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Abstract
A highlighted issue in long-term care (LTC) financing is the presence of unfortunate incentives in financing schemes. For instance, in Norway, a high share of high-income recipients provides financial incentives to the local governments (the agencies in charge of the LTC system) to increase reliance on nursing home care relative to community housing and home-based care. This article examines the effects of the Norwegian LTC funding system on the composition of LTC services at the local government level. I use a cross-section from 2009 of 391 local governments to estimate a fractional probit model using quasi-maximum likelihood estimation. Controlling for need and geographical variations in care costs, I find that the share of "rich" elderly has a significant association with three measures of the volume of nursing home care relative to home-based care.

AbstractThe scan statistic based on likelihood ratios (LRs) have been widely discussed for detecting spatial clusters. When developing the scan statistic, it uses the maximum likelihood estimates of the incidence rates inside and outside candidate clusters to substitute the true values in the LR statistic. However, the parameter estimation has a significant impact on the sensitivity of the scan statistic, which favors the detection of clusters in areas with large population sizes. By presenting the effects of parameter estimation on Kulldorff's scan statistic, we suggest a standardized scan statistic for spatial cluster detection. Compared to the traditional scan statistic, the standardized scan statistic can account for the varying mean and variance of the LR statistic due to inhomogeneous background population sizes. Extensive simulations have been performed to compare the power of the two cluster detection methods with known or/and estimated parameters. The simulation results show that the standardization can help alleviate the effects of parameter estimation and improve the detection of localized clusters. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012

There has been no attention to circular (purely cyclical) data in political science research. We show that such data exist and are mishandled by models that do not take into account the inherently recycling nature of some phenomenon. Clock and calendar effects are the obvious cases, but directional data are observed as well. We describe a standard maximum likelihood regression modeling framework based on the von Mises distribution, then develop a general Bayesian regression procedure for the first time, providing an easy-to-use Metropolis-Hastings sampler for this approach. Applications include a chronographic analysis of U.S. domestic terrorism and directional party preferences in a two-dimensional ideological space for German Bundestag elections. The results demonstrate the importance of circular models to handle periodic and directional data in political science.

Although convincing arguments have been put forward for continuous‐time modeling, its use in panel research is rare. In one approach, classical N = 1 state‐space modeling procedures are adapted for panel analysis to estimate the exact discrete model (EDM) by means of filter techniques. Based on earlier less satisfactory indirect methods, a more recent approach uses structural equation modeling (SEM) to get the maximum likelihood estimate of the EDM by the direct method. After an introduction into continuous‐time state‐space modeling for panel data and the EDM, a thorough comparison is made between the two distinct approaches with quite different histories by means of Monte Carlo simulation studies. The model used in the simulation studies is the damped linear oscillator with and without random subject effects.

Conservation and sustainable use of animal genetic resources was the subject of United Nation Convention from Rio de Janeiro since 1992 and International Treaty regarding phytogenetical resources for food and agriculture. In Romania, the conservation of genetic fund is scientifically accepted and applied somewhat in 1960 but at the time it has a legislative support. Survey carries out on 33 cows were followed: milk yield indices per successive lactation; body development indices at adult animals; intrapopulation genetic structure; genetic parameters. For estimating the genetic parameters has been used REML (Restricted Maximum Likelihood) method. From the productive point of view, milk yield ranges between 1493.36 kg and 2499.14 kg with variability over 28%. The average value for the size was 122.27 cm and body weight was 575.59 kg. Different studies shows average value for milk yield of 1624 kg for a mean of 216.54 days in 1947 at "Anton Paul" – Ilfov farm, 2172 kg in 1959 and 2310 kg in 1960, 1976 kg in 1963 at G.A.S Laza Vaslui, 1244 kg in 1961 at G.A.C "8 Mai" S?veni, Fete?ti. The heritability coefficient (h2) has average value between 0.30-0.34 for the fat and milk quantity, and in case of fat percentage it may notice a strong genetic determinism. The studied population represents a valuable genetic fund, which must be preserved and ameliorated in the way of mixed production meat–milk and developed numerically.

