Influences of Infant‐Directed Speech on Early Word Recognition

When addressing infants, many adults adopt a particular type of speech, known as infant‐directed speech (IDS). IDS is characterized by exaggerated intonation, as well as reduced speech rate, shorter utterance duration, and grammatical simplification. It is commonly asserted that IDS serves in part to facilitate language learning. Although intuitively appealing, direct empirical tests of this claim are surprisingly scarce. Additionally, studies that have examined associations between IDS and language learning have measured learning within a single laboratory session rather than the type of long‐term storage of information necessary for word learning. In this study, 7‐ and 8‐month‐old infants' long‐term memory for words was assessed when words were spoken in IDS and adult‐directed speech (ADS). Word recognition over the long term was successful for words introduced in IDS, but not for those introduced in ADS, regardless of the register in which recognition stimuli were produced. Findings are discussed in the context of the influence of particular input styles on emergent word knowledge in prelexical infants.     

ANOVA models for Brownian motion

We investigate longitudinal models having Brownian-motion covariance structure. We show that any such model can be viewed as arising from a related “timeless” classical linear model where sample sizes correspond to longitudinal observation times. This relationship is of practical impact when there are closed-form ANOVA tables for the related classical model. Such tables can be directly transformed into the analogous tables for the original longitudinal model. We in particular provide complete results for one-way fixed and random effects ANOVA on the drift parameter in Brownian motion, and illustrate its use in estimating heterogeneity in tumor growth rates.     

Indian agricultural policy: An applied general equilibrium model

A ten-sector, sequential applied general equilibrium model is formulated, estimated, and stimulated for analyzing agricultural policy choices for India until year 2000. Ten groups of consumers (five of them rural), each with its own preferences and claims on output are recognized in the model, the groups distinguished by the range of their per capita household (real) consumption expenditure. The simulations compare: four policies with respect to the compulsory purchase and subsidized distribution to consumers of a limited amount of foodgrains and four foreign trade and aid scenarios. Procuring and freely distributing 100 kgs of grain per capita per year and financing the cost through additional taxation improves income distribution with no reduction in growth. On the other hand, the same distributional policy financed by reducing investment has a negative impact on growth.     

The Effectiveness of Decisional Guidance: An Empirical Evaluation

Decisional guidance is defined as how a decision support system (DSS) influences its users as they structure and execute the decision‐making process. It is assumed that decisional guidance has profound effects on decision making, but these effects are understudied and empirically unproven. This paper describes an empirical, laboratory‐experiment‐based evaluation of the effectiveness of deliberate decisional guidance and its four types. We developed and used a comprehensive model consisting of four evaluation criteria: decision quality, user satisfaction, user learning, and decision‐making efficiency. On these criteria, we compared decisional guidance versus no guidance, informative versus suggestive decisional guidance, and predefined versus dynamic decisional guidance. We found that deliberate decisional guidance was more effective on all four criteria; suggestive guidance was more effective in improving decision quality and user satisfaction, and informative guidance was more effective in user learning about the problem domain, whereas dynamic guidance was more effective than predefined guidance in improving decision quality and user learning; and both suggestive guidance and dynamic guidance reduced the decision time.     

An econometric model of the agricultural sector of the Indian economy

The interrelationships between production, consumption, and stocks are studied in an interdependent framework for two groups of agricultural commodities, namely foodgrains and nonfoodgrains, with a view to obtain policy guidelines for agricultural growth. The model is formulated with aggregate information over the period 1951–1975 and both static and dynamic simulation along with multiplier analysis are carried out to assess the performance of the model. The study reveals that if there had been no PL 480 aid from the U.S. imports, foodgrain prices would have been higher than observed prices. Ex-ante forecasts to 1985 suggest some need for adequate planning with regard to stockbuilding.     

Racial and Ethnic Diversity in Senior Centers: Comparing Participant Characteristics in More and Less Multicultural Settings

The 2008 Health Indicators Project surveyed a probability sample (N = 1,870) of New York City senior center participants. Attendees of racially and ethnically diverse and nondiverse senior centers were compared across 5 domains: demographics; health and quality of life; social support networks; neighborhood perceptions and engagement; health service access/utilization. Although homogeneous and diverse center participants demonstrate similar health and quality-of-life outcomes, those from diverse centers demonstrate greater risk of social isolation, receive less family support, and more likely seek medical care from hospitals or community clinics. Implications and future directions for research, practice and policy are discussed.     

Family Well-Being During the COVID-19 Pandemic: The Risks of Financial Insecurity and Coping

During the COVID-19 pandemic, families have experienced unprecedented financial and social disruptions. We studied the impact of preexisting psychosocial factors and pandemic-related financial and social disruptions in relation to family well-being among N = 4091 adolescents and parents during early summer 2020, participating in the Adolescent Brain Cognitive Development^SM Study. Poorer family well-being was linked to prepandemic psychosocial and financial adversity and was associated with pandemic-related material hardship and social disruptions to routines. Parental alcohol use increased risk for worsening of family relationships, while a greater endorsement of coping strategies was mainly associated with overall better family well-being. Financial and mental health support may be critical for family well-being during and after a widespread crisis, such as the COVID-19 pandemic.     

Labour mobility and regional disparities: the role of female labour participation

Unemployment rates, as well as income per capita, differ vastly across the regions of Europe. Labour mobility can play a role in resolving regional disparities. This paper focuses on the questions of why labour mobility is low in the EU and how it is possible that it remains low. We explore whether changes in male and female labour participation act as an important alternative adjustment mechanism. We answer this question in the affirmative. We argue that female labour participation is very important in adjusting to regional disparities.

Penalized variable selection in competing risks regression

Penalized variable selection methods have been extensively studied for standard time-to-event data. Such methods cannot be directly applied when subjects are at risk of multiple mutually exclusive events, known as competing risks. The proportional subdistribution hazard (PSH) model proposed by Fine and Gray (J Am Stat Assoc 94:496–509, 1999) has become a popular semi-parametric model for time-to-event data with competing risks. It allows for direct assessment of covariate effects on the cumulative incidence function. In this paper, we propose a general penalized variable selection strategy that simultaneously handles variable selection and parameter estimation in the PSH model. We rigorously establish the asymptotic properties of the proposed penalized estimators and modify the coordinate descent algorithm for implementation. Simulation studies are conducted to demonstrate the good performance of the proposed method. Data from deceased donor kidney transplants from the United Network of Organ Sharing illustrate the utility of the proposed method.