2,565 research outputs found
The Unanticipated Effects of Insider Trading Regulation
Using a sample of 2,827 firms from 21 countries we examine whether insider trading laws achieve the primary objective for which they are introduced – protecting uninformed investors from private information-based trading. We find that when control is concentrated in the hands of a large shareholder, insider trading regulation is less effective in reducing private information-based trading if investor protection is poor. We suggest that controlling shareholders who are banned from trading may resort to covert expropriation of firm resources, creating more information asymmetry and thereby encouraging private information trading by informed outsiders. Consistent with this, we find evidence that when the rights of controlling shareholders are high, insider trading restrictions are associated with greater earnings opacity.http://deepblue.lib.umich.edu/bitstream/2027.42/40081/3/wp695.pd
To steal or not to steal: Firm attributes, legal environment, and valuation
Newly released data on corporate governance and disclosure practices reveal wide within-country variation, with the variation increasing as legal environment gets less investor friendly. This paper examines why firms practice high-quality governance when law does not require it; firm attributes that are related to the quality of governance; how the attributes interact with legal environment; and the relation between firm valuation and corporate governance. A simple model, in which a controlling shareholder trades off private benefits of diversion against costs that vary across countries and time, identifies three relevant firm attributes: investment opportunities, external financing, and ownership structure. Using firm-level governance and transparency data on 859 firms in 27 countries, we find that firms with greater growth opportunities, greater needs for external financing, and more concentrated cash flow rights practice higher-quality governance and disclose more. Moreover, firms that score higher in governance and transparency rankings are valued higher in the stock market. Equally important, all these relations are stronger in countries that are less investor friendly, demonstrating that firms do adapt to poor legal environments to establish efficient governance practices.http://deepblue.lib.umich.edu/bitstream/2027.42/39939/3/wp554.pd
The Unanticipated Effects of Insider Trading Regulation
Using a sample of 2,827 firms from 21 countries we examine whether insider trading laws achieve the primary objective for which they are introduced – protecting uninformed investors from private information-based trading. We find that when control is concentrated in the hands of a large shareholder, insider trading regulation is less effective in reducing private information-based trading if investor protection is poor. We suggest that controlling shareholders who are banned from trading may resort to covert expropriation of firm resources, creating more information asymmetry and thereby encouraging private information trading by informed outsiders. Consistent with this, we find evidence that when the rights of controlling shareholders are high, insider trading restrictions are associated with greater earnings opacity.Insider Trading Regulation, Ownership, Private Information Trading, Earnings Opacity
Determination of rate constant, binding constant, and binding number by fluorescence measurements of Gd3N@C80(OH)20 in D2O
ABSTRACT     Today MRI imagining techniques are capable of discerning between abnormal and normal complex tissues by providing contrasting images of these tissues. One drawback of using MRI imagining is its low sensitivity.  However, this sensitivity can be greatly enhanced by introducing contrasting agents who can provide a new pathway for water molecules to significantly relax faster and hence generate the desired “contrast†between healthy and unhealthy tissues.  We report the first ever recorded fluorescence emission spectrum of Gd3N@C80(OH)20; where -(OH)20 is the average number of hydroxyl groups. Our emission data indicates that the H2O- Gd3N@C80(OH)20 interactions lead to fluorescence quenching via a static quenching mechanism. The binding constant, Kb, on the other hand, was found to be of the same magnitude as interactions between human serum albumin and small organic acid but quite different, several orders of magnitude smaller, than protein nanoparticle complexes. Interestingly, the binding number, n, was found to be approximately 0.5, which in cases like this, is rounded to a whole number of one. The data also indicated an extremely fast rate constant on the order of 1012 L mol-1 s-1 which is outside of the diffusion-control regime. These results are presented within this report
