Mobile phones and core network growth in Kenya: Strengthening weak ties

In contrast to recent US studies showing a decrease in core network size, our Kenyan data reveals substantial network growth. We attribute this to the diffusion of mobile telephones. Results from pooled survey data from Nairobi professionals and entrepreneurs in 2002 and 2007 as well as qualitative interviews from 2007 to 2009 show virtual saturation in the diffusion of phones during this period, but no direct effect of technology use. What explains this puzzle is a network effect of mobile telephony: increased technological access to existing networks in a context of resource scarcity leads to a strengthening of weak ties and the enhancement of core networks among Kenyans. Video ethnographic data before and after the 2007 post-election unrest supports this interpretation, showing that mobile phones are a crucial resource in managing interpersonal networks for instrumental purposes.     

A discrete analog of Gumbel distribution: properties,parameter estimation and applications

A discrete version of the Gumbel distribution (Type-I Extreme Value distribution) has been derived by using the general approach of discretization of a continuous distribution. Important distributional and reliability properties have been explored. It has been shown that depending on the choice of parameters the proposed distribution can be positively or negatively skewed; possess long-tail(s). Log-concavity of the distribution and consequent results have been established. Estimation of parameters by method of maximum likelihood, method of moments, and method of proportions has been discussed. A method of checking model adequacy and regression type estimation based on empirical survival function has also been examined. A simulation study has been carried out to compare and check the efficacy of the three methods of estimations. The distribution has been applied to model three real count data sets from diverse application area namely, survival times in number of days, maximum annual floods data from Brazil and goal differences in English premier league, and the results show the relevance of the proposed distribution.     

Organizing for Education: A Cross-National,Longitudinal Study of Civil Society Organizations and Education Outcomes

We address two views from organization theory to consider the expansion and effects of nonprofits in education: first, a functional view emphasizing the direct effect of work of civil society organizations (CSOs) and, second, a phenomenological neoinstitutional view focusing on the cultural meaning of education CSOs as indicators of a rationalized, liberal world society. We use panel regression models with country fixed effects to analyze the cross-national expansion of domestic education CSO sectors in 130 countries from 1970 to 2014. We then examine the association between the size of the domestic education CSO sector and memberships in international non-governmental organizations (INGOs) with education outcomes, including spending, education aid, secondary and tertiary enrollments, and the share of women in secondary and tertiary education. Results show that INGO memberships, an expanded state, and an expanded education system are highly associated with the expansion of a domestic education CSO sector. Both domestic CSOs and INGO memberships tend to have a significant, positive relationship with education outcomes net of other factors. We also find preliminary evidence indicating that the causal forces at play are more complex than a straightforward direct effect of education CSOs doing good work. Specifically, CSOs, at least in part, are indicators of a Western, liberal model of a proper modern society; the underpinning culture, represented by CSOs, accounts for some educational expansion above and beyond the benefit (or harm) caused by any given entity.     

CAN SCHOOL SPORTS REDUCE RACIAL GAPS IN TRUANCY AND ACHIEVEMENT?

While existing research supports that participation in high‐school athletics is associated with better education and labor‐market outcomes, the mechanisms through which these benefits accrue are not well established. Using individual microdata collected daily, and team‐specific schedules, we retrieve estimates of the causal effect of high‐school athletic participation on absenteeism, suggesting that participation decreases absences, driven primarily by reductions in unexcused absences in boys. There are also strong game‐day effects in truancy, in both boys and girls, with truancy declines on game days more than offset by subsequent absenteeism. Important heterogeneity by race, gender, and family structure may serve to substantially reduce racial gaps in truancy and achievement. (JEL I21, L83)     

Do designated drivers and workplace policies effect alcohol consumption?

Is there a link between designated driver usage and alcohol consumption? We hypothesize that the use of a designated driver lowers the cost of drinking which, in turn, increases alcohol consumption. We examine the effect on drinking intensity (which incorporates low levels of alcohol use) and binge drinking (which measures greater alcohol use), using a proxy for designated driver usage. If workplace rules forbid alcohol use for safety or other reasons, a large potential cost of drinking is the possible job loss (or other penalty) incurred if an employed person tests positive for alcohol. We add variables to our model related to workplace policies on alcohol use by workers to ascertain if designated drivers still influence drinking. We test these hypotheses utilizing a large dataset from the 2006 and 2007 National Survey on Drug Use and Health (NSDUH) which includes several measures of alcohol use, in addition to a host of other correlates. Findings reveal that our proxy for designated driver use increases the incidence of drinking and the results hold even after controlling for workplace alcohol testing.     

On the relevance and accountability of dialect: Conversation analysis and dialect contact

The present study seeks to illustrate how the theory and method of conversation analysis (CA) can be used to begin to unpack the notion of ‘contact’ in contact linguistics research. After reviewing language and dialect contact as they are traditionally conceptualized, we describe an additional set of questions inspired by CA's fundamental concern with relevance and accountability. It is argued that, by analyzing the structure and design of turn‐by‐turn talk in situations of dialect contact, we are able to investigate how co‐participants themselves go about carving out the boundaries of their respective dialects, how they can link those dialects to social identities, and how those social identities can become ‘procedurally consequential’ for the design of subsequent talk between the interlocutors. It is ultimately hypothesized that relevance and accountability at the micro‐interactional level may provide new insight into the moment‐by‐moment mechanisms that bring about the comparatively more macro‐level outcomes of dialect contact (e.g. leveling, koineization, etc.) that have been previously identified in contact linguistics research.     

Modeling Pathology Workload and Complexity to Manage Risks and Improve Patient Quality and Safety

Anatomic pathology (AP) laboratories provide critical diagnostic information that help determine patient treatments and outcomes, but the risks of AP operations and their impact on patient safety and quality of care remain poorly recognized and undermanaged. Hospital-based laboratories face an operational and risk management challenge because clinical work of unknown quantity and complexity arrives with little advance notice, which results in fluctuations in workload that can push operations beyond planned capacity, leading to diagnostic delays and potential errors. Modeling the dynamics of workload and complexity in AP offers the opportunity to better use available information to manage risks. We developed a stock-and-flow model of a typical AP laboratory operation and identified key exogenous inputs that drive AP work. To test the model, we generated training and validations data sets by combining data from the electronic medical records and laboratory information systems over multiple years. We demonstrate the implementation of 10-day AP work forecast generated on a daily basis, and show its performance in comparison with actual work. Although the model somewhat underpredicts work as currently implemented, it provides a framework for prospective management of resources to ensure quality during workload surges. Although full implementation requires additional model development, we show that AP workload largely depends on few and accessible clinical inputs. Recognizing that level loading of work in a hospital is not practical, predictive modeling of work can empower laboratories to triage, schedule, or mobilize resources more effectively and better manage risks that reduce the quality or timeliness of diagnostic information.     

Military service and marital dissolution: a trajectory analysis

Military service adds additional challenges for married couples. Previous literature on service and marital stability is comprised of mixed results and has often ignored the timing of these effects. This timing is important as it helps disclose the nature of causality and has implications for both military and social security policies. Using a trajectory specification, I estimate the effect of military service on the likelihood of divorce during the volunteer’s period of service and the years following. Two veteran cohorts are examined, those who served during the early twenty-first century wars and those who served during the early 1980s. Among my results, the former cohort is shown to have had their divorce probability increased in the first 2 years post-service, while the opposite effect is found for the latter cohort. Unlike many previous studies of military service and marital stability, I find that effects are not overly dissimilar across racial groups.