2,008 research outputs found

    Fairness, Efficiency and Insider Trading: Deconstructing the Coin of the Realm in the Information Age

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    Whether and how the federal securities laws should restrict insider trading is one of the most hotly debated topics in the securities law literature. Paradoxically, both the theoretical analysis and the legal rules concerning insider trading remain extraordinarily vague and ill-formed. What is the special character of insider trading that leads to this apparently irresolvable puzzle? In this Article, I argue that there is, in fact, nothing special about insider trading that creates this dilemma, but rather there is something special about the nature of information itself. Accordingly, this theoretical dilemma is not limited to insider trading regulation, but rather pervades all areas of intellectual property law. In this Article, I situate insider trading regulation within the larger body of intellectual property law by discussing three potential allocations of the property right in valuable inside information. First, inside information could be treated as a public resource, meaning that a person in possession of inside information could not legally exploit that advantage for personal profit. Such a regime would forbid some or all insider trading by forcing the disclosure to the marketplace of inside information prior to trading. I argue that regulators should reject this alternative because, despite it\u27s proponents\u27 tendency to justify the rule in terms of fairness, this proposal is unlikely to foster fairness in any meaningful way. Alternatively, the property right in valuable inside information could belong to issuers, as the producers of such information. I argue that regulators should reject this alternative because, despite its proponents? tendency to frame their arguments in terms of promoting informational efficiency, a legal regime treating inside information as the property of the issuer is unlikely to further that goal. In fact, such proposals assume an affirmative answer to a question that is fiercely debated in other areas of intellectual property law: does creating a property right in information producers incentivize additional production to the extent necessary to offset the social costs of excluding others from use of the information? Finally, the property right in valuable inside information could reside with outsider traders (traders who possess inside information, but are neither insiders nor constructive insiders of the issuer). I argue that regulators should pursue this alternative because, although there is no need to encourage issuers to create valuable inside information, the need to encourage the dissemination of such information to the marketplace has been recognized for many years. Accordingly, I propose in this Article a system of federal securities regulation that would permit trading by corporate outsiders who did not receive their information in a tip from an insider or constructive insider. Such a system, I argue, provides the hope of filling in the gaps left by the current disclose or abstain system, by encouraging the reflection of material information in stock market price without disclosure of the actual inside information. At the same time, this proposal avoids the perverse incentives and negative impacts on market efficiency attendant in a system that permits insider trading by corporate employees

    A systematic review of the screening accuracy of the HIV Dementia Scale and International HIV Dementia Scale.

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    BACKGROUND: The HIV Dementia Scale (HDS) and International HIV Dementia Scale (IHDS) are brief tools that have been developed to screen for and aid diagnosis of HIV-associated dementia (HAD). They are increasingly being used in clinical practice for minor neurocognitive disorder (MND) as well as HAD, despite uncertainty about their accuracy. METHODS AND FINDINGS: A systematic review of the accuracy of the HDS and IHDS was conducted. Studies were assessed on Standards for Reporting Diagnostic Accuracy criteria. Pooled sensitivity, specificity, likelihood ratios (LR) and diagnostic odds ratios (DOR) were calculated for each scale as a test for HAD or MND. We retrieved 15 studies of the HDS, 10 of the IHDS, and 1 of both scales. Thirteen studies of the HDS were conducted in North America, and 7 of the IHDS studies were conducted in sub-Saharan Africa. Estimates of accuracy were highly heterogeneous between studies for the HDS but less so for the IHDS. Pooled DOR for the HDS was 7.52 (95% confidence interval 3.75-15.11), sensitivity and specificity for HAD were estimated at 68.1% and 77.9%, and sensitivity and specificity for MND were estimated at 42.0% and 91.2%. Pooled DOR for the IHDS was 3.49 (2.12-5.73), sensitivity and specificity for HAD were 74.3% and 54.7%, and sensitivity and specificity for MND were 64.3% and 66.0%. CONCLUSION: Both scales were low in accuracy. The literature is limited by the lack of a gold standard, and variation in estimates of accuracy is likely to be due to differences in reference standard. There is a lack of studies comparing both scales, and they have been studied in different populations, but the IHDS may be less specific than the HDS. These rapid tests are not recommended for diagnostic use, and further research is required to inform their use in asymptomatic screening

    How the Proxy Rules Discourage Constructive Engagement: Regulatory Barriers to Electing a Minority of Directors

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    During the 1980s, both sides of the hostile takeover controversy viewed proxy contests in terms that bordered on the mythical. Those made uneasy by the takeover phenomenon, especially management, held out proxy contests as an alternative, almost utopian mechanism through which a civilized debate about corporate strategy and structure could be held. As the Delaware Supreme Court put it, [if the stockholders are displeased with the actions of their elected representatives [in blocking a hostile takeover], the powers of corporate democracy are at their disposal to turn the board out.” In contrast, those who believed that takeovers were necessary to displace inefficient management or otherwise change corporate policy dismissed the proxy contest as entirely ineffective. They argued that the costs of collective action arising from dispersed share ownership reduced to allegory the prospect that the proxy process could provide a viable means to correct management failure. With the benefit of a little hindsight, both views have turned out to be wrong. Takeover proponents\u27 dismissal of the proxy process ignored the dramatic growth in the holdings of institutional investors, and the resulting reduction in the costs associated with collective voting action. Moreover, takeover proponents\u27 dismissal of the proxy process seemed to stem from a preference (in the case of financial economists, often a purely intellectual preference) for market-based, price-driven mechanisms over ones that created a meaningful, substantive debate over corporate policy. Indeed, financial scholars often appeared to view the institutional complexity and substantive, process-driven dynamics associated with proxy contests with unease. The inefficiency of proxy contests was often assumed rather than treated as a hypothesis subject to empirical test

