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151.
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153.
We investigate whether dividends convey information about the risk of a company by examining the reaction of implied volatility in the option market to the announcement of a dividend initiation. Implied volatility decreases after the announcement and the magnitude of the decline in volatility is positively related to both the magnitude of cumulative abnormal returns (CAR) in the equity markets and the size of the dividend. Additionally, firms with weaker (stronger) corporate governance experience larger (smaller) declines in implied volatility. Cross sectional analysis shows that a one-standard deviation decline in measures of risk increases the 2-day CAR by 74–137 basis points. Our results suggest that dividend initiations signal declining firm risk.  相似文献   
154.
We determine the optimal investment strategy to minimize the probability of an individual’s lifetime ruin when the underlying model parameters are subject to a shock. Specifically, we consider two possibilities: (1) changes in the individual’s net consumption and mortality rate and (2) changes in the parameters of the financial market. We assume that these rates might change once at a random time. Changes in an individual’s net consumption and mortality rate occur when the individual experiences an accident or other unexpected life event, while changes in the financial market occur due to shifts in the economy or in the political climate. We apply perturbation analysis to approximate the probability of lifetime ruin and the corresponding optimal investment strategy for small changes in the model parameters and observe numerically that these approximations are reasonable ones, even when the changes are not small.  相似文献   
155.
We consider the problem of efficiency and existence of a competitive equilibrium in exhaustible resource markets where extraction costs are nonconvex. Nonconvexity is shown to imply that (1) (efficient) extraction ceases to the left of the minimum efficient scale, i.e., where average costs exceed marginal costs; and (2) a competitive equilibrium does not exist. Introduction of a backstop technology (which induces a flat portion of the industry demand curve) restores both existence and efficiency, provided that the backstop price is sufficiently low. If firms face even a small amount of uncertainty regarding their rivals' stocks, a backstop technology is sufficient to restore existence of competitive equilibrium, even if the backstop price is very high. In this case, however, the competitive equilibrium is not efficient.  相似文献   
156.
When an insurer wouldn't pay for a drug his patient needed, the author let loose a barrage of letters. See what made them work.  相似文献   
157.
We report a case of abdominal actinomycosis demonstrated on computed tomography (CT) as an isolated mesenteric mass with radiating linear and nodular densities. The lesion mimicked a mesenteric tumor with desmoplastic reaction. The clinical and radiological features of this uncommon entity are reviewed.  相似文献   
158.
An individual demand function is said to satisfy the finite basis property when its set of Engel curves has a finite spanning subset. In the present letter we discuss why this property underlies the theory of exact aggregation.  相似文献   
159.
Homeownership rates equal the number of households that own homes divided by the number of households in the population. Differences in the propensity to form a household, therefore, may contribute to changes in homeownership rates over time in addition to long-standing racial gaps in homeownership. We examine these issues on an age-specific basis using data from the 1970 to 2000 public use microsamples of the decennial census. Results indicate that lower headship rates tend to reduce homeownership rates. This pattern is most notable for individuals in their early and mid 20s. For these individuals, declining headship rates between 1970 and 2000 reduced homeownership rates by three to five percentage points. Moreover, 2000 African American headship rates narrow white–black gaps in homeownership by roughly three percentage points, whereas 2000 Hispanic headship rates widen white–Hispanic gaps in homeownership by two to three percentage points. Thus, controlling for differences in headship behavior, white–black homeownership gaps are somewhat more severe than previously recognized, but the reverse is true for white–Hispanic gaps.  相似文献   
160.
This paper introduces and tests Bid Function Equilibria (BFE) in the British spot market for electricity. BFE extend von der Fehr and Harbord's (1993) multi-unit auction model of wholesale electricity markets by allowing firms to have heterogeneous costs for different generating units. Pure-strategy equilibria in BFE predict asymmetric bidding by producers: a single firm (the “price-setter") bids strategically while other firms (“non-price-setters") bid their costs. We test for asymmetries in firms' bid functions in the British spot market between 1993 and 1995 and find strong empirical support for the theory. We conclude that BFE have important implications for the design and governance of electricity markets.  相似文献   
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