The behavior of the listener,generic extensions,and the communicative adequacy of verbal behavior

The Analysis of Verbal Behavior - Except for a few words, children first become listeners of a word before becoming speakers of the word. The analysis of listener behavior is therefore of...     

Joint Attention,Self‐Recognition,and Neurocognitive Function in Toddlers

Recent studies have attempted to understand the processes involved in joint attention because of its relevance to both atypical and normal development. Data from a recent study of young children with autism suggests that performance on a delay nonmatch to sample (DNMS) task associated with ventromedial prefrontal functions, but not an A‐not‐B/delayed response task associated with dorsolateral prefrontal cortex, was related to joint attention skills (Dawson et al., 2002). Recent research also suggests that joint attention is associated with dorsalmedial brain systems linked to self‐monitoring (Mundy, 2003). This study investigated the relations among joint attention, DNMS, and self‐recognition performance in a longitudinal study of 39 normally developing toddlers from 14 to 18 months. The results indicated that development on the DNMS and self‐recognition tasks, but not a means end task, predicted joint attention at 18 months. Further analysis showed that the model was only significant for initiating joint attention (IJA). The implications of these results for the neuro‐development of IJA are discussed.     

Seven ways of causing the less developed countries' population problem to disappear—in theory

The ways to minimize the difficulties due to population and its growth to be found in current literature have been grouped under seven heads in a far from exhaustive listing:

1. Apply the perspective of rates rather than absolute numbers.
2. Annul the direct negative effects of population with surprising positive indirect effects.
3. Show that neither land nor physical capital is important for development; only labour and human capital count.
4. Exhibit past record of zero correlation between income increase and population increase.
5. Calculate net externality of population increase, but underestimate the externalities falling on women and especially on later generations.
6. Make models of the economy omitting the environment, i.e. implicitly assume the environment is infinite.
7. When all else fails declare that population growth is not bad in itself, but that all evils are due to bad policies—economic, ecological, or urban. Marx thought population growth damaging only under capitalism; now population growth is said to be made innocuous by capitalism.

     

Managers in the Global Economy: A Multilevel Analysis

We examine individual‐ and country‐level determinants of managerial employment, using data from the 1989 to 2009 waves of the World Values and European Values Surveys (n = 89,336 employed adults in 59 countries). Reflecting the rise of the transnational capitalist class, we find that factors related to globalization and international political institutions are most strongly associated with opportunities to join the managerial class relative to factors related to the business‐cycle or development. Additionally, in a subset of countries with detailed occupational information, we find that global trade has a particularly strong, positive association with the odds of being a corporate manager in a large firm.     

Disruption in Parental Co-habitation and its Effects on Short-Term,Medium-Term,and Long-Term Outcomes of Adolescents

In this paper the relationships between a disruption in parental co-habitation and various categories of adolescent outcomes over multiple time horizons are explored. Using data from the National Longitudinal Study of Adolescent Health (Add Health), we estimated the effects of a change from living with both parents to just one, on academic and employment outcomes, the likelihood to indulge in risky behaviors, mental health outcomes and body mass index measures, from less than 1 year to over 14 years after the change. Propensity score matching methods were used to control for individual characteristics and pre-existing differences in the family environment that may increase the chances of separation, and the results are compared to those obtained using ordinary least squares or probit methods. Results showed evidence of adverse effects of living with one parent in the short term, medium term and long term. Adolescents living with one parent had lower academic achievement in all term lengths, poor mental health in the short to medium term, and were more likely to engage in risky behaviors in the medium to long term.     

Poverty and educational achievement in the US: A less-biased estimate using PISA 2012 data

In the current paper, we employ the most recent Programme for International Student Assessment (PISA) data to calculate a less-biased estimate of poverty on US achievement. The PISA was specifically chosen as it is an assessment removed from a specific curriculum and instead focuses on concepts that students should know in order to participate in a global economy. Using a propensity score matching approach, our findings suggest that US students in poverty have notable educational attainment deficiencies compared to a matched group of students who are not in poverty. In other words, when we select two students who have a great deal in common but for the fact that one comes from a poverty background, the student in poverty is expected to perform nearly 28 points, or about a quarter of a standard deviation lower, on the PISA assessment. In real terms, this puts math achievement for children not in poverty on-par with the Organisation for Economic Co-operation and Development (OECD) average, while children in poverty are well below the OECD average.     

Graphical representation of survival curves in the presence of time-dependent categorical covariates with application to liver transplantation

Graphical representation of survival curves is often used to illustrate associations between exposures and time-to-event outcomes. However, when exposures are time-dependent, calculation of survival probabilities is not straightforward. Our aim was to develop a method to estimate time-dependent survival probabilities and represent them graphically. Cox models with time-dependent indicators to represent state changes were fitted, and survival probabilities were plotted using pre-specified times of state changes. Time-varying hazard ratios for the state change were also explored. The method was applied to data from the Adult-to-Adult Living Donor Liver Transplantation Cohort Study (A2ALL). Survival curves showing a ‘split’ at a pre-specified time t allow for the qualitative comparison of survival probabilities between patients with similar baseline covariates who do and do not experience a state change at time t. Time since state change interactions can be visually represented to reflect changing hazard ratios over time. A2ALL study results showed differences in survival probabilities among those who did not receive a transplant, received a living donor transplant, and received a deceased donor transplant. These graphical representations of survival curves with time-dependent indicators improve upon previous methods and allow for clinically meaningful interpretation.