L p –Estimators as Estimates of a Parameter of Location for a Sharp–pointed Symmetric Density

We study the asymptotics of L _p estimators, p > 0, over a sample having a symmetric density with a sharp–point at the centre of symmetry of the distribution. The rates of convergence of the L _p estimators in this situation depend on p and on the shape of the density. To obtain some of the limit distributions, we present new results in the asymptotics of M–estimators. We extend the delta method to the case when the Euclidean norm of the conveniently normalized M–estimators converge to a power of the Euclidean norm of a (possibly Gaussian) stable distribution.     

The Effects of Praising Qualifying Autoclitics on the Frequency of Reading

In the current study, tacts with positive qualifying autoclitics for reading were reinforced in order to determine if this procedure would increase the time spent reading by participants. Participants included 5 children, between 9–10 years old. Participants were individually exposed to 4 free operant sessions during which they were instructed to independently choose play activities. During pre- and post-treatment conditions, no consequences were provided for choosing reading. In addition, 4 treatment sessions were conducted on days separate from the free operant session days, during which the experimenter praised each positive reading-related statement emitted by the participant. Following treatment sessions, 4 out of 5 participants increased the time allocated to reading, suggesting that reading could be increased when praise is delivered contingent upon positive reading-related verbalizations.     

Mexican American Challenge to a Sacred Cow,by Deluvina Hernandez. Aztlan Publications,Chicano Studies Center,University of California,Los Angeles, 1970. 60 Pages

This study explored the attitudes of MSW students (N?=?147) toward transracial adoption and included an investigation of the students' personal experiences that may affect their attitudes. Statistical analyses revealed that although the majority of students supported the practice of transracial adoption, a number of students gave neutral responses to several items related to transracially adopted children's ethnic identity, likely indicating a lack of awareness of the consequences of transracial adoption. White students were more likely than students of other racial groups to support the practice of transracial adoption. Personal experiences, such as dating interracially and supporting interracial dating, appeared to affect students' attitudes toward transracial adoption. Limitations and implications for social work education and research are discussed.     

Out-of-sample forecast errors in misspecific perturbed long memory processes

In this paper we examine the relative increase in mean square forecast error fro fitting a weakly stationary process to the series of interest when in fact the true model is a so-called perturbed long-memory process recently introduced by Granger and Marmol (1997). This model has the property of being unidentifiable from a white noise process on the basis of the correlogram and the usual rule-of-thumbs in the Box-Jenkins methodology. We prove that this kind of missspecification can lead to serious errors in terms of forecasting. We also show that corrections based on the AR(1) model can in some cases partially solve the problem. Received: March 15, 1999; revised version: February 14, 2000     

Strong formulation for the spot 5 daily photograph scheduling problem

Earth observation satellites, such as the SPOT 5, take photographs of the earth according to consumers’ demands. Obtaining a good schedule for the photographs is a combinatorial optimization problem known in the literature as the daily photograph scheduling problem (DPSP). The DPSP consists of selecting a subset of photographs, from a set of candidates, to different cameras, maximizing a profit function and satisfying a large number of constraints. Commercial solvers, with standard integer programming formulations, are not able to solve some DPSP real instances available in the literature. In this paper we present a strengthened formulation for the DPSP, based on valid inequalities arising in node packing and 3-regular independence system polyhedra. This formulation was able, with a commercial solver, to solve to optimality all those instances in a short computation time.     

Delta Method,Moment Convergence,and Inference

Statistics, as functions of the observations, are usually given by well-behaved functions. This fact is used to obtain limit distributions for statistics whose components are given by asymptotically linear functions. These results are then extended to the moments of distributions, covariance matrices and confidence regions for parameters of interest. These regions may be used to test, through duality, hypothesis on these parameters. A theoretical application is presented.     

Importance of the prior mass for agreement between frequentist and Bayesian approaches in the two-sided test

We study distributional properties of generalized order statistics (gos) related by a random shift or scaling scheme in the continuous and discrete case, respectively. In the continuous case, we obtain new characterizations of distributions relating non-neighbouring gos extending some results given in the literature for the neighbouring cases. On the other hand, in the discrete case, we investigate the existence and uniqueness of a discrete parent distribution supported on the integers whose gos are related by a random translation.     

Spain’s Persistent Negative Educational Gradient in Fertility

European Journal of Population - A trend towards a reversal of the negative educational gradient in fertility has been detected in some advanced societies, although the end of this inverse...     

SOCIAL HIERARCHIES: A LABORATORY STUDY ON PUNISHMENT PATTERNS ACROSS NETWORKS

We experimentally study punishment patterns across network structures, and their effect on cooperation. In a repeated public goods setting, subjects can only observe and punish their neighbors. Centralized structures (like the star network) outperform other incomplete networks and reach contribution levels like the ones observed in a complete network. Our results suggest that hierarchical network structures with a commonly observed player benefit more from sanctions not because central players punish more, but because they follow, and promote, different punishment patterns. While quasi-central players in other incomplete architectures (like the line network) retaliate, and get trapped in the vicious circle of antisocial punishment, central players in the star network do not punish back, increase their contributions when sanctioned by peripheral players, and sanction other participants in a prosocial manner. Our results illustrate recent field studies on the evolutionary prevalence of hierarchical networks. We document a network-based rationale for this positive effect in an identity-free, fully anonymous environment. (JEL C72, C91, C92, D90, H41)     

When implicit prejudice does not predict explicit prejudice: Spanish version of the Concern with Acting Prejudiced scale / Cuando el prejuicio implícito no predice el explícito: versión española de la escala Concern with Acting Prejudiced

The aim of this research was to adapt and validate the Concern with Acting Prejudiced (CAP) scale for a Spanish sample. This measure evaluates concern about appearing prejudiced to others or oneself and the motivation not to deviate from personal egalitarian standards. First, we completed the translation and an item content validity analysis. Then, in Study 1 (N = 198), we conducted an exploratory factor analysis. In Study 2 (N = 383), we conducted a confirmatory analysis of the unifactorial structure of the Spanish version of the scale and examined its validity. In Study 3 (N = 89), we explored the moderating role of participants’ concern with acting prejudiced in the relation between implicit prejudice and explicit prejudice. The results confirmed the unifactorial structure of the scale, its appropriate psychometric properties and its predictive validity. Moreover, we confirmed that the CAP moderated the relation between implicit and explicit prejudice. In participants with a low concern with acting prejudiced, implicit prejudice was positively related with modern prejudice; in participants with a high concern with acting prejudiced, these variables were not related.