1,053 research outputs found

    Do Labor Markets Provide Enough Short Hour Jobs? An Analysis of Work Hours and Work Incentives

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    This paper examines the role that work incentives play in the determination of work hours. Following previous research by Lang (1989), we use a conventional efficiency wage model to analyze how firms respond to worker preferences regarding wage-hours packages. We find that when workers are homogeneous, the role of worker preferences in determining work hours is similar to the simple neoclassical model of labor supply. For instance, if worker preferences shift in favor of shorter hours, firms will respond by offering jobs entailing shorter hours. When workers have heterogeneous preferences, however, employers will want to use a worker's hours preferences as a signal for the responsiveness of the worker to the work incentives used by the firm, and workers in turn may not reveal their hours preferences. Our key finding in this instance is that the labor market equilibrium may be characterized by a sub-optimal number of short-hour jobs. This shortage of short-hour jobs is likely to be found in high wage labor markets.

    "When Knowledge is an Asset: Explaining the Organizational Structure of Large Law Firms"

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    We study the economics of employment relationships through theoretical and empirical analyses of an unusual set of firms, large law firms. Our point of departure is the "property rights" approach that emphasizes the centrality of ownership's legal rights to control important, nonhuman assets of the enterprise. From this perspective, large law firms are an interesting and potentially important object of study, because the most valuable assets of these firms take the form of knowledge--particularly knowledge of the needs and interests of clients. We argue that the two most distinctive organizational features of large law firms, the use of "up or out" promotion contests and the practice of having winners become residual claimants in the firm, emerge naturally in this setting. In addition to explaining otherwise anomalous features of the up-or-out partnership system, this paper suggests a general framework for analyzing organizations where assets reside in the brains of employees.

    A robust lesion boundary segmentation algorithm using level set methods

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    This paper addresses the issue of accurate lesion segmentation in retinal imagery, using level set methods and a novel stopping mechanism - an elementary features scheme. Specifically, the curve propagation is guided by a gradient map built using a combination of histogram equalization and robust statistics. The stopping mechanism uses elementary features gathered as the curve deforms over time, and then using a lesionness measure, defined herein, ’looks back in time’ to find the point at which the curve best fits the real object. We compare the proposed method against five other segmentation algorithms performed on 50 randomly selected images of exudates with a database of clinician demarcated boundaries as ground truth

    Using shape entropy as a feature to lesion boundary segmentation with level sets

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    Accurate lesion segmentation in retinal imagery is an area of vast research. Of the many segmentation methods available very few are insensitive to topological changes on noisy surfaces. This paper presents an extension to earlier work on a novel stopping mechanism for level sets. The elementary features scheme (ELS) in [5] is extended to include shape entropy as a feature used to ’look back in time’ and find the point at which the curve best fits the real object. We compare the proposed extension against the original algorithm for timing and accuracy using 50 randomly selected images of exudates with a database of clinician demarcated boundaries as ground truth. While this work is presented applied to medical imagery, it can be used for any application involving the segmentation of bright or dark blobs on noisy images

    Extrinsic Rewards and Intrinsic Motives: Standard and Behavioral Approaches to Agency and Labor Markets

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    Employers structure pay and employment relationships to mitigate agency problems. A large literature in economics documents how the resolution of these problems shapes personnel policies and labor markets. For the most part, the study of agency in employment relationships relies on highly stylized assumptions regarding human motivation, e.g., that employees seek to earn as much money as possible with minimal effort. In this essay, we explore the consequences of introducing behavioral complexity and realism into models of agency within organizations. Specifically, we assess the insights gained by allowing employees to be guided by such motivations as the desire to compare favorably to others, the aspiration to contribute to intrinsically worthwhile goals, and the inclination to reciprocate generosity or exact retribution for perceived wrongs. More provocatively, from the standpoint of standard economics, we also consider the possibility that people are driven, in ways that may be opaque even to themselves, by the desire to earn social esteem or to shape and reinforce identity.agency, motivation, employment relationships, behavioral economics

    When Knowledge is an Asset: Explaining the Organizational Structure of Large Law Firms

