Estimating the accuracy of geographical imputation

<p>Abstract</p> <p>Background</p> <p>To reduce the number of non-geocoded cases researchers and organizations sometimes include cases geocoded to postal code centroids along with cases geocoded with the greater precision of a full street address. Some analysts then use the postal code to assign information to the cases from finer-level geographies such as a census tract. Assignment is commonly completed using either a postal centroid or by a geographical imputation method which assigns a location by using both the demographic characteristics of the case and the population characteristics of the postal delivery area. To date no systematic evaluation of geographical imputation methods ("geo-imputation") has been completed. The objective of this study was to determine the accuracy of census tract assignment using geo-imputation.</p> <p>Methods</p> <p>Using a large dataset of breast, prostate and colorectal cancer cases reported to the New Jersey Cancer Registry, we determined how often cases were assigned to the correct census tract using alternate strategies of demographic based geo-imputation, and using assignments obtained from postal code centroids. Assignment accuracy was measured by comparing the tract assigned with the tract originally identified from the full street address.</p> <p>Results</p> <p>Assigning cases to census tracts using the race/ethnicity population distribution within a postal code resulted in more correctly assigned cases than when using postal code centroids. The addition of age characteristics increased the match rates even further. Match rates were highly dependent on both the geographic distribution of race/ethnicity groups and population density.</p> <p>Conclusion</p> <p>Geo-imputation appears to offer some advantages and no serious drawbacks as compared with the alternative of assigning cases to census tracts based on postal code centroids. For a specific analysis, researchers will still need to consider the potential impact of geocoding quality on their results and evaluate the possibility that it might introduce geographical bias.</p

Oxford nanopore sequencing enables rapid discovery of single-domain antibodies from phage display libraries.

Antibody (Ab) repertoire sequencing using high-throughput massively parallel technologies has contributed substantially to the understanding of Ab responses following infection, vaccination and autoimmunity. Because individual B-cell receptors are recombined and diversified somatically, genomic comparisons are limited, and distinguishing rare variants from sequencing errors is a major challenge. Oxford Nanopore Technologies' MinION is a highly portable and cost-effective third-generation sequencing instrument, but has not been used for Ab repertoire sequencing due to its high error rate (approximately 1/10 bases). Here, we applied nanopore sequencing to single-domain Ab (sdAb) repertoires and phage-displayed sdAb libraries. We show that despite low overall data fidelity, sdAb sequences could be reconstructed above a frequency threshold (∼100 copies); however, distinguishing clonal sdAb variants was not always possible. The data quality was sufficient to enable rapid identification of antigen-specific sdAb sequences enriched during panning of phage display libraries, obviating the need for screening single clones

Nonlinear stability of spatially-periodic traveling-wave solutions of systems of reaction diffusion equations

Using spatial domain techniques developed by the authors and Myunghyun Oh in the context of parabolic conservation laws, we establish under a natural set of spectral stability conditions nonlinear asymptotic stability with decay at Gaussian rate of spatially periodic traveling-waves of systems of reaction diffusion equations. In the case that wave-speed is identically zero for all periodic solutions, we recover and slightly sharpen a well-known result of Schneider obtained by renormalization/Bloch transform techniques; by the same arguments, we are able to treat the open case of nonzero wave-speeds to which Schneider's renormalization techniques do not appear to appl

Static and Dynamic Software Quality Metric Tools

The ability to detect and predict poor software quality is of major importance to software engineers, managers, and quality assurance organizations. Poor software quality leads to increased development costs and expensive maintenance. With so much attention on exacerbated budgetary constraints, a viable alternative is necessary. Software quality metrics are designed for this purpose. Metrics measure aspects of code or PDL representations, and can be collected and used throughout the life cycle [RAMC85]

Geographic disparities in colorectal cancer survival

© 2009 Henry et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Measurement of Ada Throughout the Software Development Life Cycle

