1,126 research outputs found
Taste, Information, and Asset Prices: Implications for the Valuation of CSR
Firms often undertake activities that do not necessarily increase cash flows (e.g., costly investments in corporate social responsibility or CSR), and some investors value these non cash activities (i.e., they have a “taste” for these activities). We develop a model to capture this phenomenon and focus on the asset-pricing implications of differences in investors’ tastes for firms’ activities and outputs. Our model shows that, first, investor taste differences provide a basis for investor clientele effects that are endogenously determined by the shares demanded by different types of investors. Second, because the market must clear at one price, investors’ demands are influenced by all dimensions of firm output even if their preferences are only over some dimensions. Third, information releases cause trading volume, even when all investors have the same information. Fourth, investor taste provides a rationale for corporate spin-offs that help firms better target their shareholder bases. Finally, individual social responsibility can lead to corporate social responsibility when managers care about stock price because price reacts to investments in CSR activities
Lobbying and Uniform Disclosure Regulation
This study examines the costs and benefits of uniform accounting regulation in the presence of heterogeneous firms that can lobby the regulator. A commitment to uniform regulation reduces economic distortions caused by lobbying by creating a free-rider problem between lobbying firms at the cost of forcing the same treatment on heterogeneous firms. Resolving this tradeoff, an institutional commitment to uniformity is socially desirable when firms are sufficiently homogeneous or the costs of lobbying to society are large. We show that the regulatory intensity for a given firm can be increasing or decreasing in the degree of uniformity, even though uniformity always reduces lobbying. Our analysis sheds light on the determinants of standard-setting institutions and their effects on corporate governance and lobbying efforts
Interstitial chemotherapy with biodegradable BCNU (Gliadel®) wafers in the treatment of malignant gliomas
Malignant gliomas represent the majority of primary brain tumors, and the prognosis of the patients afflicted with these tumors has been historically dismal, with almost uniform progressive neurologic impairment and rapid death. Even with multimodal treatment using surgery, focal radiation, and chemotherapy, no major strides were made until recently. The development of interstitial BCNU wafers (carmustine wafers, Gliadel®) has led to promising results in the treatment of a selected patients with malignant gliomas, as well as with other intracranial malignancies.BCNU is one of the first systemic chemotherapies which had obtained United States Food and Drug Administration (FDA) approval for the treatment of brain tumors. However, systemic use has been hampered by the modest prolongation of survival and by the prolonged myelosuppression and potentially fatal pulmonary toxicity. The development of interstitial therapies with BCNU represented a great step forward, allowing direct delivery to the tumor bed, with virtually no systemic toxicities. Clinical studies of BCNU wafers have showed good efficacy in both newly diagnosed and recurrent gliomas, as well as a possible therapeutic role in other primary or secondary intracranial malignancies. New studies are currently underway trying to improve the efficacy of the BCNU wafers (Gliadel®) by combining them with different systemic chemotherapies. An overview of the current knowledge ranging from the preclinical developments, to the efficacy and safety seen in the clinical trials and in clinical practice following the drug approval to the future avenues of research is therefore timely
Biometric Performance as a Function of Gallery Size
Many developers of biometric systems start with modest samples before general
deployment. They are interested in how their systems will work with much larger
samples. We evaluated the effect of gallery size on biometric performance.
Identification rates describe the performance of biometric identification,
whereas ROC-based measures describe the performance of biometric authentication
(verification). Therefore, we examined how increases in gallery size affected
identification rates (i.e., Rank-1 Identification Rate, or Rank-1 IR) and
ROC-based measures such as equal error rate (EER). We studied these phenomena
with synthetic data as well as real data from a face recognition study. It is
well known that the Rank-1 IR declines with increasing gallery size. We have
provided further insight into this decline. We have shown that this
relationship is linear in log(Gallery Size). We have also shown that this
decline can be counteracted with the inclusion of additional information
(features) for larger gallery sizes. We have also described the curves which
can be used to predict how much additional information is required to stabilize
the Rank-1 IR as a function of gallery size. These equations are also linear in
log(gallery size). We have also shown that the entire ROC curve is not
systematically affected by gallery size, and so ROC-based scalar performance
metrics such as EER are also stable across gallery size.Comment: 19 pages, 9 Figures, 0 Table
Global Stability of a Premixed Reaction Zone (Time-Dependent Liñan’s Problem)
Global stability properties of a premixed, three-dimensional reaction zone are considered. In the nonadiabatic case (i.e., when there is a heat exchange between the reaction zone and the burned gases) there is a unique, spatially one-dimensional steady state that is shown to be unstable (respectively, asymptotically stable) if the reaction zone is cooled (respectively, heated) by the burned mixture. In the adiabatic case, there is a unique (up to spatial translations) steady state that is shown to be stable. In addition, the large-time asymptotic behavior of the solution is analyzed to obtain sufficient conditions on the initial data for stabilization. Previous partial numerical results on linear stability of one-dimensional reaction zones are thereby confirmed and extended
Comparative Genomic Hybridization Analysis of Astrocytomas: Prognostic and Diagnostic Implications.