    Get PDF
    We study the economics of employment relationships through theoretical and empirical analysis of an unusual set of firms, large law firms. Our point of departure is the "property rights" approach that emphasizes the centrality of ownership's legal rights to control important, non-human assets of the enterprise. From this perspective, large law firms are an interesting and potentially important object of study because the most valuable assets of these firms take the form of knowledge - particularly knowledge of the needs and interests of clients. We argue that the two most distinctive organizational features of large law firms, the use of "up or out" promotion contests and the practice of having winners become residual claimants in the firm, emerge naturally in this setting. In addition to explaining otherwise anomalous features of the up-or-out partnership system, this paper suggests a general framework for analyzing organizations where assets reside in the brains of employees.

    Lesion boundary segmentation using level set methods

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    This paper addresses the issue of accurate lesion segmentation in retinal imagery, using level set methods and a novel stopping mechanism - an elementary features scheme. Specifically, the curve propagation is guided by a gradient map built using a combination of histogram equalization and robust statistics. The stopping mechanism uses elementary features gathered as the curve deforms over time, and then using a lesionness measure, defined herein, ’looks back in time’ to find the point at which the curve best fits the real object. We implement the level set using a fast upwind scheme and compare the proposed method against five other segmentation algorithms performed on 50 randomly selected images of exudates with a database of clinician marked-up boundaries as ground truth

    Feedlot Performance of Heifers as Affected by Spaying and Hormone Treatment

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    Thirty-three percent of the animals which comprised the fed slaughter market in 1966 were heifers (U.S.D.S., 1967). When heifers are compared to steers, the gain at a slower rate, require more feed under similar feeding systems and sell at a lower price. These are important economic considerations in view of the large number of heifers fed for slaughter. The meat from heifers has been shown to be equal to that of steers in eating quality. It, however, sells at a lower price because heifer carcasses tend to be fatter and to have more waste as fat trim than steer carcasses when fed to the same market grade. The margin of profit on which livestock feeders operate is usually small. Profits often depend on rapid and efficient live-weight gains because of frequent negative margins between buying and selling prices of the animals. The makes it necessary to analyze the rations and methods of feeding and to study ways in which they may be improved. One method available is hormone administration which many be in the form of an additive to the feed or an implant placed under the skin of the animal. The feed additive or implant furnishes no essential nutrients but are substances used in relatively small amounts to improve gain, feed efficiency or carcass quality. Relatively little research has been published on methods of fattening heifers for market. Since heifers make up a considerable portion of the fed cattle, more research is needed to study ways of improving feedlot performance and to determine the most profitable ways to feed them. This experiment was conducted to determine the effects of spaying and the effects of diethylstilbestrol and Synovex-H (200 mg. testosterone propionate and 20 mg. estradiol benzoate) implants on feedlot performance and certain carcass characteristics of spayed and nonspayed heifers

    Automated retinal analysis

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    Diabetes is a chronic disease affecting over 2% of the population in the UK [1]. Long-term complications of diabetes can affect many different systems of the body including the retina of the eye. In the retina, diabetes can lead to a disease called diabetic retinopathy, one of the leading causes of blindness in the working population of industrialised countries. The risk of visual loss from diabetic retinopathy can be reduced if treatment is given at the onset of sight-threatening retinopathy. To detect early indicators of the disease, the UK National Screening Committee have recommended that diabetic patients should receive annual screening by digital colour fundal photography [2]. Manually grading retinal images is a subjective and costly process requiring highly skilled staff. This thesis describes an automated diagnostic system based oil image processing and neural network techniques, which analyses digital fundus images so that early signs of sight threatening retinopathy can be identified. Within retinal analysis this research has concentrated on the development of four algorithms: optic nerve head segmentation, lesion segmentation, image quality assessment and vessel width measurements. This research amalgamated these four algorithms with two existing techniques to form an integrated diagnostic system. The diagnostic system when used as a 'pre-filtering' tool successfully reduced the number of images requiring human grading by 74.3%: this was achieved by identifying and excluding images without sight threatening maculopathy from manual screening
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