9,808 research outputs found
Bishop-Phelps-Bolloba's theorem on bounded closed convex sets
This paper deals with the \emph{Bishop-Phelps-Bollob\'as property}
(\emph{BPBp} for short) on bounded closed convex subsets of a Banach space ,
not just on its closed unit ball . We firstly prove that the \emph{BPBp}
holds for bounded linear functionals on arbitrary bounded closed convex subsets
of a real Banach space. We show that for all finite dimensional Banach spaces
and the pair has the \emph{BPBp} on every bounded closed convex
subset of , and also that for a Banach space with property
the pair has the \emph{BPBp} on every bounded closed absolutely convex
subset of an arbitrary Banach space . For a bounded closed absorbing
convex subset of with positive modulus convexity we get that the pair
has the \emph{BPBp} on for every Banach space . We further
obtain that for an Asplund space and for a locally compact Hausdorff ,
the pair has the \emph{BPBp} on every bounded closed absolutely
convex subset of . Finally we study the stability of the \emph{BPBp} on
a bounded closed convex set for the -sum or -sum of a
family of Banach spaces
First detection of 22 GHz H2O masers in TX Camelopardalis
Simultaneous time monitoring observations of HO , SiO
= 1--0, 2--1, 3--2, and SiO = 0, = 1--0 lines were carried
out in the direction of the Mira variable star TX Cam with the Korean VLBI
Network single dish radio telescopes. For the first time, the HO maser
emission from TX Cam was detected near the stellar velocity at five epochs from
April 10, 2013 ( = 3.13) to June 4, 2014 ( = 3.89) including
minimum optical phases. The intensities of HO masers are very weak
compared to SiO masers. The variation of peak antenna temperature ratios among
SiO = 1, = 1--0, = 2--1, and = 3--2 masers is investigated
according to their phases. The shift of peak velocities of HO and SiO
masers with respect to the stellar velocity is also investigated according to
observed optical phases. The HO maser emission occurs around the stellar
velocity during our monitoring interval. On the other hand, the peak velocities
of SiO masers show a spread compared to the stellar velocity. The peak
velocities of SiO = 2--1, and = 3--2 masers show a smaller spread with
respect to the stellar velocity than those of SiO = 1--0 masers. These
simultaneous observations of multi-frequencies will provide a good constraint
for maser pumping models and a good probe for investigating the stellar
atmosphere and envelope according to their different excitation conditions.Comment: 10 page
Does Managerial Risk-Taking Incentive for R&D Investments Translate to Future Earnings?
The convex pay-off structure of executive stock options (ESO) incentivizes CEOs to increase their firm stock-return volatility, thereby increasing their wealth in option portfolio. In this paper, I address two research questions. I first test if this managerial incentive induces executives to take on more risky projects in R&D that increases stock- return volatility, hence, boosting their personal wealth. I derive vega to measure managerial incentive, and vega is a dollar change in ESO for a 0.01 change in stock- return volatility. I find that there is a positive and statistically significant relationship between vega and R&D investment, which suggests that managers whose wealth is closely tied to stock options are more incentivized to invest in risky R&D projects to increase their wealth and stock-return volatility. This result is statistically significant and robust after adjusting for inflation and controlling for firm and industry-fixed effects. With this finding, I proceed to test if managerial risk-taking incentive for R&D investments translate to future earnings. Lev and Sougiannis (1996) establish that future earnings is a function of both tangible and intangible assets, and R&D increases with firm’s subsequent earnings. Since R&D spending changes with managerial incentive, I test if the interactive variable of vega and R&D has a positive effect on firm’s future earnings. I find that managerial incentive for undertaking R&D investments has a positive and statistically significant association with future earnings under industry-fixed effects specifications. When controlling for firm-fixed effects, the result yielded similar results to that of industry-fixed effects, but with less statistical significance. Lastly, for robustness check, I run the regression with a balanced panel data of tenured-CEOs, who stay with the firm for five years. I find that the result is positive and statistically significant for industry-fixed effects. However, for firm-fixed effects, I only find statistical significance at year t+k (k=3). This suggests that the realization of R&D investment to future earnings is not prevalent throughout all years when R&D decisions are made by incentivized, long-standing CEOs
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