Explaining the Motherhood Wage Penalty During the Early Occupational Career

Prior research shows that mothers earn lower hourly wages than women without children, and that this maternal wage penalty cannot be fully explained by differences between mothers and other women in work experience and job characteristics. This research examines whether the residual motherhood wage penalty results from differences between mothers and other women in the accumulation of work interruptions and breaks in schooling. Using longitudinal data for 486 women followed from ages 19 to 31 in the Minnesota Youth Development Study, we find that accumulated months not in the labor force and not enrolled in school explain the residual pay gap between mothers and other women.     

A Simplified Indicator of Social Well-Being in the United States: Examining the Ecological Impact of Family Formation within a County Level Framework

In 1995, a study entitled ??Does Marriage Matter??? was published by Linda Waite in the journal of Demography, which was concerned with the direction of such causal relationships. While Waite??s examination of the causal relationships associated with marriage, and most other analyses of this type, is primarily concerned with the individual level effects of marriage on a variety of outcomes, little is understood concerning the ecological effect of community marriage rates on levels of aggregate well-being. This study aims to contribute to this gap through the implementation of a recent conceptualization of social well-being as a multi-dimensional measure incorporating both biological, operationalized as average life expectancy, and social phenomena, operationalized as, community level crime rates (Raphael, Making the links: what do health promotion, crime prevention, and social development have in common? in 2004). It is important to understand such aggregate level effects in the face of the existing literature, which relies heavily on relational associations which could be subject to ecological fallacy. Analytic techniques incorporate Exploratory Spatial Data Analysis and spatial regression techniques, due to the high existence of spatial autocorrelation often evident in census data, as a way of understanding the effect of the aggregate level marriage rate on the constructed social well being indicator.     

The potential for mycorrhizae to improve green roof function

The selection of plant species for use on green roofs has been based primarily on their ability to cope with the harsh climatic conditions of the urban rooftop environment. However, green roof plants must also survive in engineered substrates that often lack organic material and beneficial soil microorganisms such as mycorrhizal fungi. We review the literature on mycorrhizae in the context of green roof ecosystems, identifying aspects of green roof functioning that could be enhanced through the integration of mycorrhizal fungi. Although relatively few studies have addressed the influence of mycorrhizal symbiosis on green roof plants specifically, we include information from a variety of naturally occurring habitats with analogous growing conditions. The available literature suggests that the incorporation of mycorrhizal fungi can improve a number of green roof functional attributes, including plant diversity, drought resilience, leachate quality, nutrient use efficiency and carbon sequestration, all while reducing the need for external nutrient inputs. We present evidence that mycorrhizal fungi are of general benefit to green roof ecosystems, and can be effectively integrated into green roof design. We recommend methods for this integration and propose future research directions.     

Urban politics and the study of urban poverty: Promising developments and future directions

The study of urban poverty is alive and well in sociology. The study of urban politics, by contrast, has stagnated. Though scholars agree that politics shapes the creation and durability of urban poverty, analytical connections between the two subfields are rarely made explicit. In this article, I make the case for a more integrated body of research. I first illustrate how urban poverty scholars implicitly discuss politics, and conversely, how urban politics scholars implicitly discuss poverty. I then highlight recent developments in the literature and propose two paths forward—by no means the only paths forward, but two ways to jumpstart greater conversation across both subfields. For the urban poverty literature, a focus on organizations can help scholars analyze political dynamics more directly. And for the urban politics literature, an emphasis on political mechanisms rather than overarching perspectives can disrupt the current theoretical malaise. These two moves can advance both literatures while drawing them closer together.     

Disconnected Geography: A Spatial Analysis of Disconnected Youth in the United States

Since the Great Recession, US policy and advocacy groups have sought to better understand its effect on a group of especially vulnerable young adults who are not enrolled in school or training programs and not participating in the labor market, so called ‘disconnected youth.’ This article distinguishes between disconnected youth and unemployed youth and examines the spatial clustering of these two groups across counties in the US. The focus is to ascertain whether there are differences in underlying contextual factors among groups of counties that are mutually exclusive and spatially disparate (non-adjacent), comprising two types of spatial clusters – high rates of disconnected youth and high rates of unemployed youth. Using restricted, household-level census data inside the Census Research Data Center (RDC) under special permission by the US Census Bureau, we were able to define these two groups using detailed household questionnaires that are not available to researchers outside the RDC. The geospatial patterns in the two types of clusters suggest that places with high concentrations of disconnected youth are distinctly different in terms of underlying characteristics from places with high concentrations of unemployed youth. These differences include, among other things, arrests for synthetic drug production, enclaves of poor in rural areas, persistent poverty in areas, educational attainment in the populace, children in poverty, persons without health insurance, the social capital index, and elders who receive disability benefits. This article provides some preliminary evidence regarding the social forces underlying the two types of observed geospatial clusters and discusses how they differ.     