Astrocytoma is comprised of a group of common intracranial neoplasms that are classified into four grades based on the World Health Organization histological criteria and patient survival. To date, histological grade, patient age, and clinical performance, as reflected in the Karnofsky score, are the most reliable prognostic predictors. Recently, there has been a significant effort to identify additional prognostic markers using objective molecular genetic techniques. We believe that the identification of such markers will characterize new chromosomal loci important in astrocytoma progression and aid clinical diagnosis and prognosis. To this end, our laboratory used comparative genomic hybridization to identify DNA sequence copy number changes in 102 astrocytomas. Novel losses of 19p loci were detected in low-grade pilocytic astrocytomas and losses of loci on 9p, 10, and 22 along with gains on 7, 19, and 20 were detected in a significant proportion of high-grade astrocytomas. The Cox proportional hazards statistical modeling showed that the presence of +7q and -10q comparative genomic hybridization alterations significantly increased a patient\u27s risk of dying, independent of histological grade. This investigation demonstrates the efficacy of comparative genomic hybridization for identifying tumor suppressor and oncogene loci in different astrocytic grades. The cumulative effect of these loci is an important consideration in their diagnostic and prognostic implications
The topology of U-duality (sub-)groups
We discuss the topology of the symmetry groups appearing in compactified
(super-)gravity, and discuss two applications. First, we demonstrate that for 3
dimensional sigma models on a symmetric space G/H with G non-compact and H the
maximal compact subgroup of G, the possibility of oxidation to a higher
dimensional theory can immediately be deduced from the topology of H. Second,
by comparing the actual symmetry groups appearing in maximal supergravities
with the subgroups of SL(32,R) and Spin(32), we argue that these groups cannot
serve as a local symmetry group for M-theory in a formulation of de Wit-Nicolai
type.Comment: 18 pages, LaTeX, 1 figure, 2 table
Clustering Properties of restframe UV selected galaxies II: Migration of Star Formation sites with cosmic time from GALEX and CFHTLS
We analyze the clustering properties of ultraviolet selected galaxies by
using GALEX-SDSS data at z<0.6 and CFHTLS deep u' imaging at z=1. These
datasets provide a unique basis at z< 1 which can be directly compared with
high redshift samples built with similar selection criteria. We discuss the
dependence of the correlation function parameters (r0, delta) on the
ultraviolet luminosity as well as the linear bias evolution. We find that the
bias parameter shows a gradual decline from high (b > 2) to low redshift (b ~
0.79^{+0.1}_{-0.08}). When accounting for the fraction of the star formation
activity enclosed in the different samples, our results suggest that the bulk
of star formation migrated from high mass dark matter halos at z>2 (10^12 <
M_min < 10^13 M_sun, located in high density regions), to less massive halos at
low redshift (M_min < 10^12 M_sun, located in low density regions). This result
extends the ``downsizing'' picture (shift of the star formation activity from
high stellar mass systems at high z to low stellar mass at low z) to the dark
matter distribution.Comment: Accepted for Publication in the Special GALEX Ap. J. Supplement,
December 2007 Version with full resolution fig1 available at
http://taltos.pha.jhu.edu/~sebastien/papers/Galex_p2.ps.g
Evidence and Ideology in Macroeconomics: The Case of Investment Cycles
The paper reports the principal findings of a long term research project on the description and explanation of business cycles. The research strongly confirmed the older view that business cycles have large systematic components that take the form of investment cycles. These quasi-periodic movements can be represented as low order, stochastic, dynamic processes with complex eigenvalues. Specifically, there is a fixed investment cycle of about 8 years and an inventory cycle of about 4 years. Maximum entropy spectral analysis was employed for the description of the cycles and continuous time econometrics for the explanatory models. The central explanatory mechanism is the second order accelerator, which incorporates adjustment costs both in relation to the capital stock and the rate of investment. By means of parametric resonance it was possible to show, both theoretically and empirically how cycles aggregate from the micro to the macro level. The same mathematical tool was also used to explain the international convergence of cycles. I argue that the theory of investment cycles was abandoned for ideological, not for evidential reasons. Methodological issues are also discussed
- …