Summary of the Workshop on Issues in Risk Assessment: Quantitative Methods for Developmental Toxicology

This report summarizes the proceedings of a conference on quantitative methods for assessing the risks of developmental toxicants. The conference was planned by a subcommittee of the National Research Council's Committee on Risk Assessment Methodology ⁴ in conjunction with staff from several federal agencies, including the U.S. Environmental Protection Agency, U.S. Food and Drug Administration, U.S. Consumer Products Safety Commission, and Health and Welfare Canada. Issues discussed at the workshop included computerized techniques for hazard identification, use of human and animal data for defining risks in a clinical setting, relationships between end points in developmental toxicity testing, reference dose calculations for developmental toxicology, analysis of quantitative dose-response data, mechanisms of developmental toxicity, physiologically based pharmacokinetic models, and structure-activity relationships. Although a formal consensus was not sought, many participants favored the evolution of quantitative techniques for developmental toxicology risk assessment, including the replacement of lowest observed adverse effect levels (LOAELs) and no observed adverse effect levels (NOAELs) with the benchmark dose methodology.     

First Nations and community economic development: a case study

A training project in a northern Canadian community providedan opportunity to examine participatory planning approachesand the meaning of work in First Nations communities. Focusgroups conducted three years after the unsuccessful interventionof a community economic development (CED) project suggest thatcomplex factors such as lack of support from community leadersand rate of pay for workers determine whether CED is alwaysappropriate in northern, First Nations contexts.     

What to do with “I Don't Know:” Elicitation in Ethnographic & Survey Interviews

When a researcher enters an interview, she has already construed it as being a standard type of communicative event. This article considers how a researcher's construal of a communicative event as either an ethnographic or survey interview shapes the production of information. Interview standards entail epistemological assumptions that directly inform the type of information sought and produced. I consider this process through a comparison of the elicitation techniques I employed in survey and ethnographic interviews conducted during research in Mexico. I draw on theory in linguistic anthropology on the nature of meaning in language, examining how dialogicality and interaction are essential to understanding the construal of communicative events.     

Uncertain Numbers and Uncertainty in the Selection of Input Distributions—Consequences for a Probabilistic Risk Assessment of Contaminated Land

Risks from exposure to contaminated land are often assessed with the aid of mathematical models. The current probabilistic approach is a considerable improvement on previous deterministic risk assessment practices, in that it attempts to characterize uncertainty and variability. However, some inputs continue to be assigned as precise numbers, while others are characterized as precise probability distributions. Such precision is hard to justify, and we show in this article how rounding errors and distribution assumptions can affect an exposure assessment. The outcome of traditional deterministic point estimates and Monte Carlo simulations were compared to probability bounds analyses. Assigning all scalars as imprecise numbers (intervals prescribed by significant digits) added uncertainty to the deterministic point estimate of about one order of magnitude. Similarly, representing probability distributions as probability boxes added several orders of magnitude to the uncertainty of the probabilistic estimate. This indicates that the size of the uncertainty in such assessments is actually much greater than currently reported. The article suggests that full disclosure of the uncertainty may facilitate decision making in opening up a negotiation window. In the risk analysis process, it is also an ethical obligation to clarify the boundary between the scientific and social domains.     

Semiparametric linear transformation models for current status data

Current status data arise when the death of every subject in a study cannot be determined precisely, but is known only to have occurred before or after a random monitoring time. The authors discuss the analysis of such data under semiparametric linear transformation models for which they propose a general inference procedure based on estimating functions. They determine the properties of the estimates they propose for the regression parameters of the model and illustrate their technique using tumorigenicity data.     

What Do Movements Mean? The Value of Participant-Observation

Participant-observation can teach us much about the everyday meanings of doing social activism. I conceptualize these implicit meanings in relation to work in the sociology of culture, and social movement studies, and give examples from activists' everyday interaction. A participant-observer's forays into implicit meanings illuminate three dimensions of activists' experiences: the ways activists practice democratic citizenship in their groups, the ways they build group ties, and the ways they define the meaning of activism itself. By probing these implicit meanings, we can address questions that concern many social movement scholars. We increase our understanding of how movements grow, accomodate conflict, and build alliances, and we can specify which insights are useful in theories of contemporary or new social movements.     

