Changes in Cohabitation After the Birth of the First Child in Chile

In Chile, as in other Latin American countries, most children born outside of marriage are born to currently cohabiting couples. After having their first child, parents could marry, separate, or experience no change in union status. This paper explores changes in cohabitation that occur after the birth of the first child in Chile and analyzes how these changes might be associated with the birth of children and socioeconomic status. The data come from the New Chilean Family Survey, a small longitudinal survey administered to women after giving birth (n = 564). I use life tables and event history techniques to assess changes in respondent union status up to 4 years after the birth of the first child, and to study the transitions out of cohabitation. The results indicate that the unions in the sample are relatively stable, because less than 40 percent of cohabiters change status over the period of 4 years. However, marriage still appears to be a more stable type of union than cohabitation. Among cohabiters, there is evidence of a nonlinear relation between union stability and educational attainment, because the most stable unions are the unions of women with a high school diploma and not the unions of women who did not complete their secondary education. Having planned the first birth and the birth of an additional child seems to consolidate the cohabiting union, because these variables are not related to the entry into marriage, but they are related to lower risks of dissolution. These findings suggest that the Chilean case differs from the cases of Europe and the United States.     

Computing unique maximum matchings in $$$$ time for König–Egerváry graphs and unicyclic graphs

Let \(\alpha \left( G\right) \) denote the maximum size of an independent set of vertices and \(\mu \left( G\right) \) be the cardinality of a maximum matching in a graph \(G\). A matching saturating all the vertices is a perfect matching. If \(\alpha \left( G\right) +\mu \left( G\right) =\left| V(G)\right| \), then \(G\) is called a König–Egerváry graph. A graph is unicyclic if it is connected and has a unique cycle. It is known that a maximum matching can be found in \(O(m\cdot \sqrt{n})\) time for a graph with \(n\) vertices and \(m\) edges. Bartha (Proceedings of the 8th joint conference on mathematics and computer science, Komárno, Slovakia, 2010) conjectured that a unique perfect matching, if it exists, can be found in \(O(m)\) time. In this paper we validate this conjecture for König–Egerváry graphs and unicylic graphs. We propose a variation of Karp–Sipser leaf-removal algorithm (Karp and Sipser in Proceedings of the 22nd annual IEEE symposium on foundations of computer science, 364–375, 1981) , which ends with an empty graph if and only if the original graph is a König–Egerváry graph with a unique perfect matching (obtained as an output as well). We also show that a unicyclic non-bipartite graph \(G\) may have at most one perfect matching, and this is the case where \(G\) is a König–Egerváry graph.     

A Manager is a Manager is a Manager? Race and Managerial Impact on Organizational Performance

Contemporary scientific analyses of public organizations underscore the salience of management for understanding how governmental bureaucracies perform. Yet little is known of administrators from minority social groups, and whether their organizations perform better or worse than other bureaucracies. Emphasizing the impact of network engagement on organizational performance, this exploratory study addresses this important research deficiency. A critical component of the analysis presented is the differential impact of administrative engagement with internal and external networks on minority and status quo clientele outcomes. The findings have important implications for studies of managerial networking, equity, and representation in public organizations.     

Did Australia’s Baby Bonus Increase Fertility Intentions and Births?

In May 2004, the Australian government announced a “Baby Bonus” policy, paying women an initial A$3,000 per new child. We use household panel data from the Household, Income and Labour Dynamics in Australia Survey (N = 14,932) and a simultaneous equations approach to analyze the effects of this bonus on fertility intentions and ultimately births. The results indicate that opportunity costs influence intentions and births in predictable ways. Fertility intentions rose after the announcement of the Baby Bonus, and the birth rate is estimated to have risen modestly as a result. The marginal cost to the government for an additional birth is estimated to be at least A$3,000 per new child. We use household panel data from the Household, Income and Labour Dynamics in Australia Survey (N = 14,932) and a simultaneous equations approach to analyze the effects of this bonus on fertility intentions and ultimately births. The results indicate that opportunity costs influence intentions and births in predictable ways. Fertility intentions rose after the announcement of the Baby Bonus, and the birth rate is estimated to have risen modestly as a result. The marginal cost to the government for an additional birth is estimated to be at least A126,000.     

A Demographic Profile of Obesity in the Adult and Veteran US Populations in 2008

Obesity is increasing in the US population and seems to be disproportionately burdening disadvantaged groups. Veterans using the Veterans Healthcare System (VHS) tend to be more disadvantaged socioeconomically than the general population and in poorer health. It is important to understand how the veteran population differs from or is similar to the general population and whether the VHS is able to mediate obesity risk among veterans. This research assesses the sociodemographic, behavioral, and health risk factors for obesity in the US adult and veteran populations in 2008. We use data from the 2008 Behavioral Risk Factor Surveillance System (BRFSS) to empirically assess predictors of obesity risk. We find that women have lower odds of obesity than men once controls for sociodemographic, behavioral, and health conditions are included in our models. We also observe a veteran obesity disadvantage in the full adult sample when conducting bivariate tests, but no significant association with the odds of obesity in the logistic regression models among veterans and non-veterans. Gender specific models indicate that male veterans have increased odds of obesity compared to non-veterans, but no difference in obesity risks among veterans and non-veterans are noted for women, controlling for all variables. Further, we find no significant differences in the odds of obesity of veterans using VHS for all, some, or none of their health care needs; further no significant gender differences in obesity risk were observed among VHS usages and non-users. Based on the strong, positive association between the number of chronic health conditions and the odds of obesity, we suggest that health policy should focus efforts on weight management counseling for obese patients that have obesity related co-morbidities, and more targeted attention to male veterans would help to address the high level of obesity in this vulnerable population group.     

