The Economics of Small Worlds

We examine a simple economic model of network formation where agents benefit from indirect relationships. We show that small-world features—short path lengths between nodes together with highly clustered link structures—necessarily emerge for a wide set of parameters

Rethinking 'multi-user': an in-the-wild study of how groups approach a walk-up-and-use tabletop interface

Multi-touch tabletops have been much heralded as an innovative technology that can facilitate new ways of group working. However, there is little evidence of these materialising outside of research lab settings. We present the findings of a 5-week in-the-wild study examining how a shared planning application – designed to run on a walk-up- and-use tabletop – was used when placed in a tourist information centre. We describe how groups approached, congregated and interacted with it and the social interactions that took place – noting how they were quite different from research findings describing the ways groups work around a tabletop in lab settings. We discuss the implications of such situated group work for designing collaborative tabletop applications for use in public settings

Leishmania manipulation of sand fly feeding behavior results in enhanced transmission.

In nature the prevalence of Leishmania infection in whole sand fly populations can be very low (<0.1%), even in areas of endemicity and high transmission. It has long since been assumed that the protozoan parasite Leishmania can manipulate the feeding behavior of its sand fly vector, thus enhancing transmission efficiency, but neither the way in which it does so nor the mechanisms behind such manipulation have been described. A key feature of parasite development in the sand fly gut is the secretion of a gel-like plug composed of filamentous proteophosphoglycan. Using both experimental and natural parasite-sand fly combinations we show that secretion of this gel is accompanied by differentiation of mammal-infective transmission stages. Further, Leishmania infection specifically causes an increase in vector biting persistence on mice (re-feeding after interruption) and also promotes feeding on multiple hosts. Both of these aspects of vector behavior were found to be finely tuned to the differentiation of parasite transmission stages in the sand fly gut. By experimentally accelerating the development rate of the parasites, we showed that Leishmania can optimize its transmission by inducing increased biting persistence only when infective stages are present. This crucial adaptive manipulation resulted in enhanced infection of experimental hosts. Thus, we demonstrate that behavioral manipulation of the infected vector provides a selective advantage to the parasite by significantly increasing transmission

The Economics of Small Worlds

We examine a simple economic model of network formation where agents benefit from indirect relationships. We show that small-world features - -- short path lengths between nodes together with highly clustered link structures --- necessarily emerge for a wide set of parameters.networks, small worlds

Heat in the Heartland: Climate Change and Economic Risk in the Midwest

This report offers a first step toward defining the range of potential economic consequences to the Midwest if we continue on our current greenhouse gas emissions pathway. The research combines state-of-the-art climate science projections through the year 2100 (and beyond in some cases) with empirically-derived estimates of the impact of projected changes in temperature and precipitation on the Midwest economy. The authors analyze not only those outcomes most likely to occur, but also lower-probability, higher-cost climate futures. These are the "tail risks," most often expressed here as the 1-in-20 chance something will occur. Unlike any other study to date, this report looks at climate impacts at a very geographically granular level, in some cases providing county-level results

Homophily and Long-Run Integration in Social Networks

We model network formation when heterogeneous nodes enter sequentially and form connections through both random meetings and network-based search, but with type-dependent biases. We show that there is "long-run integration," whereby the composition of types in sufficiently old nodes' neighborhoods approaches the global type distribution, provided that the network-based search is unbiased. However, younger nodes' connections still reflect the biased meetings process. We derive the type-based degree distributions and group-level homophily patterns when there are two types and location-based biases. Finally, we illustrate aspects of the model with an empirical application to data on citations in physics journals.Comment: 39 pages, 2 figure

Developing a Staged Competency Based Approach to Enterprise Creation

Entrepreneurialism is a concept which affects individuals in a range of different ways (Jones et al 2014). In this paper the authors are interested in exploring how entrepreneurial activity can improve a person's propensity to create new ventures and how educational frameworks applied in a university context can be devised to specifically support this development. Building on previous work (Churchill and Lewis, 1983; Gartner, 1985; Draycott and Rae, 2011; Lackéus et al 2016), the Authors will explore a range of frameworks to identify elements which are useful and then develop these to propose a model which, they believe, will support the facilitation of experiential entrepreneurship education to show tangible results in the creation and growth (Blank and Dorf, 2010) of new ventures. The authors believe that this is important to increase discussion surrounding the development of experiential entrepreneurial education programmes (Jones et al 2014, Lackéus et al 2016), their impact (Kozlinska, 2016) and the ways in which university-based entrepreneurship programs, incorporating real-life venture creation, can bridge the gap (Lackéus and Williams Middleton, 2015) between entrepreneurship education and enterprise creation within the university environment. The paper discusses how the focal competence needed depends on the stage of the business and not necessarily on the academic level, mapping these to the EntreComp: The Entrepreneurship Competence Framework (Bacigalupo et al., 2016). To achieve this the paper will propose a staged, process-based approach to entrepreneurial education design which draws on the work of Kuratko and Morris (2015) to break the entrepreneurial effort into specific stages, or steps. This staged framework for entrepreneurial development will map the focal competencies and skills required for each of the stages of development and with the requirements for the entrepreneurial process integrative framework. The model nine stages are: Discovery, Modeling, Startup, Existence, Survival, Success, Adaption, Independence and Exit. The first three stages bring about a robust business idea and formation which are core developments within an educational setting. The next three develop the venture and the entrepreneur into a sustainable business entity and the last three provide entrepreneurial pathways. The resulting framework provides an identifiable path for educators, researchers, managerial practice and quality assurance for the support of entrepreneurs and their businesses. In teaching, the approach should be structured around the frameworks to capture the full content of entrepreneurship as opposed to a more narrow focus on case studies, business plans, and other experiential exercises. This paper leads the educator to a more comprehensive understanding of the dynamic nature of entrepreneurship, the skills required, the processes involved, the relationship between the entrepreneur and the venture, and the stages required to achieve this. Description of the poster: This staged framework for entrepreneurial development maps the focal competencies and skills required for each of the stages of development and with the requirements for the entrepreneurial process integrative framework. The model nine stages are: Discovery, Modeling, Startup, Existence, Survival, Success, Adaption, Independence and Exit. The first three stages bring about a robust business idea and formation which are core developments within an educational setting. The next three develop the venture and the entrepreneur into a sustainable business entity and the last three provide entrepreneurial pathways. The resulting framework provides an identifiable path for educators, researchers, managerial practice and quality assurance for the support of entrepreneurs and their businesses. In teaching, the approach should be structured around the frameworks to capture the full content of entrepreneurship as opposed to a more narrow focus on case studies, business plans, and other experiential exercises