Randomness and Inference in Medical and Public Health Research

Background: The purpose of this study was to provide a basis for describing the types of randomness used and statistical inferences reported in the medical and public health research literature. Methods: A study was conducted to quantify the types of research designs and analyses used and reported in medical and public health research studies. A stratified random sample of 198 articles from three top-tier medical and public health journals was reviewed, and the presence or absence of random assignment, random sampling, p-values, and confidence intervals, as well as type of research design, were quantified. Results: Random sampling was used in 58 (29.3%) and random assignment in 21 (10.6%) articles. Most (n=125; 63.1%) research studies did not report random assignment or random sampling; however, statistical inference was applied in more than 90%. Conclusions: Results revealed a concerning overuse of statistical inference. Incorrectly applying statistical inference when not warranted has potentially damaging medical and public health consequences. Researchers should carefully consider the appropriateness of using statistical inference in medical and public health research. Key words: randomization, statistical inference, research desig

How Leaders Invest Staffing Resources for Learning Improvement

Analyzes staffing challenges that guide school leaders' resource decisions in the context of a learning improvement agenda, staff resource investment strategies that improve learning outcomes equitably, and ways to win support for differential investment

HI in Early-Type Galaxies

We briefly discuss the main differences between the HI properties of luminous and low-luminosity early-type galaxies. In luminous early-type galaxies the HI is often irregularly distributed, but in a few cases regular HI disks, of low surface density, are seen. In low-luminosity galaxies, the HI is more often in a disk with high central surface densities. This suggests a different evolution of the gas in these two groups of galaxies.Comment: To appear in the proceedings of the conference "Gas and Galaxy Evolution" (ASP Conference Series), eds. J. Hibbard, M. Rupen, and J. van Gorko

Minnesota Sentencing Guidelines

Symposium: Seventh Annual Conference of the National Association of Women Judges: Conference Presentation

Minnesota Sentencing Guidelines

Symposium: Seventh Annual Conference of the National Association of Women Judges: Conference Presentation

Community capacity

This is a visual note of a research study report on building community capacity in social care. Based on: Knapp, Martin, Bauer, Annette, Perkins, Margaret and Snell, Tom (2010) "Building community capacity: making an economic case." PSSRU Discussion Papers, DP2772. Personal Social Services Research Unit, London, UK. - Winner of the LSE Research Festival 2014 Poster prize

Application of the Empirical Mode Decomposition and Hilbert-Huang Transform to Seismic Reflection Data

Advancements in signal processing may allow for improved imaging and analysis of complex geologic targets found in seismic reflection data. A recent contribution to signal processing is the empirical mode decomposition (EMD) which combines with the Hilbert transform as the Hilbert- Huang transform (HHT). The EMD empirically reduces a time series to several subsignals, each of which is input to the same time-frequency environment via the Hilbert transform. The HHT allows for signals describing stochastic or astochastic processes to be analyzed using instantaneous attributes in the time-frequency domain. The HHT is applied herein to seismic reflection data to: (1) assess the ability of the EMD and HHT to quantify meaningful geologic information in the time and time-frequency domains, and (2) use instantaneous attributes to develop superior filters for improving the signal-to-noise ratio. The objective of this work is to determine whether the HHT allows for empirically-derived characteristics to be used in filter design and application, resulting in better filter performance and enhanced signal-to-noise ratio. Two data sets are used to show successful application of the EMD and HHT to seismic reflection data processing. Nonlinear cable strum is removed from one data set while the other is used to show how the HHT compares to and outperforms Fourier-based processing under certain conditions

New discoveries at Woolsey Mound, MC118, northern Gulf of Mexico

Woolsey Mound, a 1km-diameter carbonate-gas hydrate complex in the northern Gulf of Mexico, is the site of the Gulf’s only seafloor monitoring station-observatory in its only research reserve, Mississippi Canyon 118. Active venting, outcropping hydrate, and a thriving chemosynthetic community recommend the site for study. Since 2005, the Gulf of Mexico Hydrates Research Consortium has been conducting multidisciplinary studies to 1. Characterize the site, 2. Establish a facility for real-time monitoring-observing of gas hydrates in a natural setting, 3. Study the effects of gas hydrates on seafloor stability, 4. Establish fluid migration routes and estimates of fluid-flux at the site, 5. Establish the interrelationships between the organisms at the vent site and the association-dissociation of hydrates. A variety of novel geological, geophysical, geochemical and biological studies has been designed and conducted, some in survey mode, others in monitoring mode. Geophysical studies involving merging multiple seismic data acquisition systems accompanied by the application of custom processing techniques verify communication of surface features with deep structures. Supporting geological data derive from innovative recovery techniques. Geochemical sensors, used experimentally in survey mode, including aboard an AUV, double as monitoring devices. A suite of pore-fluid sampling devices has returned data that capture change at the site in daily increments; using only noise as an energy source, hydrophones have returned daily fluctuations in physical properties. Ever-expanding capabilities of a custom-ROV have been determined by research needs. Processing of new as well as conventional data via unconventional means has resulted in the discovery of new features…..vents, faults, benthic fauna…..and modification of others including pockmarks, hydrate outcrops, vent activity, and water-column chemical plumes. Though real-time monitoring awaits communications and power link to land, periodic data-collection reveals a carbonate-hydrate mound, part of an immensely complex hydrocarbon system

Color Confirmation of Asteroid Families

We discuss optical colors of 10,592 asteroids with known orbits selected from a sample of 58,000 moving objects observed by the Sloan Digital Sky Survey (SDSS). This is more than ten times larger sample that includes both orbital parameters and multi-band photometric measurements than previously available. We confirm that asteroid dynamical families, defined as clusters in orbital parameter space, also strongly segregate in color space. In particular, we demonstrate that the three major asteroid families (Eos, Koronis, and Themis), together with the Vesta family, represent four main asteroid color types. Their distinctive optical colors indicate that the variations in chemical composition within a family are much smaller than the compositional differences between families, and strongly support earlier suggestions that asteroids belonging to a particular family have a common origin. We estimate that over 90% of asteroids belong to families.Comment: 18 pages, color figures, accepted by A