Der Laie im Fokus nuklearer Debatten

Since the early 1960s, the French nuclear industry is marked by a structural dichotomy between experts and the general public. Even though citizens secured themselves a place in the decision making process, their scope of action is limited and linked to a discursively framed lay identity. The study focuses on the operationalisation of the lay terminology by the actors of the French nuclear debate. We focus our analysis on two groups of actors: 1) governmental and pro-nuclear organisations and 2) nongovernmental and anti-nuclear organisations. Our aim is to analyze the real-time implications of a discursive regime of participation on the public engagement in science.     

Do downward private transfers enhance maternal labor supply? Evidence from around Europe

Using data on 2,317 mother–daughter pairs from 10 European countries, we investigate the impact of downward time and monetary transfers on the career choices of transfer-receiving young mothers. For Europe as a whole, we find a strong positive effect of grandchild care on the labor force participation and the degree of labor market involvement of the young mother, but no impact of monetary transfers on either of these decisions. Both recipients and donors with better endowments are more likely to participate in a monetary transaction, while mothers with lower level of human capital are more likely to provide time transfers to their better endowed daughters.     

Decision-Making and Evidence in Direct Practice

This article presents the results of research designed to explore decision-making by direct practitioners in selected non-profit human service settings. Forty interviews were conducted with workers at front-line, supervisory and higher-management levels. The research questions included; what sources of information are used in decision-making, what variables enhance or impede utilization of evidence-based knowledge in decision-making and what would be important resources for improving availability, access and utilization of evidence-based knowledge in decision-making? Our results indicate that respondents relied most heavily on experience; on their professional values and beliefs, and on an empathic understanding of their clients’ uniqueness. Compared to these sources of information use of research and the professional literature were less enthusiastically endorsed.     

Implementing integrated pest management in professional lawn care: a case study

Human choices regarding land cover management practices may influence ecosystem services provided by urban green spaces. We conducted a 2-year study to compare biological (weed, insect, and disease), aesthetic (lawn quality), and economic (lawn care program cost) attributes of an integrated pest management (IPM) program, in which pesticides are applied on the basis of treatment thresholds, with a standard program, in which pesticides are applied on a calendar basis without pest monitoring. Both programs were managed by a professional lawn care operator. Although weed incidence was low, the IPM program had significantly more lawns with weed presence than the standard program during 2005 and 2006. However, only 21% of the IPM lawns required herbicide applications in 2005, and none exceeded the treatment threshold (5% weed cover) in 2006 as compared to 100% of the standard program lawns being treated for weeds in both years. The IPM program also had significantly more lawns with insect damage than the standard program during June 2005 and August 2005, but not September 2005 and throughout 2006. Only 28% of the IPM lawns required insecticide applications in 2005 and none exceeded the threshold (5% insect damage) in 2006 whereas all of the lawns in the standard program received insecticide treatments in both years. Rhizoctonia blight was present on some of the lawns, but was not a common problem. Although lawn quality was high for both programs (>8, on a scale of 1–9), it was significantly higher for standard than for IPM program lawns during 2005, and June 2006 and September 2006, but not August 2006. The annual lawn management costs were lower for the IPM (281.50) than the standard program (281.50) than the standard program (458.06). Thirty one percent of the IPM program customers who continued with the study in 2006 did so because they were satisfied with the IPM program. Among those who did not continue with the program, 33% cited weed or insect problems, while 33% expected better results. The implications of these findings for implementation of IPM in professional lawn care are further discussed.     

Bayesian local influence for survival models

The aim of this paper is to develop a Bayesian local influence method (Zhu et al. 2009, submitted) for assessing minor perturbations to the prior, the sampling distribution, and individual observations in survival analysis. We introduce a perturbation model to characterize simultaneous (or individual) perturbations to the data, the prior distribution, and the sampling distribution. We construct a Bayesian perturbation manifold to the perturbation model and calculate its associated geometric quantities including the metric tensor to characterize the intrinsic structure of the perturbation model (or perturbation scheme). We develop local influence measures based on several objective functions to quantify the degree of various perturbations to statistical models. We carry out several simulation studies and analyze two real data sets to illustrate our Bayesian local influence method in detecting influential observations, and for characterizing the sensitivity to the prior distribution and hazard function.