Saccadic Predictive Vision Model with a Fovea

We propose a model that emulates saccades, the rapid movements of the eye, called the Error Saccade Model, based on the prediction error of the Predictive Vision Model (PVM). The Error Saccade Model carries out movements of the model's field of view to regions with the highest prediction error. Comparisons of the Error Saccade Model on Predictive Vision Models with and without a fovea show that a fovea-like structure in the input level of the PVM improves the Error Saccade Model's ability to pursue detailed objects in its view. We hypothesize that the improvement is due to poorer resolution in the periphery causing higher prediction error when an object passes, triggering a saccade to the next location.Comment: 10 pages, 6 figure, Accepted in International Conference of Neuromorphic Computing (2018

Periods, Lefschetz numbers and entropy for a class of maps on a bouquet of circles

We consider some smooth maps on a bouquet of circles. For these maps we can compute the number of fixed points, the existence of periodic points and an exact formula for topological entropy. We use Lefschetz fixed point theory and actions of our maps on both the fundamental group and the first homology group.Comment: 19 pages, 2 figure

Interior Point Methods for Massive Support Vector Machines

We investigate the use of interior point methods for solving quadratic programming problems with a small number of linear constraints where the quadratic term consists of a low-rank update to a positive semi-de nite matrix. Several formulations of the support vector machine t into this category. An interesting feature of these particular problems is the vol- ume of data, which can lead to quadratic programs with between 10 and 100 million variables and a dense Q matrix. We use OOQP, an object- oriented interior point code, to solve these problem because it allows us to easily tailor the required linear algebra to the application. Our linear algebra implementation uses a proximal point modi cation to the under- lying algorithm, and exploits the Sherman-Morrison-Woodbury formula and the Schur complement to facilitate e cient linear system solution. Since we target massive problems, the data is stored out-of-core and we overlap computation and I/O to reduce overhead. Results are reported for several linear support vector machine formulations demonstrating the reliability and scalability of the method

Ghost of 0.7%: Origins and Relevance of the International Aid Target

The international goal for rich countries to devote 0.7% of their national income to development assistance has become a cause célèbre for aid activists and has been accepted in many official quarters as the legitimate target for aid budgets. The origins of the target, however, raise serious questions about its relevance. First, the 0.7% target was calculated using a series of assumptions that are no longer true, and justified by a model that is no longer considered credible. When we use essentially the same method used to arrive at 0.7% in the early 1960s and apply today’s conditions, it yields an aid goal of just 0.01% of rich-country GDP for the poorest countries and negative aid flows to the developing world as a whole. We do not claim in any way that this is the 'right' amount of aid, but only that this exercise lays bare the folly of the initial method and the subsequent unreflective commitment to the 0.7% aid goal. Second, we document the fact that, despite frequent misinterpretation of UN documents, no government ever agreed in a UN forum to actually reach 0.7%—though many pledged to move toward it. Third, we argue that aid as a fraction of rich country income does not constitute a meaningful metric for the adequacy of aid flows. It would be far better to estimate aid needs by starting on the recipient side with a meaningful model of how aid affects development. Although aid certainly has positive impacts in many circumstances, our quantitative understanding of this relationship is too poor to accurately conduct such a tally. The 0.7% target began life as a lobbying tool, and stretching it to become a functional target for real aid budgets across all donors is to exalt it beyond reason. That no longer makes any sense, if it ever did.aid, foreign aid, development, mdg, mdgs, millennium development goals, oda, united nations, un, overseas development assistance, africa