Within-Document Retrieval: A User-Centred Evaluation of Relevance Profiling

We present a user-centred, task-oriented, comparative evaluation of two within-document retrieval tools. ProfileSkim computes a relevance profile for a document with respect to a query, and presents the profile as an interactive bar graph. FindSkim provides similar functionality to the web browser “Find” command. A novel simulated work task was devised, where participants are asked to identify (index) relevant pages of an electronic book, given topics from the existing book index. The original book index provides the ground truth, against which the indexing results of the participants can be compared. We confirmed a major hypothesis, namely ProfileSkim proved significantly more efficient than Find-Skim, as measured by time for task. The study indicates that ProfileSkim was as least as effective as FindSkim in identifying relevant pages, as measured by traditional information retrieval measures, and there is some evidence that ProfileSkim is a precision-enhancing tool. Based on qualitative data from questionnaires, we also provide strong evidence to support our conjecture that the participants would be more satisfied when using ProfileSkim than FindSkim. The experimental study confirmed the potential of relevance profiling for improving within-document retrieval. Relevance profiling should prove highly beneficial for users trying to identify relevant information within long documents.     

The Perspectives of Women and Their Health-Care Providers Regarding Using an ECA to Support Mode of Birth Decisions

This study used focus groups to assess the feasibility and acceptability of adapting an Embodied Conversational Agent (ECA) to support decision-making about mode of birth after previous cesarean. Twelve women with previous cesareans, and eight prenatal providers at an academic, tertiary-care medical center, viewed a prototype ECA and were asked to share feedback on the potential role in helping women prepare for decision-making. Both groups felt that although it was somewhat “robot-like,” the ECA could provide easy access to information for patients and could augment the visit with providers. Future work is needed to improve ECA visual appeal and clarify the role and timing for utilization of decision aids using ECA technology to enhance the shared decision-making process.     

Superstar effects on royalty income in a performing rights organization

This paper examines the economic accomplishments of individual members in a Performing Rights Organization (PRO), sometimes referred to as a Performing Rights Society. Today, there is the growing importance of intellectual property and copyright protection for authors and creators of literary, dramatic, musical, artistic and other intellectual works. The digital age has placed added pressure on songwriters, lyricists and composers in their ability to derive economic benefits from their intellectual creativity in the form of a copyright. Copyright laws protect and enable the creation of music by allowing authors and composers to license the control and use of their creations, and receive compensation in the form of royalty payments for their work. The PROs license, collect and distribute royalty payments for non-dramatic public performances of copyrighted musical works created and owned by its members or affiliates. In this paper, skewness and heavy tail of returns in the form of member royalty payments are estimated using the skew-normal and skew-t distributions in a parametric approach. We found strong evidence of the so-called ‘superstar effect’ in which the average royalty payment made by a PRO is still dominated by extreme outcomes, and relatively few members earned a substantial share of royalty payments from blockbuster hits that have endured over time. There is little evidence of smaller niche members dominating or replacing the ‘superstars.’ Economists and others will benefit from this empirical study which emphasizes a new understanding of the music industry from a PRO, member royalty payment and performance copyright perspective.     

The Academic Spin-Offs as an Engine of Economic Transition in Eastern Europe. A Path-Dependent Approach

