The New Theory of Strategic Voting

This is an analysis of strategic voting under qualified majority voting. Existing formal analyses of the plurality rule predict complete coordination of strategic voting: a strict interpretation of Duverger's Law. This conclusion is rejected. Unlike previous models, the popular support for each option is not commonly certain. Agents base their vote on both public and private signals of popular support. When private signals are the main source of information, the uniquely stable equilibrium entails only limited strategic voting and hence partial coordination. This is due to the surprising presence of negative feedback --- strategic voting is a self-attenuating phenomenon. The theory leads to the conclusion that multi-candidate support in a plurality electoral system is perfectly consistent with rational voting behaviour.

Dynamic government performance: honeymoons and crises of confidence

We use a formal theoretical framework to explore the interplay between a government's longevity and its performance. Ministers perform well when their careers are valuable; this is so when the government's duration is expected to be long; the government's survival depends on its popularity; and, finally, that popularity depends on its ministers performance. The feedback loop between performance and longevity means that multiple rational-expectations equilibria can arise: Ministers work hard for a popular government, but divert efforts elsewhere if they believe the government is doomed; these alternatives are both self-fulfilling prophecies. However, the presence of (perhaps small) random events that buffet the performance and popularity of a government is sufficient to pin down a unique equilibrium. We explore the dynamics that arise: A crisis of confidence involving the rapid collapse of a government's performance is sparked when a sequence of negative shocks push the popularity of the government below a unique critical threshold

Leading the Party:Coordination, Direction, and Communication

Party activists face a coordination problem: a critical mass (a barrier tocoordination) must advocate a single policy alternative if the party is tosucceed. The need for direction is the degree to which the merits of thealternatives respond to the underlying mood of the party. An individual'sability to assess the mood is his sense of direction. These factors combine toform an index of both the desirability and the feasibility of leadership: wecall this index Michels' Ratio. A sovereign party conference gives way toleadership by an individual or oligarchy if and only if Michels' Ratio issufficiently high. Leadership enhances the clarity of intra-partycommunication, but weakens the response of policy choices to the party'smood.

The Qualities of Leadership:Direction, Communication, and Obfuscation

Party activists wish to (i) advocate the best policy and yet (ii) unify behind a commonparty line. An activist's understanding of his environment is based on the speeches ofparty leaders. A leader's influence, measured by the weight placed on her speech,increases with her judgement on policy (sense of direction) and her ability to conveyideas (clarity of communication). A leader with perfect clarity of communication enjoysgreater influence than one with a perfect sense of direction. Activists can choose howmuch attention to pay to leaders. A necessary condition for a leader to monopolize theagenda is that she is the most coherent communicator. Sometimes leaders attract moreattention by obfuscating their messages. A concern for party unity mitigates thisincentive; when activists emphasize following the party line, they learn more about theirenvironment.

Concepts of perceptual significance for composition and reproduction of explorable surround sound fields

Recent work in audio and visual perception suggests that, over and above sensory acuities, exploration of an environment is a most powerful perceptual strategy. For some uses, the plausibility of artificial sound environments might be dramatically improved if exploratory perception is accommodated. The composition and reproduction of spatially explorable sound fields involves a different set of problems from the conventional surround sound paradigm, developed to display music and sound effects to an essentially passive audience. This paper is based upon contemporary models of perception and presents proposals for additional spatial characteristics beyond classical concepts of three-dimensional positioning of virtual objects

Determinants of product lines

We study the determinants of product lines in a multi-product Cournot model which allows for cost asymmetries and which eliminates strategic motivations (such as a desire to soften competition) for product-line choice. We identify two distinct forces that lead firms to offer multiple qualities. We then investigate how the interaction of asymmetric competition with these forces shapes equilibrium product lines. Our model predicts a rich variety of possible outcomes, ranging from headto- head competition (in which all firms offer all products) to complete separation of product lines (so that no product is offer by two or more firms) and including the intermediate case of partial separation. In an international trade context, we predict whether a disadvantaged foreign producer will specialize in higher or lower qualities. If cost factors are the main drivers of quality-based discrimination (so that there are decreasing returns to quality) then foreign firms sell only lower qualities. However, if demand factors are the main drivers (so that, other things equal, the demand for higher qualities is less elastic) then foreign firms sell only high qualities

The undergraduate research apprenticeship - improving the relevance of science teaching through authentic research experience.