Retirement patterns in Hong Kong: a censored regression analysis

This paper provides an overview of retirement patterns in Hong Kong on the basis of limited data. A censored regression model is used to infer the retirement age from people‘s current retirement status and their current age. This model is equivalent to a restricted probit model, and the interpretation of parameters is straightforward. The results clearly show a negative income effect on the retirement decision. The retirement age seems to be positively related to lifetime earnings but negatively related to the rate of decline of earnings with age. JEL classification: C24, J14, J26 Received May 6, 1996 / Accepted February 5, 1997     

数字素养与农户收入差距:加剧还是缓解?——基于中西部地区的微观证据

数字经济时代,数字贫困问题对农户收入差距的影响引发新的关注。基于2021年中国农村经济与农村金融数据,采用再中心化响应函数(RIF)回归方法探究数字素养对农户收入差距的影响。研究发现:(1)数字素养显著扩大了农户收入差距,并具备明显的马太效应,高数字素养能够攫取更多数字红利,而低数字素养更容易陷入“数字贫困”状态,无法发挥出数字经济的增收效应。(2)应用数字素养会显著加剧农户收入差距,而通用数字素养对农户收入差距的影响并不显著。这种情况也得以印证,现阶段数字“接入鸿沟”已经得以解决,数字“应用鸿沟”差距逐渐凸显。(3)数字素养能够缩小农户财产性收入差距,但会显著扩大工资性收入差距与非农经营性收入差距。脱贫地区受到数字素养的马太效应更强,农户收入差距明显加剧。研究结论证实了我国农村内部存在明显的数字鸿沟,同时数字贫困问题加剧了农户收入差距。新发展阶段我国数字乡村战略的推进不仅要注重农村低收入群体以及弱势群体数字素养的培育,更要加快构建农村数字经济的包容性发展路径,助力农民农村共同富裕的实现。     

哀伤辅导视角下儿童丧亲主题绘本的疗愈效用——基于对9本绘本的叙事分析

为探究儿童丧亲主题绘本的疗愈效用,以哀伤辅导理论为指导框架对《小伤疤》等9本丧亲主题绘本进行叙事分析。研究发现,丧亲主题绘本多数都构建了完整的哀伤历程,分为5个阶段：“故事开端：叙述过去映射正向情感联结;第一次转折：以委婉言语表达死亡事实;情绪高潮：主人公强烈宣泄负面情绪;第二次转折：寻求超越死亡的生命意义;故事结尾：与过去挥手告别开启新生活。”但仍存在一些不足之处可以优化。例如,绘本创作要直面亲人死亡的生物性事实,建构亲人“永生”的现实意义,结合中国本土文化进行创新。作为家长及教育工作者,要关注丧亲儿童的心理健康,灵活运用绘本对儿童进行死亡教育,帮助丧亲儿童走出哀伤。     

媒介再现父职：“新父亲”形象与父职教育契机——基于网络短视频的内容分析

随着网络短视频在日常生活中的广泛渗透,以“爸爸带娃”为主题的家庭父职生活也逐渐媒介化。以微信视频号、小红书和抖音三大主流网络平台的短视频为研究对象,采用内容分析法,探究媒介再现父职中的“新父亲”形象,以及媒介再现父职隐含的父职教育契机。研究发现：媒介再现父职以“关爱父职”为主导,关爱父职影响积极且效果良好;父亲参与意愿和参与主动性强;父亲参与的互动性较为充分;平等、亲和、睿智的父亲形象突出;引流变现下的“花式带娃”等多样化“新父亲”形象。鉴于网络传播的巨大影响力和实效性,媒介再现父职的促进路径为：推动新父职理念的传播与实践转向;设立常人榜样,实现父职教育的日常渗透;明确本土化父职研究方向,拓展父亲情感参与维度。