The paper questions some of the premises in studying academic spin-offs in developed countries, claiming that when taken as characteristics of ‘academic spin-offs per se,’ they are of little help in understanding the phenomenon in the Eastern European countries during the transitional and post-transitional periods after 1989. It argues for the necessity of adopting a path-dependent approach, which takes into consideration the institutional and organisational specificities of local economies and research systems and their evolution, which strongly influence the patterns of spin-off activity. The paper provides new findings and original arguments in support of Balazs’ seminal theses (Balazs 1995, 1996) about the emergence of academic spin-offs during the early transition. It reveals key economic and policy mechanisms bearing on academic entrepreneurship in Eastern Europe, such as the tensions between economic and political nomenclatures of former Communist Parties, where the dismantling or preservation of the power of political nomenclature resulted in different patterns of development—rapid reforms in the ‘first wave’ of EU accession countries or the establishment of rent-seeking and assets-stripping economies in countries like Bulgaria and Romania, making the transition period especially difficult. In the latter, a specific economic environment emerged, unknown in Western Europe and in the ‘champions’ of transition—such as suppression of the authentic entrepreneurship in a number of economic sectors, disintegration of corporate structures, etc. Thus, the paper reveals the common ground behind the two conflicting tendencies in post-socialist academic spin-offs, partially outlined in other research (Simeonova 1995; Pavlova 2000): as an authentic form of academic entrepreneurship grasping the opportunities opened up by the economic crisis and compensating failures in science and technology policy on the one hand, and as specific rent-seeking strategy draining valuable public assets on the other (the latter, in turn, boosting the negative attitudes in local scientific communities). The paper provides new findings about the evolution of the academic spin-offs in Bulgaria along the two polar trends and their positive and negative repercussions on parent research institutions. The results were achieved in the PROKNOW Project, EC 6th Framework Program.     

Identification of a nonlinear dynamic biological model using the dominant parameter selection method

The identification of nonlinear models sometimes encounters problems because of the limited amount of available measurements in combination with a large number of uncertain model parameters to be identified. E.g., the determination of the chemical composition of a lettuce crop is a rather expensive procedure; thus the number of experimental measurements is limited. As a result, the number of parameters of the dynamic model that can be successively identified is also limited, and the subset of the parameters to be identified must be chosen in a reasonable way.Parameter estimation for an extended nonlinear three-state model for lettuce growth in greenhouses is presented in this paper. The varying structural nitrogen concentration and water contents are the new elements included in the model. The dominant parameter selection (DPS) method was used to select a suitable set of identifiable parameters. The resulting calibrated model predicts quite well the experimental data which also include observations with severe nitrogen stress.     

Why Here and Why Now? Teacher Motivations for Unionizing in a New Orleans Charter School

The rigidity of teachers unions has been given as a primary reason for their lack of representation among America’s rapidly growing, although still relatively small, charter school sector. In the case of post-Hurricane Katrina New Orleans, the city rapidly converted from a union-backed teacher workforce to a largely nonunionized charter school workforce in the years following state takeover and charter conversion. This makes the recent emergence of two single-school unions in charter schools there worthy of study. As the teachers attempt to organize single-school unions in a nearly all charter school system, what are their motivations? This case study of one of New Orleans’ emerging charter school unions found that pay inequities, job insecurity, a lack of teacher voice in school-level decisions, and a culture of compliance, all motivated teachers to seek unionization. Teachers hoped to promote equity and teacher involvement with their union, but the organizing effort did strain some relationships, particularly those involving middle management.     

Systematic characterization of degas-driven flow for poly(dimethylsiloxane) microfluidic devices

Degas-driven flow is a novel phenomenon used to propel fluids in poly(dimethylsiloxane) (PDMS)-based microfluidic devices without requiring any external power. This method takes advantage of the inherently high porosity and air solubility of PDMS by removing air molecules from the bulk PDMS before initiating the flow. The dynamics of degas-driven flow are dependent on the channel and device geometries and are highly sensitive to temporal parameters. These dependencies have not been fully characterized, hindering broad use of degas-driven flow as a microfluidic pumping mechanism. Here, we characterize, for the first time, the effect of various parameters on the dynamics of degas-driven flow, including channel geometry, PDMS thickness, PDMS exposure area, vacuum degassing time, and idle time at atmospheric pressure before loading. We investigate the effect of these parameters on flow velocity as well as channel fill time for the degas-driven flow process. Using our devices, we achieved reproducible flow with a standard deviation of less than 8% for flow velocity, as well as maximum flow rates of up to 3 nL∕s and mean flow rates of approximately 1-1.5 nL∕s. Parameters such as channel surface area and PDMS chip exposure area were found to have negligible impact on degas-driven flow dynamics, whereas channel cross-sectional area, degas time, PDMS thickness, and idle time were found to have a larger impact. In addition, we develop a physical model that can predict mean flow velocities within 6% of experimental values and can be used as a tool for future design of PDMS-based microfluidic devices that utilize degas-driven flow.