Common Learning

Consider two agents who learn the value of an unknown parameter by observing a sequence of private signals. The signals are independent and identically distributed across time but not necessarily across agents. We show that when each agent's signal space is finite, the agents will commonly learn the value of the parameter, that is, that the true value of the parameter will become approximate common knowledge. The essential step in this argument is to express the expectation of one agent's signals, conditional on those of the other agent, in terms of a Markov chain. This allows us to invoke a contraction mapping principle ensuring that if one agent's signals are close to those expected under a particular value of the parameter, then that agent expects the other agent's signals to be even closer to those expected under the parameter value. In contrast, if the agents' observations come from a countably infinite signal space, then this contraction mapping property fails. We show by example that common learning can fail in this case.     

Determinants of off-farm work and temporary migration in China

Existing research inadequately explains the factors that drive temporary internal migration in China. Using data for 2005 drawn from 1,903 households in 43 rural villages, we calculate binomial and multinomial logit (BL, MNL) models of probabilities that an adult belongs to one of three categories of worker—on-farm, off-farm, or temporary migrant—as a function of individual and household characteristics. We control for village fixed effects, paying close attention to male/female differences. Nearly all coefficients—even for village dummies—vary significantly by sex. For two variables—age and schooling—the relationships are non-linear. There is an optimal age and amount of schooling that maximizes the probability that a worker will be employed away from the family farm. For schooling, this is low, suggesting that educated workers are underemployed. This might indicate that schooling beyond primary grades is poor quality, or at least inappropriate for the job market.     

Poisson approximation and dna sequence matching

The Poisson distribution is commonly used to model the number of occurrences of independent rare events. However, many instances arise where dependence exists, for example, in counting the length of long head runs in coin tossing, or matches between two DNA sequences. The Chen-Stein method of Poisson approximation yields bounds on the error incurred when approximating the number of occurrences of possibly dependent events by a Poisson random variable of the same mean. In addition to the problems related to the motivating examples from molecular biology involving runs and matches, the method may be applied to questions as varied as calculating probabilities involving extremes of sequences of random variables and approximating the probability of general birthday coincidences.     

Decision‐Making Fairness and Consensus Building in Multisector Community Health Alliances: A Mixed‐Methods Analysis

Given their inherently diverse composition and potentially competing interests, a foundational activity of community health alliances is establishing consensus on the vision and strategies for achieving its goals. Using an organizational justice framework, we examined whether member perceptions of fairness in alliances' decision‐making processes are associated with the perceived level of consensus among members regarding the alliance vision and strategies. We used a mixed‐methods design to examine the relationship between perceptions of fairness and consensus within fourteen multisector community health alliances. Quantitative analysis found the perceived level of consensus to be positively associated with decision‐making transparency (procedural fairness), inclusiveness (procedural fairness), and benefits relative to costs (distributive fairness). Qualitative analysis indicated that the consensus‐building process is facilitated by using formal decision‐making frameworks and engaging alliance members in decision‐making processes early. Alliance leaders may be more successful at building consensus when they recognize the need to appeal to a member's sense of procedural and distributive fairness, and, perhaps equally important, recognize when one rather than the other is called for and draw upon decision‐making processes that most clearly evoke that sense of fairness. Our findings reinforce the importance of fairness in building and sustaining capacity for improving community health.     

Father's involvement in the lives of children in foster care

Limited understandings exist about non‐resident fathers' views of their involvement with their children in foster care placements. Guided by the ecological systems framework, the purpose of this exploratory study was to gain insights into fathers' perceptions of their involvement with a child in foster care. Data were collected from demographic questionnaires and two focus groups with 17 men. Fathers expressed how kinship compared with non‐kinship placements affected their involvement. Fathers were also in agreement that their financial hardships were a significant factor affecting their involvement. Several fathers also reported how they experienced discrimination in the child welfare system as men. Surprisingly, uncommon to findings from other studies, few men viewed the child's mother as being a barrier to their involvement. The findings provide insights into factors requiring attention to help non‐residential fathers become involved with their children.     

Homelessness, Mental Illness and Citizenship

Assertive mental health outreach to homeless persons, which operates under the premise that mental illness must be understood and treated within the individual's social and economic environment, points towards the goals of community membership and 'citizenship'—a connection to the rights, responsibilities, roles, and resources that society offers through public and social institutions and informal 'associational life'—for homeless persons. We argue that the concept of citizenship is a useful framework for approaching these goals. We review the principles of assertive mental health outreach and relevant aspects of contemporary citizenship theory; present a case example of outreach leading to a 'citizenship project'; and discuss the potential benefits and pitfalls of a citizenship framework, including strategies and recommendations for program administrators, researchers and policy makers.