Minimum local distance density estimation

We present a local density estimator based on first-order statistics. To estimate the density at a point, x, the original sample is divided into subsets and the average minimum sample distance to x over all such subsets is used to define the density estimate at x. The tuning parameter is thus the number of subsets instead of the typical bandwidth of kernel or histogram-based density estimators. The proposed method is similar to nearest-neighbor density estimators but it provides smoother estimates. We derive the asymptotic distribution of this minimum sample distance statistic to study globally optimal values for the number and size of the subsets. Simulations are used to illustrate and compare the convergence properties of the estimator. The results show that the method provides good estimates of a wide variety of densities without changes of the tuning parameter, and that it offers competitive convergence performance.     

ESTIMATING MARKET POWER IN HOMOGENOUS PRODUCT MARKETS USING A COMPOSED ERROR MODEL: APPLICATION TO THE CALIFORNIA ELECTRICITY MARKET

This study proposes a novel econometric approach to estimating market power in homogenous product markets. We use a composed error model to estimate the stochastic part of firms' strategic pricing equation. This part is formed by two random variables: a traditional error term, which captures random shocks, and a random conduct term, which measures the degree of market power. This approach allows for the conduct parameter to vary flexibly across firms and within firms over time, and avoids ad hoc structural restrictions for identifying firms' conduct. The empirical application of our approach is based on a well‐known California wholesale electricity market data set, which has been rigorously used to study market power. Our results suggest that realization of market power varies over both time and firms, and reject the assumption of a common or time‐invariant conduct parameter. (JEL C34, C51, L13, L94)     

Becoming a Marriage, Family and Child Counselor: Notes from a Chicano

Becoming a licensed Marriage, Family and Child Counselor (MFCC) in California is presented from a Chicano's perspective based on the author's own training. He reports that 1) there is a need for Chicanos trained extensively in marriage and family counseling to serve the large Mexican American population; 2) MFCC is a growing profession yet few Chicanos are entering it; 3) few Chicano professionals are involved in the training, teaching and supervision of marriage and family counselors; and 4) the state licensing board and the two marriage and family counselors' associations do not identify minority counselors nor those who provide Spanish speaking services .     

Do Temporary Contracts Increase Work Accidents? A Microeconometric Comparison between Italy and Spain

Abstract. This paper analyses the effect of contract type on the rate of work‐related accidents in Italy and Spain, using the 1999 Labour Force Survey ‘ad hoc module’. We find that, once personal and job characteristics of workers are controlled for, the differences in the probability of suffering a work accident between open‐ended and temporary workers vanish. Furthermore, following a novel decomposition analysis by Yun, we obtain that personal and job characteristics tend to increase the probability of having an accident for temporary workers, but the specific influence of contract type favours the latter, who show a lower probability on this account.     

Observing Tacting Increases Uninstructed Tacts in Children with Autism

The effects of observing an adult emitting tacts on children’s rate of uninstructed (i.e., “spontaneous”) tacts were examined in three children diagnosed with autism. Each participant was exposed to two conditions in four settings each: in condition 1, participants received 20 trials of teacher-initiated interactions in which the child was asked to tact 20 objects during 5 min. Condition 2 was identical to condition 1 except that the teacher also tacted 20 objects interspersed with the 20 tact trials. The number of uninstructed tacts was recorded in both conditions. Children emitted between 1.58 and 2.68 times more uninstructed tacts in condition 2 than in condition 1. These results indicate that teachers’ emission of tacts increases the emission of uninstructed tacts in children with autism.     

Analyzing Precautionary Regulation: Do Precaution,Science, and Innovation Go Together?

In this article we argue that the precautionary principle, as applied to the regulation of science and technology, cannot be considered in any general manner inconsistent with the norms and methods of scientific knowledge generation and justification. Moreover, it does not necessarily curtail scientific‐technological innovation. Our argument flows from a differentiated view of what precaution in regulation means. We first characterize several of the most relevant interpretations given to the precautionary principle in academic debate and regulatory practice. We then use examples of actual precaution‐based regulation to show that, even though science can have varying functions in different circumstances and frames, all of those interpretations recur to scientific method and knowledge, and tend to imply innovation in methods, products, and processes. In fact, the interplay of regulation and innovation in precautionary policy, at least in the case of the interpretations of precaution that our analysis takes into account, could be understood as a way of reconciling the two fundamental science and technology policy functions of promotion and control.     

Emerging Tacts and Selections from Previous Learned Skills: A Comparison between Two Types of Naming

The Analysis of Verbal Behavior - Naming consists of tacting an object and selecting it upon hearing its name as a result of emergence. After acquiring naming, children learn object–name...     

“Shelf-Ready” Print Serials Acquisitions

The focus of this installment of “The Balance Point” is “shelf-ready” print serials acquisitions, including functions associated with traditional consolidation services (ordering, receiving, check-in, labeling, claiming and batch shipments), and the newer capabilities of uploading check-in data automatically into library systems. Featured authors discuss traditional vendor consolidation services, pilot projects and experiments in the pursuit of what they define as genuinely “shelf-ready” periodicals. The authors view obtaining “shelf-ready” print journal issues as an effective and efficient means of managing print serials operations while coping with the demands of managing digital resource acquisitions with limited financial resources.