Identification of individuals and groups in a public goods experiment

Revealing the identities of contributors has been shown to increase cooperation in public goods games. In this paper we experimentally investigate whether this finding holds true when decisions are made by groups rather than individuals. We distinguish between groups in which members can discuss face-to-face to reach a decision and groups in which members communicate via computer chat. The results confirm the positive effect of identification on cooperation among individuals. For groups, however, we only find a small and temporary effect of identification, irrespective of the type of communication. The reason for this is that the sensitivity to others’ opinions plays an important role for individual decisions but not for group decisions

Pragmatism, Praxis, and Predictive Theory

Jason, Stevens, Ram, Miller, Beasley, and Gleason (2016) invoke particular views of “true science” (p. 4) and “hard science” (p. 7) in their call for “more rigorous and predictive theory” (p. 21) in community psychology. They explain that a theory (as opposed to a framework or a model) makes predictions about causal relationships that are specific enough that they can be empirically tested and either verified or falsified under various conditions. They claim that by moving from frameworks guiding inquiry and action toward unambiguous predictive theories, the field will be “of greater value to the larger scientific community” (p. 3) and could “go a long way toward making significant progress in understanding how complex systems and the contexts in which people live can influence their lives” (p. 7). Their article is valuable for the debate it will produce by staking out such a clear position on a topic on which, as the authors note, viewpoints vary. In my view, the central thrust of their article – away from a pragmatic action orientation to inquiry and toward testing of predictive theories – could actually hamper the field’s progress toward its goals, if adopted more broadly in the field of community psychology

Pragmatism, Praxis, and Predictive Theory

Jason, Stevens, Ram, Miller, Beasley, and Gleason (2016) invoke particular views of “true science” (p. 4) and “hard science” (p. 7) in their call for “more rigorous and predictive theory” (p. 21) in community psychology. They explain that a theory (as opposed to a framework or a model) makes predictions about causal relationships that are specific enough that they can be empirically tested and either verified or falsified under various conditions. They claim that by moving from frameworks guiding inquiry and action toward unambiguous predictive theories, the field will be “of greater value to the larger scientific community” (p. 3) and could “go a long way toward making significant progress in understanding how complex systems and the contexts in which people live can influence their lives” (p. 7). Their article is valuable for the debate it will produce by staking out such a clear position on a topic on which, as the authors note, viewpoints vary. In my view, the central thrust of their article – away from a pragmatic action orientation to inquiry and toward testing of predictive theories – could actually hamper the field’s progress toward its goals, if adopted more broadly in the field of community psychology

New methods for assessing the impact of traffic safety countermeasures.

This paper investigates new methods for assessing the impact of traffic safety countermeasures on the number of accidents or injuries. The primary aim of this paper is to show in general how statistical methods that take development over time into account may be used when assessing the impact on traffic safety data. A secondary aim is to specifically investigate the effect of a change in the police accident reporting routine in 1997 on the injury classification. A salient characteristic in most monthly traffic safety data is a fluctuating trend and seasonal pattern. Some of the fluctuation can be explained, but in order to have a reliable assessment of the countermeasures the evaluation methods have to capture this fluctuation. So-called State Space models provide a framework, where these characteristics can be investigated and modelled explicitly. The change in the police reporting practice lead in 1998 to a 49% [35%; 60%] decrease in the reported number of head injuries in Copenhagen and in 1997 to a 37 % [27%, 46%] decrease outside Copenhagen. An estimate of the actual traffic safety in 1998 measured in the number of serious injuries could be the reported number corrected by an additional 670 injuries due to this change in the reporting

Learning From Coalitions' Efforts to Promote Equity and Justice.

Coalitions and collaboratives are working to address many of the most pressing contemporary health and social issues. The articles in this special issue provide numerous insights into these complex collaborative processes across different contexts and focal issues. All emphasize and scrutinize the strategies that groups are using in their work. These strategies seek to navigate not only conventional notions of effectiveness but also the challenges of pursuing greater equity and justice. In this concluding article, we distill some of the key insights from these articles as a collective. This special issue on collaborating for equity and justice can serve as a launching point for new efforts by coalitions and researchers pursuing policy, systems, and structural changes, particularly those intent on addressing root causes of health and social disparities

Automated System for Early Breast Cancer Detection in Mammograms

The increasing demand on mammographic screening for early breast cancer detection, and the subtlety of early breast cancer signs on mammograms, suggest an automated image processing system that can serve as a diagnostic aid in radiology clinics. We present a fully automated algorithm for detecting clusters of microcalcifications that are the most common signs of early, potentially curable breast cancer. By using the contour map of the mammogram, the algorithm circumvents some of the difficulties encountered with standard image processing methods. The clinical implementation of an automated instrument based on this algorithm is also discussed

Affine registration of multispectral images of historical documents for optimized feature recovery

Multispectral (MSI) imaging of historical documents can recover lost features, such as text or drawings. This technique involves capturing multiple images of a document illuminated using different wavelengths of light. The images created must be registered in order to ensure optimal results are produced from any subsequent image processing techniques. However, the images may be misaligned due to the presence of optical elements such as filters, or because they were acquired at different times or because the images were captured from different copies of the documents . There is little prior work or information available about which image registration techniques are most appropriate. Image registration of multispectral images is challenging as the illumination changes for each image and the features visible in images captured at different wavelengths may not appear consistently throughout the image sequence. Here, we compare three image registration techniques: two based on similarity measures and a method based on phase correlation. These methods are characterized by applying them to realistic surrogate images and then assessed on three different sets of real multispectral images. Mutual information is recommended as a measure for affine image registration when working with multispectral images of documentary material as it was proven to be more robust than the other techniques tested