Using directional curvatures to visualize folding patterns of the GTM projection manifolds

In data visualization, characterizing local geometric properties of non-linear projection manifolds provides the user with valuable additional information that can influence further steps in the data analysis. We take advantage of the smooth character of GTM projection manifold and analytically calculate its local directional curvatures. Curvature plots are useful for detecting regions where geometry is distorted, for changing the amount of regularization in non-linear projection manifolds, and for choosing regions of interest when constructing detailed lower-level visualization plots.

Research with in-built replications:comment and further suggestions for replication research

This brief commentary on the paper Designing Research with In-built Differentiated Replication expands on concerns about a lack of replication research by focusing on three key questions of continuous importance: Why should researchers conduct more replication research? Why do so few researchers conduct replication studies? What can researchers do to add more studies? This paper identifies barriers preventing replication related to the scientific system, the replication researcher, and the initial research. Suggestions include publishing all papers electronically along with reviews; authors taking steps to encourage replications of their work; and editors inviting replications of important papers. The scientific community should establish a replication index as a measure of output quality. © 2012 Elsevier Inc.

What are tests for? The implications of stuttering steps along the patient pathway

This article explores the implications of how US family physicians make decisions about ordering diagnostic tests for their patients. Data is based on a study of 256 physicians interviewed after viewing a video vignette of a presenting patient. The qualitative analysis of 778 statements relating to trustworthiness of evidence for their decision making, the use of any kind of technology and diagnostic testing suggests a range of internal and external constraints on physician decision making. Test-ordering for family physicians in the United States is significantly influenced by both hidden cognitive processes related to the physician's calculation of patient resources and a health insurance system that requires certain types of evidence in order to permit further tests or particular interventions. The consequence of the need for physicians to meet multiple forms of proof that may not always relate to relevant treatment delays a diagnosis and treatment plan agreed not only by the physician and patient but also the insurance company. This results in a patient journey that is made up of stuttering steps to a confirmed diagnosis and treatment undermining patient-centred practice, compromising patient care, constraining physician autonomy and creating additional expense. © 2014 Elsevier Ltd.