Sulfa-Penicillin Therapy in an Open Joint
July 2, 1947, a black Quarter Horse gelding, age 6 years, was presented at the Stange Memorial Clinic with a scar formation on the dorsal surface of the right rear metatarsus. The owner suspected a sequestrum or a foreign body in this region, but an X-ray of the area revealed a chronic ostitis of the third metatarsal bone. A considerable amount of scar tissue was present on the skin over this area. No lameness was observed and there was no history of a previous lameness. The owner was advised that any treatment would be likely to excite the condition. Being a roping and bulldogging horse, the blemish was not detrimental to the value of the animal. The patient was discharged the same day
Mapping a Continental Shelf and Slope in the 1990s: A Tale of Three Multibeams
Increasing societal pressures on the U.S. continental shelves adjacent to dense population centers have brought to light the lack of accurate base maps in these areas. Existing bathymetric maps and random sidescan sonar surveys are either not accurate enough or do not provide the coverage necessary to make policy decisions. Until the mid 1990s, it was not financially prudent nor technically efficient to map the shallow shelves. However, the availability of high-resolution multibeam mapping systems now allow efficient and accurate mapping of the continental margins. In 1996 the U.S. Geological Survey began a large-scale seafloor mapping campaign on the continental shelf and slope adjacent to Los Angeles, CA. The first survey used a Kongsberg Simrad EM1000 (95 kHz). The survey continued in 1998 by mapping the slope and proximal basins from Newport to Long Beach, CA, using a Kongsberg Simrad EM300 (30 kHz). The area was completed in May 1999 by mapping the entire shelf adjacent to Long Beach, CA using an EM3000D (a dual-headed 300-kHz system). The mapping used both INS from the vehicle motion sensor and DGPS to provide position accuracies of ~1 m. All the data were processed in the field in near realtime using software developed at the Univ. of New Brunswick. Because of the different systems used and the range of water depths, the spatial resolution of the processed data varies from \u3c0.5 m on the inner shelf to 8 m on the basin floors.
Perspective overviews of backscatter draped over bathymetry reveals a host of geological features unknown to exist in this area. These features include shallow, linear gullys, barchan dunes, small-scale bedforms in shallow troughs, major canyon system complexes, large- and smallscale mass movements, faults, and large areas of outcrop. The effects on sediment transport of man-made features, such as sewer outfall pipes and dredge-disposal fields, are clearly delineated on the new maps. The maps provide the fundamental base maps for studies as varied as those involving benthic habitats, marine disposal sites, sediment transport, and tectonic ma
Ariel - Volume 3 Number 2
Editors
Richard J. Bonanno
Robin A. Edwards
Associate Editors
Steven Ager
Stephen Flynn
Tom Williams
Lay-out Editor
Eugenia Miller
Contributing Editors
Paul Bialas
Milton Packer
Robert Breckenridge
Lynne Porter
Mark Pearlman
Terry Burt
Mike Leo
Editors Emeritus
Delvyn C. Case, Jr.
Paul M. Fernhof
Outlier Detection Using Nonconvex Penalized Regression
This paper studies the outlier detection problem from the point of view of
penalized regressions. Our regression model adds one mean shift parameter for
each of the data points. We then apply a regularization favoring a sparse
vector of mean shift parameters. The usual penalty yields a convex
criterion, but we find that it fails to deliver a robust estimator. The
penalty corresponds to soft thresholding. We introduce a thresholding (denoted
by ) based iterative procedure for outlier detection (-IPOD). A
version based on hard thresholding correctly identifies outliers on some hard
test problems. We find that -IPOD is much faster than iteratively
reweighted least squares for large data because each iteration costs at most
(and sometimes much less) avoiding an least squares estimate.
We describe the connection between -IPOD and -estimators. Our
proposed method has one tuning parameter with which to both identify outliers
and estimate regression coefficients. A data-dependent choice can be made based
on BIC. The tuned -IPOD shows outstanding performance in identifying
outliers in various situations in comparison to other existing approaches. This
methodology extends to high-dimensional modeling with , if both the
coefficient vector and the outlier pattern are sparse
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