    Argo salinity: bias and uncertainty evaluation

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    Argo salinity is a key set of in situ ocean measurements for many scientific applications. However, use of the raw, unadjusted salinity data should be done with caution as they may contain bias from various instrument problems, most significant being from sensor calibration drift in the conductivity cells. For example, inclusion of biased but unadjusted Argo salinity has been shown to lead to spurious results in the global sea level estimates. Argo delayed-mode salinity data are data that have been evaluated and, if needed, adjusted for sensor drift. These delayed-mode data represent an improvement over the raw data because of the reduced bias, the detailed quality control flags, and the provision of uncertainty estimates. Such improvement may help researchers in scientific applications that are sensitive to salinity errors. Both the raw data and the delayed-mode data can be accessed via https://doi.org/10.17882/42182 (Argo, 2022). In this paper, we first describe the Argo delayed-mode process. The bias in the raw salinity data is then analyzed by using the adjustments that have been applied in delayed mode. There was an increase in salty bias in the raw Argo data beginning around 2015 and peaking during 2017–2018. This salty bias is expected to decrease in the coming years as the underlying manufacturer problem has likely been resolved. The best ways to use Argo data to ensure that the instrument bias is filtered out are then described. Finally, a validation of the Argo delayed-mode salinity dataset is carried out to quantify residual errors and regional variations in uncertainty. These results reinforce the need for continual re-evaluation of this global dataset.</p

    An Argo mixed layer climatology and database

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    Author Posting. © American Geophysical Union, 2017. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 44 (2017): 5618–5626, doi:10.1002/2017GL073426.A global climatology and database of mixed layer properties are computed from nearly 1,250,000 Argo profiles. The climatology is calculated with both a hybrid algorithm for detecting the mixed layer depth (MLD) and a standard threshold method. The climatology provides accurate information about the depth, properties, extent, and seasonal patterns of global mixed layers. The individual profile results in the database can be used to construct time series of mixed layer properties in specific regions of interest. The climatology and database are available online at http://mixedlayer.ucsd.edu. The MLDs calculated by the hybrid algorithm are shallower and generally more accurate than those of the threshold method, particularly in regions of deep winter mixed layers; the new climatology differs the most from existing mixed layer climatologies in these regions. Examples are presented from the Labrador and Irminger Seas, the Southern Ocean, and the North Atlantic Ocean near the Gulf Stream. In these regions the threshold method tends to overestimate winter MLDs by approximately 10% compared to the algorithm.National Science Foundation (NSF) Grant Numbers: OCE-0327544, OCE-0960928, OCE-1459474; NOAA Grant Number: NA10OAR43101392017-12-1

    Maximum Confidence Quantum Measurements

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    We consider the problem of discriminating between states of a specified set with maximum confidence. For a set of linearly independent states unambiguous discrimination is possible if we allow for the possibility of an inconclusive result. For linearly dependent sets an analogous measurement is one which allows us to be as confident as possible that when a given state is identified on the basis of the measurement result, it is indeed the correct state.Comment: 4 pages, 2 figure

    Conceptualizing the impacts of dual practice on the retention of public sector specialists - evidence from South Africa

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    Abstract Background ‘Dual practice’, or multiple job holding, generally involves public sector-based health workers taking additional work in the private sector. This form of the practice is purported to help retain public health care workers in low and middle-income countries’ public sectors through additional wage incentives. There has been little conceptual or empirical development of the relationship between dual practice and retention. Methods This article helps begin to fill this gap, drawing on empirical evidence from a qualitative study focusing on South African specialists. Fifty-one repeat, in-depth interviews were carried out with 28 doctors (predominantly specialists) with more than one job, in one public and one private urban hospital. Results Findings suggest dual practice can impact both positively and negatively on specialists’ intention to stay in the public sector. This is through multiple conceptual channels including those previously identified in the literature such as dual practice acting as a ‘stepping stone’ to private practice by reducing migration costs. Dual practice can also lead specialists to re-evaluate how they compare public and private jobs, and to overworking which can expedite decisions on whether to stay in the public sector or leave. Numerous respondents undertook dual practice without official permission. Conclusions The idea that dual practice helps retain public specialists in South Africa may be overstated. Yet banning the practice may be ineffective, given many undertake it without permission in any case. Regulation should be better enforced to ensure dual practice is not abused. The conceptual framework developed in this article could form a basis for further qualitative and quantitative inquiry

    Performance Evaluation of a Kinesthetic-Tactual Display

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    Simulator studies demonstrated the feasibility of using kinesthetic-tactual (KT) displays for providing collective and cyclic command information, and suggested that KT displays may increase pilot workload capability. A dual-axis laboratory tracking task suggested that beyond reduction in visual scanning, there may be additional sensory or cognitive benefits to the use of multiple sensory modalities. Single-axis laboratory tracking tasks revealed performance with a quickened KT display to be equivalent to performance with a quickened visual display for a low frequency sum-of-sinewaves input. In contrast, an unquickened KT display was inferior to an unquickened visual display. Full scale simulator studies and/or inflight testing are recommended to determine the generality of these results
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