The undergraduate experience is arguably the most important in shaping the future career trajectories of students. It is here that early exposure to the widest possible range of disciplines and practical experiences will have the most impact. In the face of a reduction in the number of students entering both undergraduate science and research as a career option, we must urgently initiate strategies to engage and retain students in science. This can be achieved by a research experience in a ‘mentored apprenticeship model’ in the context of an authentic laboratory/field during their formative undergraduate years. It is widely acknowledged that an interactive, enquiry-based approach to learning provides the most meaningful and lasting learning experience for students. It is similarly accepted that, within science, undergraduate research experiences are pivotal in providing context to student learning and providing a true sense of what it means to be a 'scientist'. In this discussion forum we will summarise research-based experiences currently available for Bachelor of Science (BSc) students at The University of Queensland (UQ). We will then look in detail at a proposed new ‘mentored apprenticeship model’, being examined for introduction into the UQ BSc from 2008 following the recent major review. The proposed model builds on the existing UQ Advanced Study Program in Science combined with the University of Michigan’s Undergraduate Research Opportunity Program and aims to: • achieve an increased level of student engagement to complement other strategies for motivating students who are in large first year classes • show students the functional/practical relevance of the core content of their course material • provide students with a personal experience of doing science so that they can plan their future studies from a more informed perspective • minimize the attrition rate from the first year science cohort • provide a mentored cohort experience to engage and support under-represented groups such as indigenous and international students • actively build on the tremendous investment in institutes at UQ by increasing the direct involvement of these research academics in the undergraduate science program (for example, places for 25 students have already been committed by one of the UQ research institutes) • increase the number of students proceeding to postgraduate education as the next step to a worthwhile and personally rewarding career trajectory in science. The proposed ‘mentored apprenticeship model’ provides a step-wise approach to a student’s growth as an apprentice scientist. As undergraduates progress through their degree-program their learning experiences in science should also progress closer and closer to those of a ‘scientist’ until, on graduation, they are fully-prepared for their science-related career. The new model achieves this through establishing strong working partnerships between students and research groups, supplementing traditional practical components of undergraduate courses by ‘doing’ more science and providing students with an opportunity to talk more about science. Within this forum participants will be asked to explore: • How are the theoretical frameworks of enquiry-based learning being translated into practical applications? • What are the outcomes of an undergraduate research opportunity? • How do we assess this learning? • What are the experiences of other institutions – how have they met the challenge of an authentic research experience, in a research-intensive university, for large numbers of students? • Are there discipline-specific variations to these approaches

Modulational instability criteria for two-component Bose-Einstein condensates

The stability of colliding Bose-Einstein condensates is investigated. A set of coupled Gross-Pitaevskii equations is thus considered, and analyzed via a perturbative approach. No assumption is made on the signs (or magnitudes) of the relevant parameters like the scattering lengths and the coupling coefficients. The formalism is therefore valid for asymmetric as well as symmetric coupled condensate wave states. A new set of explicit criteria is derived and analyzed. An extended instability region, in addition to an enhanced instability growth rate is predicted for unstable two component bosons, as compared to the individual (uncoupled) state.Comment: 4 pages, 1 figur

Promoting deep learning through design - discussion, student activity and assessment

There is widespread evidence that Australia is currently facing falling student participation rates in science and mathematics subjects at secondary school and university undergraduate levels. The future implications of this science-deficit are widely acknowledged. Unfortunately, science teaching itself is also widely seen as being dull, too content-heavy, delivered to mass-audiences and assessed in ways promoting surface approaches to learning. To address these issues, and issues relating to the apparent lack of challenge for very able students in their first year at university, The University of Queensland developed the Advanced Study Program in Science (ASPinS). This initiative offers an enhanced learning experience to a select group of high-achieving students in addition to their existing undergraduate study in a Science-related degree program. ASPinS offers these students the opportunity to interact with leading research scientists, broaden their understanding of important scientific issues, experience new interactive learning opportunities, undertake research projects and obtain an authentic insight into science as a career. This presentation, however, will only focus on the unique first year course offered within the 3 year ASPinS experience – BIOL1017 “Perspectives in Science”. In this course students are encouraged to think about important current scientific issues from different perspectives – both scientific and non-scientific. Panels of expert scientists use their knowledge and experience to present real scientific issues for students to examine and discuss. These panel discussions cover a spectrum of medical, environmental and social issues, covering different viewpoints and possible solutions. Combining this effective panel model with an array of student-led activities provides an ideal environment for learning. Students are made to apply their new knowledge, discuss issues and construct thoughts, opinions and products – depending on the specifically designed activities. Relevant assessment tasks include group-writing activities and oral presentations which enable students to demonstrate their learning through authentic contexts that are carefully designed to influence the way students learn. Authentic assessment tasks enable students to see a purpose for the product (assessment) they are producing while at the same time enabling them to synthesise the various scientific ‘facts’ and issues they have been discussing. This level of assessment activity, by its nature, encourages higher-order learning. Student evaluations have consistently confirmed that the key to the success of each Module within the course lies in the breadth of speakers selected to represent the different angles associated with the topic under discussion and the related activities and assessment tasks. The findings indicate that students value the opportunity to explore the multi-disciplinary nature of science-related issues and to actually discuss the issues. The “Perspectives in Science” course is a model for the success of combining teaching and learning theory and scholarship, to a particular set of objectives, to create a highly effective learning environment and a meaningful student experience

Analysis of some global optimization algorithms for space trajectory design

In this paper, we analyze the performance of some global search algorithms on a number of space trajectory design problems. A rigorous testing procedure is introduced to measure the ability of an algorithm to identify the set of ²-optimal solutions. From the analysis of the test results, a novel algorithm is derived. The development of the novel algorithm starts from the redefinition of some evolutionary heuristics in the form of a discrete dynamical system. The convergence properties of this discrete dynamical system are used to derive a hybrid evolutionary algorithm that displays very good performance on the particular class of problems presented in this paper