine Tuning of Health Insurance Regulation: Unhealthy Consequences for an Individual Insurer

This paper sheds light on some unexpected consequences of health insurance regulation that may pose a big challenge to insurers’ risk management. Because mandated uniform contributions to health insurance trigger risk selection efforts risk adjustment (RA) schemes become necessary. A good deal of research into the optimal RA formula has been performed (Ellis and Van de Ven [2000]). A recent proposal has been to add ”Hospitalization exceeding three days during the previous year” as an indicator of high risk (Beck et al. [2006]). Applying the new formula to an individual Swiss health insurer, its payments into the RA scheme are postdicted to explode, reaching up to 13 percent of premium income. Its mistake had been to successfully implement Managed Care, resulting in low rates of hospitalization. The predicted risk management response is to extend hospital stays beyond three days, contrary to stated policy objectives also of the United States.Health insurance, regulation, risk adjustment, risk management

Veracruz y el comercio de harinas en el Caribe español, 1760-1830

A través del análisis de estadísticas fiscales y tablas consulares, el autor intenta establecer la importancia que el comercio de harinas tuvo para la ciudad de Veracruz y el Virreinato de Nueva España. Mientras que para la primera fue un renglón económico importante hasta 1812, para el segundo se manifiesta de escasa relevancia durante todo el periodo. El motivo, la\ud falta de competitividad frente a harinas foráneas, derivada del obsoleto sistema de producción y las malas comunicaciones internas entre altiplano y puerto.By means of fiscal statistics analysis and\ud consular charts, the author attempts to establish a thesis based on Importance of the wheat trade and the impact of such on the development of VeraCruz and the Viceroyalty of New Spain. While for the first it was an important economic\ud incentive until 1812, for the second it manifests itself as utterly insignificant throughout the entire period.The principal reason: lack of commercial threat from the local market, suffering from inadequate farming techniques and decrepit transportation system that linked the\ud Altiplano(High Plateau) and the Harbor

Connection availability analysis of span-restorable mesh networks

Dual-span failures are the key factor of the system unavailability in a mesh-restorable network with full restorability of single-span failures. Availability analysis based on reliability block diagrams is not suitable to describe failures of mesh-restorable networks with widely distributed and interdependent spare capacities. Therefore, a new concept of restoration-aware connection availability is proposed to facilitate the analysis. Specific models of span-oriented schemes are built and analyzed. By using the proposed computation method and presuming dual-span failures to be the only failure mode, we can exactly calculate the average connection unavailability with an arbitrary allocation rule for spare capacity and no knowledge of any restoration details, or the unavailability of a specific connection with known restoration details. Network performance with respect to connection unavailability, traffic loss, spare capacity consumption, and dual failure restorability is investigated in a case study for an optical span-restorable long-haul networ

Critical incidents in paediatric critical care: who is at risk?

We evaluated the characteristics of children for whom critical incidents (CIs) were reported by performing prospective collection of patient data and retrospective review of reported CIs in a multidisciplinary neonatal-paediatric intensive care unit of a tertiary care university children's hospital. A period of 1year was analysed (January to December 2007; 1,251 admissions). CIs comprised adverse events (actual patient injury), as well as near-misses. The report form of critical incidents was web-based and reporting was voluntary, anonymous and non-punitive. The severity of all CIs was divided into minor, moderate and major. Patients with and without CIs were compared regarding the following characteristics: Paediatric Index of Mortality (PIM2), duration of mechanical ventilation, length of stay in the intensive care, admission mode (surgery, cardiopulmonary bypass, cardiac/non-cardiac unit), age and sex. There were 360 CI reports (83 per 1,000 patient days; 13% major, 26% moderate, 61% minor severity). Of these, 310 CIs could be assigned to 198 specific patients. In the univariate analysis, patient-related risk factors for CIs were higher PIM2 score (p < 0.0001), increased length of stay (p < 0.0001), mechanical ventilation (p < 0.0001), increased ventilator days (p < 0.0001), male gender (p = 0.022) and young age (p < 0.0001). Using a logistic regression model, mechanical ventilation (p < 0.0001), male gender (p = 0.034) and length of stay (p < 0.0001) continued to be associated with the occurrence of CIs. Conclusion CIs often occur in paediatric intensive care. Among the patient-related factors, male gender, mechanical ventilation, and length of stay are independently associated with CIs. Already known at admission to intensive care are male gender and, usually, requirement for mechanical ventilation. Improved knowledge of the risk factors for CIs could help to minimize their frequency and thus improve quality of car

Are immigrant children admitted to intensive care at increased risk?

These findings indicate that disparities may exist at a lower level of illness severity, due to many possible reasons (for example shortcomings in primary health care). However, once a child enters tertiary health care, nationality and socio-economic factors no longer influence quality of health care delivery

Estimation of affine transformations directly from tomographic projections in two and three dimensions

This paper presents a new approach to estimate two- and three-dimensional affine transformations from tomographic projections. Instead of estimating the deformation from the reconstructed data, we introduce a method which works directly in the projection domain, using parallel and fan beam projection geometries. We show that any affine deformation can be analytically compensated, and we develop an efficient multiscale estimation framework based on the normalized cross correlation. The accuracy of the approach is verified using simulated and experimental data, and we demonstrate that the new method needs less projection angles and has a much lower computational complexity as compared to approaches based on the standard reconstruction technique