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101.
金融资产的收益率和波动率是金融资产投资和风险管理等应用中的重要决定因素。针对收益率的新息过程与波动率的新息过程之间可能存在相关性的实际情况,将已实现波动区分为连续波动和跳跃波动,对收益率、连续波动和跳跃波动联合建模并刻画各时间序列模型新息之间的相关性,给出联合模型的最大似然估计法,使用2005年4月8日至2011年5月23日沪深300指数5分钟高频数据进行实证。研究结果表明,收益率、连续波动和跳跃波动的新息之间存在统计显著的相关性,对各时间序列单独建模估计的传统方法存在本质缺陷,沪深300指数已实现波动的杠杆效应及周日效应主要来自连续波动分量。联合模型通过对新息之间相关关系的合理刻画,提高了参数估计的有效性。 相似文献
102.
本文采用面板的Granger因果检验,对1997-2008年间我国24个省市自治区风险投资与创新之间因果关系进行的实证研究结果表明,风险投资和专利授权均是一阶单整变量;且Kao检验、Johansen Fisher检验和Pedroni检验的协整检验结果也十分显著。这不仅说明了风险投资和专利授权变量间存在长期稳定的均衡关系,而且还验证了"风险投资先于创新"假说的成立。但却没有发现"创新先于风险投资"的显著证据。 相似文献
103.
Birgit Beinsen 《Review of Managerial Science》2016,10(4):801-829
This paper provides a signaling explanation for benefits of conservative accounting in a debt contracting setting. It develops a model in which firms want to finance more or less risky projects through debt, which is private information. Creditors price the risk on average riskiness, which implies a relatively high interest rate for low-risk firms. These firms can signal their low-risk type by implementing a conservative accounting system. The accounting signal is used in a debt covenant that stipulates early repayment in case of a bad signal. Thus, the low-risk firms benefit from a lower interest cost, but at the cost of higher risk of being forced to liquidate a profitable project. The analysis establishes conditions for separating and pooling equilibria and determines their individual and social welfare implications. It shows that conservative accounting by low-risk firms can even increase social welfare if it mitigates underinvestment. 相似文献
104.
Medical advances and the growth of the elderly population have focused interest on trends in the health of the elderly. Three theories have been advanced to describe these trends: compression of morbidity, expansion of morbidity, and dynamic equilibrium. We applied multistate life table methods to the Medicare Current Beneficiary Survey to estimate active and disabled life expectancy from 1992 to 2003, defining disability as having difficulty with instrumental activities of daily living or activities of daily living. We found increases in active life expectancy past age 65 and decreases in life expectancy with severe disability. These trends are consistent with elements of both the theory of compression of morbidity and the theory of dynamic equilibrium. 相似文献
105.
This article outlines a formal model-based approach for inferring interregional age-specific migration streams in settings where such data are incomplete, inadequate, or unavailable. The estimation approach relies heavily on log-linear models, using them to impose some of the regularities exhibited by past age and spatial structures or to combine and borrow information drawn from other sources. The approach is illustrated using data from the 1990 and 2000 U.S. and Mexico censuses. 相似文献
106.
This research note combines two national Taiwanese data sets to investigate the relationships among low birth weight (LBW) babies, their parents' educational levels, and their future academic outcomes. We find that LBW is negatively correlated with the probability of such children attending college at age 18; however, when both parents are college or high school graduates, such negative effects may be partially offset. We also show that discrimination against daughters occurs, but only for daughters who were LBW babies. Moreover high parental education can buffer the LBW shock only among moderately LBW children (as compared with very LBW children) and full-term LBW children (as compared with preterm LBW children). 相似文献
107.
Teachman J 《Demography》2007,44(2):389-404
I use data from the 1979 National Longitudinal Study of Youth to examine the relationship between military service and marital timing for white men and black men during the 1980s. I use information about active-duty and reserve-duty service as well as veteran status to implement strong controls for selectivity. I find that active-duty military service increases the probability of first marriage for both whites and blacks. In part, this relationship is due to positive selectivity into the military and, for whites, to greater income and economic stability. Above and beyond the effects of selectivity, income, and economic stability, the effect of active-duty military service is particularly strong for black men. 相似文献
108.
The demography of disability and the effects of immigrant history: Older Asians in the United States 总被引:1,自引:0,他引:1
Using data from the 2000 U.S. census, we compare the older Asian population with U.S.-born, non-Hispanic whites with respect to three indicators of disability. Insofar as any Asian "advantage" in health vis-a-vis whites exists among the population aged 65 and over, our evidence suggests that it occurs primarily among the U.S.-born segments of this population. We also investigate how differences in disability levels among Asian immigrant groups are influenced by country of birth and by the combined effects of duration of residence in the United States and life cycle stage at entry. These results highlight the diversity of the older Asian population with respect to the ways in which immigration and origin history are linked to disability outcomes. We conclude that in later life, immigrant status confers few disability advantages among the Asian population in the United States. 相似文献
109.
Martin E 《Demography》2007,44(2):427-440
This article draws on evidence from an exploratory survey of living situations to assess the validity of assumptions about residence and to offer methodological innovations to improve coverage of people with tenuous attachment to households. These innovations include more inclusive probes and questions used to compile the roster of household residents; a review of the places a person stayed the previous few months; and a Residential Attachment scale that measures strength of attachment to households. This scale shows that it takes more probing to list tenuously attached people than most surveys do, suggesting that tenuously attached people are likely to be omitted from the typical survey roster. The Residential Attachment scale is correlated with social and economic participation in households, suggesting that participation is fairly high even among those with tenuous or no residential attachment. 相似文献
110.
Nepomnyaschy L 《Demography》2007,44(1):93-112
I use three waves of panel data to examine the relationship between child support payments and fathers' contact with their nonmarital children. I disaggregate support into fathers' formal and informal payments and incorporate cross-lagged effects models to identify the direction of causality between payments and contact. After including the behavior from the prior wave (lagged term) and a rich set of family characteristics, I find a marginally significant effect of paying formally at Time 1 on the likelihood of contact at Time 2 but no effect of contact at Time 1 on formal payments at Time 2. In the first examination of the relationship between informal support and father-child contact, I find a strong, positive reciprocal relationship between the likelihood and frequency of father-child contact and the likelihood and amount of informal support, with slightly stronger and more consistent effects of contact on payments than of payments on contact. 相似文献