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91.
Using a spectral approach, the authors propose tests to detect multivariate ARCH effects in the residuals from a multivariate regression model. The tests are based on a comparison, via a quadratic norm, between the uniform density and a kernel‐based spectral density estimator of the squared residuals and cross products of residuals. The proposed tests are consistent under an arbitrary fixed alternative. The authors present a new application of the test due to Hosking (1980) which is seen to be a special case of their approach involving the truncated uniform kernel. However, they typically obtain more powerful procedures when using a different weighting. The authors consider especially the procedure of Robinson (1991) for choosing the smoothing parameter of the spectral density estimator. They also introduce a generalized version of the test for ARCH effects due to Ling & Li (1997). They investigate the finite‐sample performance of their tests and compare them to existing tests including those of Ling & Li (1997) and the residual‐based diagnostics of Tse (2002).Finally, they present a financial application.  相似文献   
92.
Vallerand and his colleagues (Vallerand & Blanchard, 1999; Vallerand, Blanchard, Koestner, & Gagné, 2001) have recently proposed a new concept of passion. According to these authors, passion refers to a strong inclination toward an activity that we like, find important, and in which we invest time. Vallerand et al. have identified two types of passion: obsessive and harmonious. Obsessive passion refers to an internal pressure that forces an individual to engage in the activity. Harmonious passion, on the other hand, refers to an internal force that leads an individual to choose freely to engage in an activity. While obsessive passion has been shown in some circumstances to lead to negative psychological and physical consequences, harmonious passion generally leads to positive psychological and physical consequences. The purpose of the present research was to validate a measure of passion toward gambling: the Gambling Passion Scale (GPS). The GPS consists of two subscales (obsessive passion and harmonious passion) comprising five items each. Results from two studies involving a total of 340 participants revealed satisfactory internal consistency and temporal stability indices, as well as a two-factor structure supported by exploratory and confirmatory factor analyses. Finally, a series of partial correlational analyses between the two subscales and scales assessing behavioral measures related to gambling supported the construct validity of the GPS. The present results suggest that the GPS is a useful scale for research on gambling.  相似文献   
93.
This study identifies determinants of adolescents’ propensity to use outpatient mental care as well as factors predicting number of visits after contact with a provider was made. We examined three types of treatment outlets: day treatment program (DTP), mental health clinic (MHC), and private specialty services (PSS). Among youth, 1.6% visited DTP, 2.3% visited MHC, and 11.1% had PSS, with overlaps in services utilization. Results from multivariable logistic regressions indicate that most of the individual characteristics differentiated youth on odds of using MHC and PSS, but not DTP. Health status, alcohol dependence, drug dependence, and problematic conduct behaviors and having Medicaid increased the odds of using all three services. Censored regressions used to model number of visits among service users found that girls consistently used more visits than boys. The results suggest that policies that encourage seeking help to a mental care provider may be in instances different from those aimed at motivating retention in treatment.  相似文献   
94.
Physiological daily inhalation rates reported in our previous study for normal‐weight subjects 2.6–96 years old were compared to inhalation data determined in free‐living overweight/obese individuals (n = 661) aged 5–96 years. Inhalation rates were also calculated in normal‐weight (n = 408), overweight (n = 225), and obese classes 1, 2, and 3 adults (n = 134) aged 20–96 years. These inhalation values were based on published indirect calorimetry measurements (n = 1,069) and disappearance rates of oral doses of water isotopes (i.e., 2H2O and H218O) monitored by gas isotope ratio mass spectrometry usually in urine samples for an aggregate period of over 16,000 days. Ventilatory equivalents for overweight/obese subjects at rest and during their aggregate daytime activities (28.99 ± 6.03 L to 34.82 ± 8.22 L of air inhaled/L of oxygen consumed; mean ±  SD) were determined and used for calculations of inhalation rates. The interindividual variability factor calculated as the ratio of the highest 99th percentile to the lowest 1st percentile of daily inhalation rates is higher for absolute data expressed in m3/day (26.7) compared to those of data in m3/kg‐day (12.2) and m3/m2‐day (5.9). Higher absolute rates generally found in overweight/obese individuals compared to their normal‐weight counterparts suggest higher intakes of air pollutants (in μg/day) for the former compared to the latter during identical exposure concentrations and conditions. Highest absolute mean (24.57 m3/day) and 99th percentile (55.55 m3/day) values were found in obese class 2 adults. They inhale on average 8.21 m3 more air per day than normal‐weight adults.  相似文献   
95.
Parenthood postponement is a key demographic trend of the last three decades. In order to rationalize that stylized fact, we extend the canonical model by Barro and Becker (Econometrica 57:481–501, 1989) to include two—instead of one—reproduction periods. We examine how the cost structure of early and late children in terms of time and goods affects the optimal fertility timing. Then, we identify conditions that guarantee the existence and uniqueness of a stationary equilibrium with a stationary cohort size. Finally, we examine how the model can rationalize the observed postponement of births, and we highlight two plausible causes: (1) a general rise in the cost of children in terms of goods and (2) a decline in the degree of family altruism.  相似文献   
96.
This paper studies the optimal level of discretion in policymaking. We consider a fiscal policy model where the government has time‐inconsistent preferences with a present bias toward public spending. The government chooses a fiscal rule to trade off its desire to commit to not overspend against its desire to have flexibility to react to privately observed shocks to the value of spending. We analyze the optimal fiscal rule when the shocks are persistent. Unlike under independent and identically distributed shocks, we show that the ex ante optimal rule is not sequentially optimal, as it provides dynamic incentives. The ex ante optimal rule exhibits history dependence, with high shocks leading to an erosion of future fiscal discipline compared to low shocks, which lead to the reinstatement of discipline. The implied policy distortions oscillate over time given a sequence of high shocks, and can force the government to accumulate maximal debt and become immiserated in the long run.  相似文献   
97.
98.
We provide an overview of how the emerging field of social cognitive neuroscience can be linked to leadership theory and practice. A number of challenges are addressed, including theory development, as well as technical, measurement and methodological issues. In addition, we review recent leadership research that involves neuroscience applications, as well as areas that are closely related to leadership, such as emotional regulation and ethical reasoning and decision-making. Consideration is also given to how neuroscience might inform leadership development processes. We conclude with a discussion of the institutional challenges in conducting leadership research that incorporates neuroscience, and we consider potential limitations of such applications.  相似文献   
99.
This article deals with a Bayesian predictive approach for two-stage sequential analyses in clinical trials, applied to both frequentist and Bayesian tests. We propose to make a predictive inference based on the notion of satisfaction index and the data accrued so far together with future data. The computations and the simulation results concern an inferential problem, related to the binomial model.  相似文献   
100.
Political influences on short-term interest rates in seventeen OECD countries from 1960–1990 are measured. After controlling for unexpected changes in inflation and unemployment, as well as changes in the world interest rate, short-term interest rates in most countries do not respond to political events, neither the timing of elections nor changes in the governing party. Thus, on this criterion, the central banks in this sample do not reveal large differences in their degree of independence from political influence. The small differences are not closely related to rankings of central bank independence based on quantification of central bank laws.  相似文献   
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