Debt management in a small open economy: A theoretical and an empirical study for Belgium

This article analyzes the effects of debt management and its consequence for the control of base money in a small open economy (Belgium). The study compares the effects obtained from a small theoretical model with the results of a larger empirical model.The theoretical model focuses on the financing of government by money operation, on the bond rate, and on the international reserve of the Central Bank.The empirical model is a medium-term one, including the demand and the supply sectors of the economy and permitting simultaneous analysis of real and financial variables.The effects of an endogeneous or exogenous debt management have been studied by numerical simulation of modification in the public expenditure, the world trade, and the discount rate.     

Factors influencing contraception continuation rates: The oral and the intrauterine methods

The technique of multi-sort analysis was used to compare the relative duration of use of oral and intrauterine contraception among low socio-economic groups in Baltimore City. The clinical records of over 12,000 women who had received contraception through the Baltimore public services were analyzed. The type of method a woman used was found to be the most important factor affecting her probability of continuing contraception. Her age, race, and how long she had been using the method also influenced this probability. The strictness of the criteria used for the definition of continuation rates and the fact that experience was incomplete for many intrauterine contraceptors probably in part explain the somewhat low continuation rates obtained for both methods. It is suggested that the intrinsic characteristics of each method may lead to a clinical impression favoring the oral even when statistical evidence, as presented here, favors the intrauterine method.     

No sustained effect of aerobic or resistance training on insulin sensitivity in nonobese, healthy older women

It is unclear whether long-term aerobic (AT) or resistance (RT) training can improve insulin sensitivity (IS) beyond the residual effect of the last training bout in older women (54-78 years). Therefore, a group of nonobese, healthy older women underwent 6 months of AT (n = 8) or RT (n = 10), and the authors measured IS 4 days after the last training bouts using the hyperinsulinemic-euglycemic clamp technique. Women trained 3 days/week. AT consisted of 25- to 60-min sessions of walking/jogging at 60-95% of maximal heart rate. RT consisted of three sets of nine exercises repeated 10 times at 80% of 1 repetition maximum. AT decreased fat mass, whereas both AT and RT increased fat-free mass. Neither training program, however, improved absolute or relative rates of glucose disposal. The authors therefore concluded that nonobese, healthy older women should perform AT or RT on a daily basis in order to improve IS and maintain the improvement.     

Tree-structured subgroup analysis for censored survival data: Validation of computationally inexpensive model selection criteria

The performance of computationally inexpensive model selection criteria in the context of tree-structured subgroup analysis is investigated. It is shown through simulation that no single model selection criterion exhibits a uniformly superior performance over a wide range of scenarios. Therefore, a two-stage approach for model selection is proposed and shown to perform satisfactorily. Applied example of subgroup analysis is presented. Problems associated with tree-structured subgroup analysis are discussed and practical solutions are suggested.     

Alcohol abuse on a college campus: A needs assessment

This paper reports the results of a needs assessment study conducted by a university-based alcohol abuse prevention project. Data are presented on the drinking patterns and drinking problems of a random sample of 462 students. Results suggest that students are experiencing numerous difficulties in the physical, educational, legal and psychosocial areas due to their use of alcoholic beverages. Implications for prevention and intervention programming are discussed and the need for planning programs from a data-based perspective rather than a rational and intuitive approach is stressed.     

On Order Statistics from Sine Distribution

We derive closed form expressions for the first two moments of order statistics from the sine distribution. For the higher moments, a recurrence relation is given. We also give a recurrence relation for the product moments. These relations will be useful for moment computations based on ordered data.     

Waiting time to exhaust lottery numbers

Questions related to lotteries are usually of interest to the public since people think there is a magic formula which will help them to win lottery draws. This note shows how to compute the expected waiting time to observe specific numbers in a sequence of lottery draws and show that surprising facts are expected to occur.     

Edgeworth Corrections for Realized Volatility

The quality of the asymptotic normality of realized volatility can be poor if sampling does not occur at very high frequencies. In this article we consider an alternative approximation to the finite sample distribution of realized volatility based on Edgeworth expansions. In particular, we show how confidence intervals for integrated volatility can be constructed using these Edgeworth expansions. The Monte Carlo study we conduct shows that the intervals based on the Edgeworth corrections have improved properties relatively to the conventional intervals based on the normal approximation. Contrary to the bootstrap, the Edgeworth approach is an analytical approach that is easily implemented, without requiring any resampling of one's data. A comparison between the bootstrap and the Edgeworth expansion shows that the bootstrap outperforms the Edgeworth corrected intervals. Thus, if we are willing to incur in the additional computational cost involved in computing bootstrap intervals, these are preferred over the Edgeworth intervals. Nevertheless, if we are not willing to incur in this additional cost, our results suggest that Edgeworth corrected intervals should replace the conventional intervals based on the first order normal approximation.