Quality enhancement has now become a major factor in software production. Software metrics have demonstrated their ability to predict source code complexity at design time and to predict maintainability of a software system from source code. Obviously metrics can assist software developers in the enhancement of quality. Tools which automatically generate metrics for Ada are increasing in popularity. This paper describes an existing tool which produces software metrics for Ada that may be used throughout the software development life cycle. This tool, while calculating established metrics, also calculates a new structure metric that is designed to capture communication interface complexity. Measuring designs written using Ada as a PDL allows designers early feedback on possible problem areas in addition to giving direction on testing strategies

Matrix Multiplication via Matrix Groups

In 2003, Cohn and Umans proposed a group-theoretic approach to bounding the exponent of matrix multiplication. Previous work within this approach ruled out certain families of groups as a route to obtaining ? = 2, while other families of groups remain potentially viable. In this paper we turn our attention to matrix groups, whose usefulness within this framework was relatively unexplored. We first show that groups of Lie type cannot prove ? = 2 within the group-theoretic approach. This is based on a representation-theoretic argument that identifies the second-smallest dimension of an irreducible representation of a group as a key parameter that determines its viability in this framework. Our proof builds on Gowers\u27 result concerning product-free sets in quasirandom groups. We then give another barrier that rules out certain natural matrix group constructions that make use of subgroups that are far from being self-normalizing. Our barrier results leave open several natural paths to obtain ? = 2 via matrix groups. To explore these routes we propose working in the continuous setting of Lie groups, in which we develop an analogous theory. Obtaining the analogue of ? = 2 in this potentially easier setting is a key challenge that represents an intermediate goal short of actually proving ? = 2. We give two constructions in the continuous setting, each of which evades one of our two barriers

Matrix multiplication via matrix groups

In 2003, Cohn and Umans proposed a group-theoretic approach to bounding the exponent of matrix multiplication. Previous work within this approach ruled out certain families of groups as a route to obtaining $\omega = 2$, while other families of groups remain potentially viable. In this paper we turn our attention to matrix groups, whose usefulness within this framework was relatively unexplored. We first show that groups of Lie type cannot prove $\omega=2$ within the group-theoretic approach. This is based on a representation-theoretic argument that identifies the second-smallest dimension of an irreducible representation of a group as a key parameter that determines its viability in this framework. Our proof builds on Gowers' result concerning product-free sets in quasirandom groups. We then give another barrier that rules out certain natural matrix group constructions that make use of subgroups that are far from being self-normalizing. Our barrier results leave open several natural paths to obtain $\omega = 2$ via matrix groups. To explore these routes we propose working in the continuous setting of Lie groups, in which we develop an analogous theory. Obtaining the analogue of $\omega=2$ in this potentially easier setting is a key challenge that represents an intermediate goal short of actually proving $\omega = 2$. We give two constructions in the continuous setting, each of which evades one of our two barriers.Comment: 15 page

Curricular Satisfaction Levels of National Athletic Trainers\u27 Association- Accredited Postprofessional Athletic Training Graduates

Context: Academic programs rely on outcomes assessments to determine if changes in the curriculum are necessary. Objective: To examine the overall satisfaction levels of graduates (2005-2006) of National Athletic Trainers\u27 Association-accredited postprofessional athletic training education programs as related to the 2002 Standards and Guidelines for Development and Implementation of NATA-Accredited PostProfessional Graduate Athletic Training Education Programs. Design: Original survey instrument and demographic questionnaire. Setting: Online survey instrument. Patients or Other Participants: Of 211 survey recipients, 123 returned surveys (58.29% response rate). Main Outcome Measure(s): Demographic information and satisfaction levels in 10 standard areas (depth of learning, breadth of learning, critical thinking, instructor availability, theoretic basis, writing skills, scholarly growth, community return, leadership, and overall program satisfaction) were obtained. Satisfaction scores were categorized into 10 percentage brackets (eg, 80%-89%) for each standard area. Results: No differences were noted in relation to any of the standard satisfaction areas for evaluation of time off from school. However, graduates who required more than the allotted amount of time to complete their degree were less satisfied in the areas of depth of learning (P = .027), breadth of learning (P = .001), instructor availability (P = .005), writing (P = .022), and overall program satisfaction (P = .016). Conclusions: Graduates were generally satisfied across all areas of their didactic curriculum. However, satisfaction levels were affected if graduates required more than the allotted amount of time to complete their degrees