Currently, four species of the lacertid lizard genus Adolfus are known from Central and East Africa. We sequenced up to 2,825 bp of two mitochondrial (16S and cyt b) and two nuclear (c-mos and RAG1) genes from 41 samples of Adolfus (representing every species), two species each of Gastropholis and Holaspis, and in separate analyses combined this data with GenBank sequences of all other Eremiadini genera and four Lacertini outgroups. Data from DNA sequences were analyzed with maximum parsimony (PAUP), maximum-likelihood (RAxML) and Bayesian inference (MrBayes) criteria. Results demonstrated that Adolfus is not monophyletic: A. africanus (type species), A. alleni and A. jacksoni are sister taxa, whereas A. vauereselli and a new species from the Itombwe Plateau of Democratic Republic of the Congo are in a separate lineage. Holaspis and Gastropholis were recovered in separate clades. Based on this molecular data, relatively substantial sequence divergence and multiple morphological differences, we describe a new genus of lacertid for the lineage including A. vauereselli and the new Itombwe species. The recognition of this new, endemic genus underscores the conservation importance of the Albertine Rift, especially the Itombwe Plateau, a unique region that is severely threatened by unchecked deforestation, mining and poaching.

International audience ; The use of food industry by-products for feeding is restricted by the European Union (EU) by-product regulation (1774/2002). However, the actual public health risks involved in the use of such products are poorly recognized. This study focuses on bovine milk rejected at the dairy because of a positive result in antimicrobial drug testing and thereafter used as feed for finisher pigs in Finland. In theory, this current practice could expose pork consumers to antimicrobial drug residues. Raw bulk milk samples originating from rejected lots were analysed with a multiresidue method detecting five betalactams, including benzylpenicillin (BP). Based on the probabilistic simulation model developed, concentrations of BP in pork invariably remained below 1% of the maximum residue limit (MRL). Therefore the use of this by-product as feed with the current practice was considered to pose only a negligible risk to consumers of pork products.

The purpose of this monograph is to present a unified econometric framework for dealing with the issues of endogeneity in Markov-switching models and time-varying parameter models, as developed by Kim (2004, 2006, 2009), Kim and Nelson (2006), Kim et al. (2008), and Kim and Kim (2009). While Cogley and Sargent (2002), Primiceri (2005), Sims and Zha (2006), and Sims et al. (2008) consider estimation of simultaneous equations models with stochastic coefficients as a system, we deal with the LIML (limited information maximum likelihood) estimation of a single equation of interest out of a simultaneous equations model. Our main focus is on the two-step estimation procedures based on the control function approach, and we show how the problem of generated regressors can be addressed in second-step regressions

Forecasting of the manufactured appliances' reliability is a difficult and still considered issue. The article presents results of the household appliances' reliability research with the application of a modified Weibull distribution. In the first part there are shown theoretical assumptions of the research together with choice grounds of the applied model. Estimates of parameters of the model were based on a data set, which contained censored observations. This information is derived from actual observations of warranty services of a selected production company. The second part of the paper contains the results of estimates obtained using maximum likelihood methods. It also contains comments on the usefulness of the results. The study allowed to compare changes in the reliability of the selected appliances in recent years, as well as to relate them to the quality requirements — both customer and manufacturer.

We construct a density estimator and an estimator of the distribution function in the uniform deconvolution model. The estimators are based on inversion formulas and kernel estimators of the density of the observations and its derivative. Initially the inversions yield two different estimators of the density and two estimators of the distribution function. We construct asymptotically optimal convex combinations of these two estimators. We also derive pointwise asymptotic normality of the resulting estimators, the pointwise asymptotic biases and an expansion of the mean integrated squared error of the density estimator. It turns out that the pointwise limit distribution of the density estimator is the same as the pointwise limit distribution of the density estimator introduced by Groeneboom and Jongbloed (Neerlandica, 57, 2003, 136), a kernel smoothed nonparametric maximum likelihood estimator of the distribution function.