Automatically Detected Nonverbal Behavior Predicts Creativity in Collaborating Dyads

In the current study we administered a creative task in which two people collaboratively generated novel strategies to conserve resources. During this task, the nonverbal behavior of 104 participants in 52 pairs was tracked and recorded using the Kinect computer vision algorithm. We created a measure of synchrony by correlating movements between the two dyad members, and showed that synchrony occurred—that is, correlations decreased when we increased delay between the recorded movements of pair members. We also demonstrated a link between nonverbal synchrony and creativity, as operationalized by the number of new, valid ideas produced. Linear correlations demonstrated a significant relationship between synchrony and creativity. Finally, models using synchrony scores as input predicted whether dyads were high or low in creativity with a success rate as high as 86.7 % in the more exclusive subsets. We discuss implications for methodological approaches to measuring nonverbal behavior and synchrony, and suggest practical applications which can leverage the current findings.     

Editorial

VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations -     

The effect of infrequent trading on detecting price jumps

The subject of the present study is to analyze how accurately an elaborated price jump detection methodology by Barndorff-Nielsen and Shephard (J. Financ. Econom. 2:1–37, 2004a; 4:1–30, 2006) applies to financial time series characterized by less frequent trading. In this context, it is of primary interest to understand the impact of infrequent trading on two test statistics, applicable to disentangle contributions from price jumps to realized variance. In a simulation study, evidence is found that infrequent trading induces a sizable distortion of the test statistics towards overrejection. A new empirical investigation using high frequency information of the most heavily traded electricity forward contract of the Nord Pool Energy Exchange corroborates the evidence of the simulation. In line with the theory, a “zero-return-adjusted estimation” is introduced to reduce the bias in the test statistics, both illustrated in the simulation study and empirical case.     

Synthetic data method to incorporate external information into a current study

We consider the situation where there is a known regression model that can be used to predict an outcome, Y, from a set of predictor variables X . A new variable B is expected to enhance the prediction of Y. A dataset of size n containing Y, X and B is available, and the challenge is to build an improved model for Y| X ,B that uses both the available individual level data and some summary information obtained from the known model for Y| X . We propose a synthetic data approach, which consists of creating m additional synthetic data observations, and then analyzing the combined dataset of size n + m to estimate the parameters of the Y| X ,B model. This combined dataset of size n + m now has missing values of B for m of the observations, and is analyzed using methods that can handle missing data (e.g., multiple imputation). We present simulation studies and illustrate the method using data from the Prostate Cancer Prevention Trial. Though the synthetic data method is applicable to a general regression context, to provide some justification, we show in two special cases that the asymptotic variances of the parameter estimates in the Y| X ,B model are identical to those from an alternative constrained maximum likelihood estimation approach. This correspondence in special cases and the method's broad applicability makes it appealing for use across diverse scenarios. The Canadian Journal of Statistics 47: 580–603; 2019 © 2019 Statistical Society of Canada     

Colonial Military Garrisons as Labor-Market Shocks: Quebec City and Boston, 1760–1775

The military occupation of Boston in 1768 shocked the city's labor market. The soldiers, who were expected to supplement their pay by working for local businesses, constituted an influx equal to 12.5 percent of greater Boston's population. To assess the importance of this shock, we use the case of Quebec City, which experienced the reverse process (i.e., a reduction in the British military presence from close to 18 percent of the region's population to less than 1 percent). We argue that, in Boston, the combination of the large influx of soldiers and a heavy tax on the local population in the form of the billeting system caused an important wage reduction, while the lighter billeting system of Quebec City and the winding down of the garrison pushed wages up. We tie these experiences to political developments in the 1770s.