Marker effects and examination reliability: a comparative exploration from the perspectives of generalizability theory, Rasch modelling and multilevel modelling

This study looked at how three different analysis methods could help us to understand rater effects on exam reliability. The techniques we looked at were: generalizability theory (G-theory) item response theory (IRT): in particular the Many-Facets Partial Credit Rasch Model (MFRM) multilevel modelling (MLM) We used data from AS component papers in geography and psychology for 2009, 2010 and 2011 from Edexcel.</p

Generalise not specialise: design implications for a national assessment bank

Within the framework of the Assessment is for Learning (AifL) programme1, two systems of national assessment are currently operating in Scottish schools: on-demand 5-14 National Assessments and the sample-based Scottish Survey of Achievement. This paper will discuss issues surrounding the design of an assessment bank intended to support both systems.2 It focuses in particular on the considerations underlying decisions about the structure of the shared materials database, the complex definition of an “item” that had to be adopted in order to accommodate a wide range of assessment types, the overall architecture of the wider information system, with its component databases (one being the bank) and information management subsystems, and the tensions arising from the need to accommodate the requirements of different systems of assessment while avoiding the dangers involved in data repetition and redundancy

From Chaos to Community: Two Libraries Finding a Unified Direction

In January 2013, the University System of Georgia Board of Regents consolidated a health sciences university and a predominantly undergraduate liberal arts university. Each university had its own library, and the consolidation presented several challenges to the newly formed University Libraries. One major challenge was unifying the catalog as each library follows different classification standards. National Library of Medicine call numbers and Medical Subject Headings were utilized on the Health Sciences campus, and Library of Congress call numbers and subject headings were used on the liberal arts campus. After recognizing the differences in the catalog records, the Libraries asked “Where do we go from here?” A cataloging subcommittee was formed to identify ways to consolidate bibliographic records, streamline holdings, and turn chaos into community

Longitudinal Image Analysis of Tumor/Brain Change in Contrast Uptake Induced by Radiation

This work is motivated by a quantitative Magnetic Resonance Imaging study of the differential tumor/healthy tissue change in contrast uptake induced by radiation. The goal is to determine the time in which there is maximal contrast uptake, a surrogate for permeability, in the tumor relative to healthy tissue. A notable feature of the data is its spatial heterogeneity. Zhang, Johnson, Little, and Cao (2008a and 2008b) discuss two parallel approaches to “denoise” a single image of change in contrast uptake from baseline to a single follow-up visit of interest. In this work we explore the longitudinal profile of the tumor/healthy tissue change in contrast uptake. In addition to the spatial correlation, we account for temporal correlation by jointly modeling multiple images on the individual subjects over time. We fit a two-stage model. First, we propose a longitudinal image model for each subject. This model simultaneously accounts for the spatial and temporal correlation and denoises the observed images by borrowing strength both across neighboring pixels and over time. We propose to use the area under the receiver operating characteristics (ROC) curve (AUC) to summarize the differential contrast uptake between tumor and healthy tissue. In the second stage, we fit a population model on the AUC values and estimate when it achieves the maximum

Laparoscopic Cytoreduction for Primary Advanced Ovarian Cancer

Laparoscopic-assisted cytoreduction for primary advanced ovarian cancer was found to be a feasible intervention technique with minimal morbidity

Preserve Local and Institution-Specific Data During Migration to a Network Cataloging Environment

During the fall of 2015, the Augusta University Libraries began the process of implementing Ex Libris’ nextgeneration library management solution, Alma. This process is occurring in various phases, with the initial steps being data clean-up and migration. As part of the migration process, cataloging records that are currently created and maintained by both university libraries will be migrated into a collaborative Alma network zone comprised of 29 institutions in the University System of Georgia (USG) consortium. The network zone will allow for collaborative cataloging among multiple libraries. One of the main challenges for Augusta University, however, was finding a way to preserve the libraries’ local data which included medical subject headings (MeSH) used by the health sciences library. This paper addresses the challenges faced and strategies employed by Augusta University Libraries to ensure local information was migrated from the existing Ex Libris’ Voyager traditional integrated library system (ILS) into Alma

Carbon Flux from Bio-optical Profiling Floats: Calibrating Transmissometers for Use as Optical Sediment Traps

Our mechanistic understanding of the processes controlling the ocean\u27s biological pump is limited, in part, by our lack of observational data at appropriate timescales. The “optical sediment trap” (OST) technique utilizes a transmissometer on a quasi-Lagrangian platform to collect sedimenting particles. This method could help fill the observational gap by providing autonomous measurements of particulate carbon (PC) flux in the upper mesopelagic ocean at high spatiotemporal resolution. Here, we used a combination of field measurements and laboratory experiments to test hydrodynamic and zooplankton-swimmer effects on the OST method, and we quantitatively calibrated this method against PC flux measured directly in same-platform, neutrally buoyant sediment traps (NBSTs) during 5 monthly cruises at the Bermuda Atlantic Time-series Study (BATS) site. We found a well-correlated, positive relationship (R2 = 0.66, n = 15) between the OST proxy, and the PC flux measured directly using NBSTs. Laboratory tests showed that scattering of light from multiple particles between the source and detector was unlikely to affect OST proxy results. We found that the carbon-specific attenuance of sinking particles was larger than literature values for smaller, suspended particles in the ocean, and consistent with variable carbon:size relationships reported in the literature for sinking particles. We also found evidence for variability in PC flux at high spatiotemporal resolution. Our results are consistent with the literature on particle carbon content and optical properties in the ocean, and support more widespread use of the OST proxy, with proper site-specific and platform-specific calibration, to better understand variability in the ocean biological pump