Child witness support and preparation: are parents/caregivers ignored?

Over recent decades research has confirmed the sensible belief that to participate in criminal proceedings (that were designed for adults) child witnesses may benefit from support and preparation. This is so even in countries where special measures have been introduced to make it less arduous for children to give their testimony (e.g. closed circuit television to allow children to testify away from the actual courtroom; video recorded evidence‐in‐chief). Indeed, it could be argued that as more and more children provide testimony (e.g. as alleged victims or witnesses), the more comprehensive should be preparation and support programmes for them. However, while in some countries preparation and support programmes are now offered to such children, the needs of these children's (non‐offending) parents/caregivers seem to be ignored. This paper contends not only that these adults need preparation and support but also that the provision of this is likely to benefit child witnesses. Copyright © 2006 John Wiley & Sons, Ltd.     

Physiologically-Based Pharmacokinetic Model for Trichloroethylene Considering Enterohepatic Recirculation of Major Metabolites

Trichloroacetic acid (TCA) is major metabolite of trichloroethylene (TRI) thought to contribute to its hepatocarcinogenic effects in mice. Recent studies have shown that peak blood concentrations of TCA in rats do not occur until approximately 12 hours following an oral dose of TRI. However, blood concentrations of TRI reach maximum within an hour and are nondetectable after 2 hours.⁽¹⁾ The results of study which examined the enterohepatic recirculation (EHC) of the principle TRI metabolited⁽²⁾ was used to develop physiologically-based pharmacokinetic model for TRI, which includes enterohepatic recirculation of its metabolites. The model quantitatively predicts the uptake, distribution and elimination of TRI, trichloroethanol, trichloroethanol-glucuronide, and TCA and includes production of metabolites through the enterohepatic recirculation pathway. Physiologic parameters used in the model were obtained from the literature.^(3.4) Parameters for TRI metabolism were taken from Fisher et al.⁽⁵⁾ Other kinetic parameters were found in the literature or estimated from experimental data.⁽²⁾ The model was calibrated to data from experiments of an earlier study where TRI was orally administered⁽²⁾ Verification of the model was conducted using data on the enterohepatic recirculation of TCEOH and TCA⁽²⁾ chloral hydrate data (infusion doses) from Merdink,⁽¹⁾ and TRI data from Templin(l) and Larson and Bull.⁽¹⁾     

Efficiency of reduced logistic regression models

One feature of the usual polychotomous logistic regression model for categorical outcomes is that a covariate must be included in all the regression equations. If a covariate is not important in all of them, the procedure will estimate unnecessary parameters. More flexible approaches allow different subsets of covariates in different regressions. One alternative uses individualized regressions which express the polychotomous model as a series of dichotomous models. Another uses a model in which a reduced set of parameters is simultaneously estimated for all the regressions. Large-sample efficiencies of these procedures were compared in a variety of circumstances in which there was a common baseline category for the outcome and the covariates were normally distributed. For a correctly specified model, the reduced estimates were over 100% efficient for nonzero slope parameters and up to 500% efficient when the baseline frequency and the effect of interest were small. The individualized estimates could have efficiencies less than 50% when the effect of interest was large, but were also up to 130% efficient when the baseline frequency was large and the effect of interest was small. Efficiency was usually enhanced by correlation among the covariates. For an underspecified reduced model, asymptotic bias in the reduced estimates was approximately proportional to the magnitude of the omitted parameter and to the reciprocal of the baseline frequency.     

Detecting Deceit via Analysis of Verbal and Nonverbal Behavior

We examined the hypotheses that (1) a systematic analysis of nonverbal behavior could be useful in the detection of deceit and (2) that lie detection would be most accurate if both verbal and nonverbal indicators of deception are taken into account. Seventy-three nursing students participated in a study about telling lies and either told the truth or lied about a film they had just seen. The interviews were videotaped and audiotaped, and the nonverbal behavior (NVB) and speech content of the liars and truth tellers were analyzed, the latter with the Criteria-Based Content Analysis technique (CBCA) and the Reality Monitoring technique (RM). Results revealed several nonverbal and verbal indicators of deception. On the basis of nonverbal behavior alone, 78% of the lies and truths could be correctly classified. An even higher percentage could be correctly classified when all three detection techniques (i.e., NVB, CBCA, RM) were taken into account.     

A characterization of the efficiency of individualized logistic regressions

The use of individualized regressions, which reduces the polychotomous logistic regression model to several dichotomous models, has been proposed as a solution to some practical difficulties for binary covariates (Begg and Gray 1984, Biometrika, 71, 11–18). Its disadvantages, however, include loss of efficiency and the complexity of making comparisons among regressions. Using expressions for the large-sample distribution of the maximum-likelihood estimates, the efficiency of the individualized procedure relative to the polychotomous procedure is evaluated for the case in which the covariates are assumed to follow a multivariate normal distribution. The relative efficiency when the logistic slope vectors from different regressions are collinear can be substantially lower compared to the efficiency with orthogonal slope vectors. Further evaluations for binary covariates using collinear and orthogonal slope parametrizations lead to a similar characterization.     

The Wage Gap between Foreign and Spanish Nationals in Spain: an Analysis Using Matched Employer–Employee Data

In this paper, we analyse wage differences between foreign and Spanish nationals in Spain. This analysis is relevant because Spain has witnessed a sharp increase in the proportion of foreign workers over the past decade. In our analysis, we explicitly account for unobserved heterogeneity at firm level, a situation which occurs when relevant covariates (for example, those connected to a specific firm's production process) are not included in the model because they are unmeasurable, unobservable or unavailable for the researcher. When accounting for such heterogeneity, our results show that wage gaps between foreign nationals from developing countries and Spanish nationals range between ?6.35 per cent and ?11.30 per cent. We also find that wage differences, between Spanish nationals and others in the same firm and job, are substantially greater for almost every group of low‐tenured foreign workers and also for those holding open‐ended contracts.