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111.
We revisit the sequential search problem by Hey (J Econ Behav Organ 8:137–144, 1987). In a 2 \(\times \) 2 factorial design, varying fixed and random cost treatments with and without recall, we address open research questions that were originally stated by Hey (1987). Our results provide clear evidence for Hey’s (1987) conjecture that recall negatively affects performance in sequential search. With experience, however, search behavior with and without recall converges toward the optimal reservation rule. We further find that the utilization of optimal reservation rules is independent from the stochastic nature of the search cost.  相似文献   
112.
In this article, the authors first obtain the exact distribution of the logarithm of the product of independent generalized Gamma r.v.’s (random variables) in the form of a Generalized Integer Gamma distribution of infinite depth, where all the rate and shape parameters are well identified. Then, by a routine transformation, simple and manageable expressions for the exact distribution of the product of independent generalized Gamma r.v.’s are derived. The method used also enables us to obtain quite easily very accurate, manageable and simple near-exact distributions in the form of Generalized Near-Integer Gamma distributions. Numerical studies are carried out to assess the precision of different approximations to the exact distribution and they show the high accuracy of the approximations provided by the near-exact distributions. As particular cases of the exact distributions obtained we have the distribution of the product of independent Gamma, Weibull, Frechet, Maxwell-Boltzman, Half-Normal, Rayleigh, and Exponential distributions, as well as the exact distribution of the generalized variance, the exact distribution of discriminants or Vandermonde determinants and the exact distribution of any linear combination of generalized Gumbel distributions, as well as yet the distribution of the product of any power of the absolute value of independent Normal r.v.’s.  相似文献   
113.
In measuring human development, one of the main concerns relates to the inclusion of a measure that penalizes inequalities in the distribution of achievements across the population. Using indicators from nationally representative household surveys and census data, this paper proposes a straightforward methodology to estimate a household-based distribution-sensitive human development index aggregated through generalized means. The evidence shows that the losses in human development due to inequality reach up 22, 29 and 57% in Mexico, Peru and Nicaragua, respectively. Among dimensions, the loss in the income index reaches up 61% in Nicaragua, while the education index appears as the most sensitive in the case of Mexico and Peru, with a percentage of loss between 38 and 48%. The importance of household-level calculations is highlighted when we compare the indices computed from the entire distribution with those existing indices computed for quintiles of the distribution, which minimizes the losses due to inequality. Overall, the estimations evidence a higher sensitivity of the index to inequality, and therefore an important space for public action to reduce inequality that could involve positive development returns.  相似文献   
114.
Young adults leave their parents' homes at a higher rate in Northern Europe or in the United States than in Southern Europe, with broad implications on labor market mobility and on fertility. We assess if differences in household formation are associated to differences in access to credit by estimating the impact of the cost of a mortgage on the probability that a young adult leaves his or her parents' home. Exogenous changes in the cost of credit are identified using the reform in 1998 and the cancellation in 2002 of Crédito Bonificado, a Portuguese program that provided four different reductions of the interest rate of mortgages signed by low‐ and medium‐income youth. Using a unique data set that links administrative records of debt with the 1998–2004 waves of the Employment Survey, we document three findings. First, borrowing among young adults fell when borrowing costs increased. Second, the elasticity of new household formation with respect to net interest rates lies between −0.8 and −3.3. Third, young adults responded to the increase in mortgage costs by delaying home purchases or by reducing the quality of housing services purchased, but there was only a modest increase of the probability of renting a new accommodation. (JEL: D91, H24, J13)  相似文献   
115.
Therapeutic residential care (TRC) is the name given to specialized children's homes for treating cases with severe emotional and behavioural problems that have been placed in residential care. A recent international review has revealed great diversity in the referral criteria of cases and in the models of intervention carried out. The goal of this study is to describe the population treated in these types of facilities in Spain and the therapeutic coverage given. The sample is made up of 215 young people in children's homes, of whom 93 are in TRC. The cases referred to TRC have been in residential care for less time but have gone through a greater number of placements. These young people also exhibit more problems of drug use, and there is a larger percentage of clinical‐range cases in the Child Behaviour Checklist scales of attention problems and aggressive behaviour. Nevertheless, the results of logistic regression indicate that the only variables that significantly increase the probability of being referred to TRC are drug use and changes of care placements. With regard to therapeutic care, there is a higher percentage in the TRC group receiving psychiatric care, and the sessions are also more frequent.  相似文献   
116.
This article proposes wild and the independent and identically distibuted (i.i.d.) parametric bootstrap implementations of the time-varying cointegration test of Bierens and Martins (2010 Bierens, H. J., Martins, L. F. (2010). Time varying cointegration. Econometric Theory 26:14531490.[Crossref], [Web of Science ®] [Google Scholar]). The bootstrap statistics and the original likelihood ratio test share the same first-order asymptotic null distribution. Monte Carlo results suggest that the bootstrap approximation to the finite-sample distribution is very accurate, in particular for the wild bootstrap case. The tests are applied to study the purchasing power parity hypothesis for twelve Organisation for Economic Cooperation and Development (OECD) countries and we only find evidence of a constant long-term equilibrium for the U.S.–U.K. relationship.  相似文献   
117.
In the context of local interpolators, radial basis functions (RBFs) are known to reduce the computational time by using a subset of the data for prediction purposes. In this paper, we propose a new distance-based spatial RBFs method which allows modeling spatial continuous random variables. The trend is incorporated into a RBF according to a detrending procedure with mixed variables, among which we may have categorical variables. In order to evaluate the efficiency of the proposed method, a simulation study is carried out for a variety of practical scenarios for five distinct RBFs, incorporating principal coordinates. Finally, the proposed method is illustrated with an application of prediction of calcium concentration measured at a depth of 0–20 cm in Brazil, selecting the smoothing parameter by cross-validation.  相似文献   
118.
In this article, we outline a simple and intuitively appealing procedure to derive default priors. The main idea is to regard the choice of such a prior as a formal Bayesian decision problem. We also discuss Jeffreys prior and more generally the reference prior of Bernardo (J R Stat Soc B 41:113–147, 1979) from this standpoint.  相似文献   
119.
We study the convergence of weighted sums of associated random variables. The convergence for the typical n1/p normalization is proved assuming finiteness of moments somewhat larger than p, but still smaller than 2, together with suitable control on the covariance structure described by a truncation that generates covariances that do not grow too quickly. We also consider normalizations of the form n1/qlog1/γn, where q is now linked with the properties of the weighting sequence. We prove the convergence under a moment assumption than is weaker that the usual existence of the moment-generating function. Our results extend analogous characterizations known for sums of independent or negatively dependent random variables.  相似文献   
120.
Abstract

Recently, the topics of community service activity and civic engagement relative to psychosocial benefits have received considerable attention. The current study addresses the relationship between community service activities, interethnic attitudes and individual perceptions of the value, relevance and importance of community service activities. We hypothesized that as subjects (n=40) participated in a variety of community service related activities, their perception of the overall importance of community engagement and interethnic attitudes (i.e., reductions in ethnocentrism) would significantly increase. A paired-samples t test showed significant increases among topics addressing perceptions of the importance of community service work and improvements among interethnic attitudes (p<.007). Results of the study and suggestions for future research are offered.  相似文献   
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