The definitive version is available at: http://www.agu.org/journals/jgr ; We used a novel method that combined probabilistic analysis and spatial modeling assisted by GIS to analyze the risk of extreme precipitation in northeast Spain related to three atmospheric circulation configurations: the North Atlantic Oscillation (NAO), the Mediterranean Oscillation, and the Western Mediterranean Oscillation (WeMO). The analysis was performed at an event-based scale using data obtained from daily atmospheric circulation indices. The maximum intensity and total precipitation magnitude recorded during positive and negative circulation events were obtained from the daily records of 174 observatories between 1950 and 2006. The series of both maximum intensity and magnitude for positive and negative phases of the three atmospheric circulation indices follow a generalized Pareto (GP) distribution. A regression-based interpolation procedure was used to generate distributed maps of GP parameters, enabling us to determine the probability of the magnitude and maximum intensity of precipitation and the quantile precipitation for any return period associated with the positive and negative phases of the three atmospheric circulation patterns. A high spatial variability in precipitation risk was found, depending on the positive/negative phases of the three atmospheric circulation patterns. Different phases of the circulation indices show contrasting effects on the two analyzed parameters. Thus the most extreme daily precipitation during winter months is expected for negative WeMO events, representing a markedly different result from those obtained for other events. In contrast, negative NAO events record the most extreme precipitation magnitude risk per event, although this is mainly restricted to mountainous areas. ; This work was supported by projects financed by the Spanish Commission of Science and Technology (CGL2005–04508/BOS and CGL2008–01189/BTE), the 7th framework program of the European Commission (projects ACQWA (FP7-ENV-2007-1-212250) and EUROGEOSS (FP7-ENV-2008-1-226487)), and the "Programa de grupos de investigación consolidados" financed by the Aragón Government. ; Peer reviewed

Gender and connectivity initiatives intended to promote development assume that the Internet can have a significant impact on the careers and lives of women. It is important to test this assumption, given the prior research that establishes the educational and organisational limitations on women in professional careers, which increase the likelihood of restricted networks. The initial quantitative research available on the impact of the Internet is based on data from 2000. It shows improved access to the Internet for both men and women, but no evidence for Internet effects on productivity or professional networking. This study employs recent qualitative data from scientists in Kerala, which modify these conclusions and provide some grounds for optimism. The domestic context, so important for women in a patrifocal society, has created conditions for change, as the interest in children's education and the presence of home computers has begun a process of 'circumvention' of gender roles that demands further study.

Fundação para a Ciência e a Tecnologia (FCT) ; ALBAN ; European Union ; FCT: SFRH/BD/47821/2008 ; European Union: E07D402597BR ; We evaluated genetic and environmental factors affecting age at first farrowing of sows in the Brazilian southeast. For this purpose, 466 observations regarding the age at first farrowing were made for Dalland-C40 (c) animals belonging to two herds. The effects of the environmental factors on this trait were assessed by means of a model that included, as random effects, the influence of the sow's father and mother and, as fixed effects, the influence the year of birth, the herd and the birth season, along with the covariable litter size at birth. The variance components were estimated using the derivative-free restricted maximum likelihood method. The estimated mean was 354.8 +/- 25.87 days, with a coefficient of variation of 7.29%. Significant effects on the trait were observed for the herd, the year and the season of birth; but a linear effect of litter size at birth on the age at first farrowing was not observed. The boar did not significantly contribute to the variation occurring among the sows, whereas the sow's mother caused significant variation. The heritability estimate for the age at first farrowing was 0.44 +/- 0.15, which is considered high. We concluded that herd effect and year and season of birth should be taken into consideration for an accurate genetic comparison; consequently, the animals should be joined into contemporary groups.

ABSTRACTIn this paper we propose ridge regression estimators for probit models since the commonly applied maximum likelihood (ML) method is sensitive to multicollinearity. An extensive Monte Carlo study is conducted where the performance of the ML method and the probit ridge regression (PRR) is investigated when the data are collinear. In the simulation study we evaluate a number of methods of estimating the ridge parameter k that have recently been developed for use in linear regression analysis. The results from the simulation study show that there is at least one group of the estimators of k that regularly has a lower mean squared error than the ML method for all different situations that have been evaluated. Finally, we show the benefit of the new method using the classical Dehejia and Wahba dataset which is based on a labour market experiment.

Sub‐Saharan African countries have traditionally lagged the rest of the developing world in terms of overall trade relative to gross domestic product. But, there is growing interest among these countries to initiate trade policies and improve quality of institutions as a way to promote trade and boost foreign direct investment. This article extends the gravity model of trade to include proxies for trade reform policy and institutional quality among the 15 countries of the Economic Community of West African States (ECOWAS) for data spanning 1984–2006. Alternative methods of estimation based on ordinary least squares, Heckman two‐step procedure, and Poisson pseudo‐maximum likelihood produce predictions that are consistent with the standard gravity model. They further highlight the evidence of restrictive trade policies and weak institutions that contribute to the failure of ECOWAS countries to boost bilateral trade. (JEL F13, F15, O19, O55)