5,309 research outputs found

    TreeRipper: towards a fully automated optical tree recognition software

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    Relationships between species, genes and genomes have been printed as trees for over a century. Whilst this may have been the best format for exchanging and sharing phylogenetic hypotheses during the 20th century, the worldwide web now provides faster and automated ways of transferring and sharing phylogenetic knowledge. However, novel software is needed to defrost these published phylogenies for the 21st century. 
TreeRipper is a command line c++ program for the fully-automated recognition of multifurcating phylogenetic trees. The program accepts a range of input image formats (PNG, JPG/JPEG, GIF, TIFF or PDF ). Then follows a number of cleaning steps to detect lines, remove node labels, patch-up broken lines and corners and detect line edges. The edge contour is then determined to detect the branch length, tip label positions and the topology of the tree. Optical Character Recognition (OCR) is used to convert the tip labels into text with the freely available tesseract-ocr software. 32% of images meeting the prerequisites for TreeRipper were successfully recognised, the largest tree had 115 leaves. 
Despite the diversity of ways phylogenies have been illustrated making the design of a fully automated tree recognition software difficult, TreeRipper is a step towards automating the digitization of past phylogenies. We also provide a dataset of 100 tree images and associated tree files for training and/or benchmarking future software.
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    Measuring efficiency when market prices are subject to adverse selection

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    In perfectly competitive markets, prices aggregate inputs and outputs into a money metric that allows production plans to be ranked by their profitability. When informational asymmetries in competitive markets lead to adverse selection, prices in these markets assume an additional role that conveys information about product quality. In the case of banking production, quality is linked to risk because prices are linked to credit quality. ; The problem of efficiency measurement is complicated by the additional role because quality varies with price and price is a decision variable of firms operating in these markets. The effect of these endogenous components of prices on financial performance is illustrated with a production-based model and a market-value model that generate "best- practice" frontiers. Unlike the standard profit function's frontier, these frontiers are not conditioned on prices so that they compare the financial performance of firms with different quality-linked prices. Hence, they identify the most efficient pricing strategies as well as the most efficient production plans. ; These two alternative models for measuring efficiency are employed to study the efficiency of highest level bank holding companies in the United States in 1994. The contractural interest rates these banks obtain on their loans and other assets are shown to influence their expected profit, profit risk, market value, and efficiency.Banks and banking - Costs

    Evidence on the Objectives of Bank Managers

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    The paper attempts to present empirical evidence on the behavior of bank managers - are they risk neutral and act on behalf of shareholders to maximize profits or risk averse and trade-off profits for risk reduction? The paper examines the bank's choice of financial capital since increasing financial capital reduces the risk of insolvency. A multiproduct cost function which incorporates asset quality and the risk faced by uninsured bank depositors is derived from a model of utility maximization. The authors' interpretation of the model is that it explicitly models a kind of x-efficiency. Because a bank may desire to trade-off risk and return, it may not use the cost minimizing level of financial capital. The authors extend the model of Hughes and Mester (1993) to allow a bank's choice of financial capital level to reflect its preference for return versus risk. The model consists of the cost function, share equations, and demand for financial capital equation, which are estimated jointly. The authors find evidence that banks in all size categories are acting in a non-risk neutral manner. Estimates of scale and scope economies based on this model show economies of scale at banks in all size categories. The authors also find evidence of product-specific scope econo-mies, cost complementarity between some outputs, and cost non-complementarity between other outputs.

    Learning to like or dislike : revealing similarities and differences between evaluative learning effects

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    Researchers study phenomena such as the mere-exposure effect, evaluative conditioning, and persuasion to learn more about the ways in which likes and dislikes can be formed and changed. Often, these phenomena are studied in isolation. Here, we review and integrate conceptual analyses that highlight ways to relate these different phenomena and that reveal new avenues for research on evaluative learning. At the core of these analyses lies the idea that evaluative learning can be defined as changes in liking that are due to regularities in the environment. We discuss how this definition allows one to distinguish different types of evaluative learning on the basis of the nature of regularities (e.g., in the presence of one stimulus vs. in the presence of two stimuli) and the function of regularities (i.e., symbolic vs. nonsymbolic)

    Evaluative conditioning as a symbolic phenomenon: on the relation between evaluative conditioning, evaluative conditioning via instructions, and persuasion

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    Evaluative conditioning (EC) is sometimes portrayed as a primitive way of changing attitudes that is fundamentally different from persuasion via arguments. We provide a new perspective on the nature of EC and its relation to persuasion by exploring the idea that stimulus pairings can function as a symbol that conveys the nature of the relation between stimuli. We put forward the concept of symbolic EC to refer to changes in liking that occur because stimulus pairings function as symbols. The idea of symbolic EC is consistent with at least some current theories of persuasion. It clarifies what EC research can add to the understanding of the origins of our preferences and has implications for how (symbolic and non-symbolic) EC can be established, the boundaries of EC research, and cognitive and functional models of EC

    The Emerging Wealth Belt: New Jersey's New Millenium Geography

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    Describes the emergence of an economic cluster of counties in New Jersey and explains the reason for this new spatial alignment of the economy. The report also traces the historical shifts in the economic geography of New Jersey from its rural beginnings to its high technology present. Finally, the report describes the countervailing deomgraphy and economic intiatives that once more may tilt growth back to urban New Jersey. It notes, however, that a variety of economic and public policy challenges raise serious questions about the outcome of the redirection of our state's spatial development

    A contextual behavioral approach to the study of (persecutory) delusions

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    Throughout the past century the topic of delusions has mainly been studied by researchers operating at the mental level of analysis. According to this perspective, delusional beliefs, as well as their emergence and persistence, stem from an interplay between (dysfunctional) mental representations and processes. Our paper aims to provide a starting point for researchers and clinicians interested in examining the topic of delusions from a functional-analytic perspective. We begin with a brief review of the research literature with a particular focus on persecutory delusions. Thereafter we introduce Contextual Behavioral Science (CBS), Relational Frame Theory (RFT) and a behavioral phenomenon known as arbitrarily applicable relational responding (AARR). Drawing upon AARR, and recent empirical developments within CBS, we argue that (persecutory) delusions may be conceptualized, studied and influenced using a functional-analytic approach. We consider future directions for research in this area as well as clinical interventions aimed at influencing delusions and their expression

    Efficiency in banking: theory, practice, and evidence

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    Great strides have been made in the theory of bank technology in terms of explaining banks’ comparative advantage in producing informationally intensive assets and financial services and in diversifying or offsetting a variety of risks. Great strides have also been made in explaining sub-par managerial performance in terms of agency theory and in applying these theories to analyze the particular environment of banking. In recent years, the empirical modeling of bank technology and the measurement of bank performance have begun to incorporate these theoretical developments and yield interesting insights that reflect the unique nature and role of banking in modern economies. This paper gives an overview of two general empirical approaches to measuring bank performance and discusses some of the applications of these approaches found in the literature.Banks and banking - Research
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