Symbolic Exact Inference for Discrete Probabilistic Programs

The computational burden of probabilistic inference remains a hurdle for applying probabilistic programming languages to practical problems of interest. In this work, we provide a semantic and algorithmic foundation for efficient exact inference on discrete-valued finite-domain imperative probabilistic programs. We leverage and generalize efficient inference procedures for Bayesian networks, which exploit the structure of the network to decompose the inference task, thereby avoiding full path enumeration. To do this, we first compile probabilistic programs to a symbolic representation. Then we adapt techniques from the probabilistic logic programming and artificial intelligence communities in order to perform inference on the symbolic representation. We formalize our approach, prove it sound, and experimentally validate it against existing exact and approximate inference techniques. We show that our inference approach is competitive with inference procedures specialized for Bayesian networks, thereby expanding the class of probabilistic programs that can be practically analyzed

Innovations that Address Socioeconomic, Cultural, and Geographic Barriers to Preventive Oral Health Care

This report focuses on nine oral health innovations that integrate service delivery and workforce models in order to reduce or eliminate socioeconomic, geographic, and cultural barriers to care. Two additional reports in this series describe the remaining programs that provide care in non-dental settings and care to young children. Although the programs are diverse in their approaches as well as in the specific characteristics of the communities they serve, a common factor among them is the implementation of multiple strategies to increase the number of children from low-income families who access preventive care, and also to engage families and communities in investing in and prioritizing oral health. For low-income children and their families, the barriers that must be addressed to increase access to preventive oral health care are numerous. For example, even children covered by public insurance programs face a shortage of dentists that accept Medicaid and who specialize in pediatric dentistry.(Guay, 2004).The effects of poverty intersect with other barriers such as living in remote geographic areas and community-wide history of poor access to dental care in populations such as recent immigrants . Overcoming these barriers requires creative strategies that address transportation barriers; establish welcoming environments for oral health care; and are linguistically and culturally relevant. Each of these nine programs is based on such strategies, including:-Expanding the dental workforce through training new types of providers or adding new providers to their workforce to increase reach and community presence;-Implementing new strategies to increase the cost-effectiveness of care so that more oral health care services are available and accessible;-Providing training and technical assistance that increase opportunities for and competence in delivering oral health education and care to children;-Developing creative service delivery models that address transportation and cultural barriers as well as the fear and stigma associated with dental care that may arise in communities with historically poor access.The findings from the EAs of these programs are synthesized to highlight diverse and innovative strategies for overcoming barriers to access that have potential for rigorous evaluation that could emerge as best practices. If proven effective, these innovative program elements could then be disseminated and replicated to increase access for populations in need of preventive oral health care

Making an Impact: Formalizing Outcome-Driven Grantmaking: Lessons From the Hewlett Population Program

Offers lessons learned and recommendations from Hewlett's experience developing a measurable outcome and scope, researching the field, creating a logic model, metrics, and targets; and comparing the expected social return of potential investments

A Relational Logic for Higher-Order Programs

Relational program verification is a variant of program verification where one can reason about two programs and as a special case about two executions of a single program on different inputs. Relational program verification can be used for reasoning about a broad range of properties, including equivalence and refinement, and specialized notions such as continuity, information flow security or relative cost. In a higher-order setting, relational program verification can be achieved using relational refinement type systems, a form of refinement types where assertions have a relational interpretation. Relational refinement type systems excel at relating structurally equivalent terms but provide limited support for relating terms with very different structures. We present a logic, called Relational Higher Order Logic (RHOL), for proving relational properties of a simply typed $\lambda$-calculus with inductive types and recursive definitions. RHOL retains the type-directed flavour of relational refinement type systems but achieves greater expressivity through rules which simultaneously reason about the two terms as well as rules which only contemplate one of the two terms. We show that RHOL has strong foundations, by proving an equivalence with higher-order logic (HOL), and leverage this equivalence to derive key meta-theoretical properties: subject reduction, admissibility of a transitivity rule and set-theoretical soundness. Moreover, we define sound embeddings for several existing relational type systems such as relational refinement types and type systems for dependency analysis and relative cost, and we verify examples that were out of reach of prior work.Comment: Submitted to ICFP 201

Dental Professionals in Non-Dental Settings

This report focuses on nine oral health innovations seeking to increase access to preventive oral health care in nondental settings. Two additional reports in this series describe the remaining programs that provide care in dental settings and care to young children. The nine innovations described here integrate service delivery and workforce models in order to reduce or eliminate socioeconomic, geographic, and cultural barriers to care. Although the programs are diverse in their approaches as well as in the specific characteristics of the communities they serve, a common factor among them is the implementation of multiple strategies to increase the number of children from low-income families who access preventive care, and also to engage families and communities in investing in and prioritizing oral health. For low-income children and their families, the barriers that must be addressed to increase access to preventive oral health care are numerous. For example, even children covered by public insurance programs face a shortage of dentists that accept Medicaid and who specialize in pediatric dentistry. The effects of poverty intersect with other barriers such as living in remote geographic areas and having a community-wide history of poor access to dental care in populations such as recent immigrants. Overcoming these barriers requires creative strategies that address transportation barriers, establish welcoming environments for oral health care, and are linguistically and culturally relevant. Each of these nine programs is based on such strategies, including:-Expanding the dental workforce through training new types of providers or adding new providers to the workforce toincrease reach and community presence;-Implementing new strategies to increase the cost-effectiveness of care so that more oral health care services are available and accessible;-Providing training and technical assistance that increase opportunities for and competence in delivering oral health education and care to children;-Offering oral health care services in existing, familiar community venues such as schools, Head Start programs and senior centers;-Developing creative service delivery models that address transportation and cultural barriers as well as the fear and stigma associated with dental care that may arise in communities with historically poor access.The findings from the EAs of these programs are synthesized to highlight diverse and innovative strategies for overcoming barriers to access. These strategies have potential for rigorous evaluation and could emerge as best practices. If proven effective, these innovative program elements could then be disseminated and replicated to increase access for populations in need of preventive oral health care