Time-varying autoregressive conditional duration model

The main goal of this work is to generalize the autoregressive conditional duration (ACD) model applied to times between trades to the case of time-varying parameters. The use of wavelets allows that parameters vary through time and makes possible the modeling of non-stationary processes without preliminary data transformations. The time-varying ACD model estimation was done by maximum-likelihood with standard exponential distributed errors. The properties of the estimators were assessed via bootstrap. We present a simulation exercise for a non-stationary process and an empirical application to a real series, namely the TELEMAR stock. Diagnostic and goodness of fit analysis suggest that the time-varying ACD model simultaneously modeled the dependence between durations, intra-day seasonality and volatility.     

知识城市标杆中的关键因素

本文探讨了新兴城市和地区身份资本的四个关键因素,它们是资本系统方法的一部分.在这些方法中,综合资本系统(GCS)是衡量城市如何为其以知识为基础的发展而发掘能力的一种工具.本文强调GCS中身份资本的要素,以便综合差异性和透明度两方面来考察四个独特城市区域的城市身份.这些基于环境的身份似乎阐明了边缘知识城市是如何在以知识为基础的国际舞台上构建自己的身份优势的.     

The Dynamics of Age and Sex in the Development of Mother–Infant Vocal Communication Between 3 and 11 Months

We followed the nondistressed vocalization dynamics of 30 mother–infant dyads observed in a naturalistic setting using multiple time points between 3 and 11 months to identify subtle relationships between age, sex and maternal behavior ending by 1 year of age with diverging trajectories of nondistressed vocalization. We observed no mean differences between boys and girls in frequency or duration of nondistressed vocalizations at any one time period. However, while these parameters were essentially static for boys, girls showed a quadratic developmental curve, declining in frequency and duration between 6 and 8 months and climbing above their early starting point by 9–11 months. Mothers of boys showed a linear decrease in the duration of their speech over the 9 months of our study. In contrast, mothers of girls showed quadratic patterns of ultimately increasing vocalization frequency and duration, over the months 3–11 of development. Finally, boys' and girls' vocalization contingent to maternal speech revealed no differences. Mothers of boys, however, did not change significantly over time, while mothers of girls showed an increase in contingent responsiveness from 3–5 months to 9–11 months and from 6–8 months to 9–11 months. A similar pattern was followed for object‐related maternal vocal responses.     

A strange tale

We are going through such challenging times that dealing with reality is sometimes easier through fiction. Therefore, we tell the tale of a faraway land where poor women — mostly black — who make a living as domestic servants are particularly impacted by the COVID‐19 pandemic. Their abject bodies are part of a form of necropolitics that separates those who must live from those who can die. Their bodies do not matter, as they are perceived as mere working tools. And what sounds like a strange tale is the true reality of millions of women during the pandemic, in a land that is not so far away as it seems.     

Dopamine receptor genes predict risk preferences,time preferences,and related economic choices

Outside of economics, researchers have recently identified genetic predictors of “sensation-seeking” that have been linked to risky and impulsive behaviors. We examine the implications of these genetic polymorphisms for economic behavior. Our analysis indicates that the 7-repeat allele of the DRD4 gene that regulates dopamine uptake in the brain predicts risk-taking and time preferences in economic experiments that allow for ambiguity, losses and discounting. These genetic polymorphisms can also be used to directly predict financial choice patterns that are consistent with previous findings in the behavioral genetics literature.     

Looking beneath and in-between the hidden surfaces: a critical review of defining,measuring and contextualizing mental health service disparities in the child welfare system

Efforts to understand and respond to racial and ethnic disparities in referrals to and use of mental health services among children involved in the child welfare system are constrained by the lack of consistency in defining and measuring disparities and the lack of clarity as to what causal mechanisms sustain patterns of disparate treatment. Recent developments in the field of public health offer some insight as to how our understanding of similar disparities in child welfare may be advanced. Despite advancements, there is still an insufficient knowledge base from which to offer an alternative definition of disparities that illuminates conceptual and methodological innovation in child welfare research. Based on a critical review of the literature, more exploratory and etiological research grounded in implementation of advanced metrics and multivariate methods is warranted to generate a clear definition. Recommendations are offered to address conceptual ambiguity.     

An Exploration of Adjustment Needs and Efforts of Persons with Dementia After Relocation to a Residential Care Facility

This study examined the adjustment needs and efforts of individuals with dementia after relocation to a residential care facility. This was a qualitative prospective study that involved in-depth face-to-face interviews with 16 individuals with dementia and their family caregivers at 2 and 6 months post-relocation. In their efforts to recreate a sense of home, individuals with dementia had to meet three major highly interrelated and overlapping categories of needs to settle in, fit in, and find meaning in this transition. The satisfactory fulfillment of these adjustment needs resulted in a sense of comfort, connection, and continuity associated with feeling at home. Participants’ efforts to place themselves in their new living environments created a simultaneous need to integrate relocation into their overall sense of self. The results support earlier research indicating that place making is a critical process in the overall psychosocial adjustment to old age. The findings inform supportive interventions to assist individuals with dementia to reconstruct home in a residential care environment.     

The Theory of Planned Behavior as it predicts potential intention to seek mental health services for depression among college students

ABSTRACT

Background: Between 9.5% and 31.3% of college students suffer from depression (American college health association national college health assessment II: reference group executive summary spring 2013. Amer. Coll. Health Assoc. 2013; Eagan K, Stolzenberg EB, Ramirez JJ, Aragon, MC, Suchard, RS, Hurtado S. The American freshman: national norms fall 2014. Higher Educ. Res. Inst.; 2015). Universities need to understand the factors that relate to care-seeking behavior. Objective: Across 3 studies, to relate attitudes, social norms, and perceived behavioral control to intention to seek mental health services, and to investigate barriers to care-seeking. Participants: University college students (N = 845, 64% female, 26% male, and 10% unspecified). Methods: New measures were created in Studies 1 and 2, and were examined using structural equation modeling in Study 3. Results: Partially consistent with the Theory of Planned Behavior (Ajzen, I, Fishbein, M. Understanding Attitudes and Predicting Social Behavior. Englewood Cliffs, NJ: Prentice-Hall; 1980), a model with an excellent fit revealed that more positive attitudes about care and higher perceived behavioral control directly predicted higher intention to seek mental health services. Conclusions: Educating college students about mental health disorders and treatments, enhancing knowledge about available services, and addressing limited access to long-term care might improve treatment rates for students suffering from depression.     

A Longitudinal Examination of Support,Self‐Esteem,and Mexican‐Origin Adolescent Mothers' Parenting Efficacy

Guided by a risk and resilience framework, this study used a prospective longitudinal, multiple‐reporter design to examine how social support from a mother figure during pregnancy interacted with Mexican‐origin adolescent mothers' self‐esteem to inform their parenting efficacy when their children were 10 months old. Using reports of perceived social support by adolescent mothers (M_age = 16.24, SD = 0.99) and their mother figures (M_age = 40.84, SD = 7.04) in 205 dyads, and controlling for demographic factors (i.e., adolescent age, adolescent nativity, family income, mothers' educational attainment, adolescent – mother coresidence) and adolescents' social support from a significant other, the findings indicated that social support during pregnancy was positively associated with adolescent mothers' future parenting efficacy when adolescent mothers had relatively lower self‐esteem. The findings were consistent for adolescents' and mothers' reports and emphasize the value of social support from a mother figure among adolescent mothers with lower self‐esteem. Implications for interventions are presented.