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101.
Kjell Hausken 《Risk analysis》2011,31(10):1632-1645
The article considers the optimal resource distribution in a parallel system between increasing protection and providing redundancy in a situation when the attacker's and defender's resources are stockpiling and the resource increment rate is constant. It is assumed that the system must perform within an exogenously given time horizon and the attack time probability is uniformly distributed along this horizon. The defender optimizes the resource distribution in order to minimize the system destruction probability during the time horizon. First, we find the optimal pace of construction of the new redundant elements assuming that the construction must start in the initial stage of the stockpiling process. We show that starting construction of new elements in the beginning of the system's existence results in its high initial vulnerability. Introducing the time delay before starting the construction can reduce the initial system vulnerability and the entire system destruction probability. The problem of optimization of time delay and new element construction pace is considered with and without constraint on the initial system vulnerability. Examples illustrating the methodology of the optimal defense strategy analysis are presented.  相似文献   
102.
We propose different multivariate nonparametric tests for factorial designs and derive their asymptotic distribution for the situation where the number of replications is limited, whereas the number of treatments goes to infinity (large a, small n case). The tests are based on separate rankings for the different variables, and they are therefore invariant under separate monotone transformations of the individual variables.  相似文献   
103.
The problem of constructing simultaneous confidence intervals for various measures of association is considered. Alternative bootstrap algorithms are given for approximating the sampling distributions of the quantities generating the confidence sets. The small sample performance of the procedures is illustrated using simulated data from 3- and 6-variate normal populations. The results are applied to a large multidimensional longitudinal data set from a study of the relationship between drug use and several behavioral attributes.  相似文献   
104.
ABSTRACT

Problem: Early onset, prevalence, and predictors of substance use – tobacco, alcohol-drinking, alcohol-drunkenness, and drugs – were studied in 13 and 14-year-old boys and girls in Sweden. Methods: Self-reported data in four communities were used (n = 1,716). A large set of psychological and social factors were tried as predictors of early onset use (n = 1,459). Results: There were few gender differences and low prevalence. Primary predictor for early onset in tobacco use was availability; perceived parental approval for alcohol use, and delinquent behaviors for alcohol-drunkenness and drug use. Conclusions: Individual behavioral factors and parental norms seem to be most important in this age.  相似文献   
105.
In this paper, we analyze determinants of marital dissolution, focusing on the alleged influences from public transfers, child allowance, and child support awards. We use a Norwegian panel of 2,806 couples with information on public and private transfers in cases of divorce. The sample was observed over a 5-year period, with the purpose of registering marital dissolution. We find that the level of transfers has a significantly positive effect on divorce probability and that the distribution of transfers in favor of the wife increases this probability. Our findings are consistent with noncooperative family models allowing for inefficient outcomes.
Kjell Vaage (Corresponding author)Email:
  相似文献   
106.
Previous research using attendance‐based proxies for sentiment bias in sports betting markets confirmed the presence of investor sentiment in these markets. We use data from social media (Facebook “Likes”) to proxy for sentiment bias and analyze variation in bookmakers' prices investor sentiment. Based on betting data from seven professional sports leagues in Europe and North America, we find evidence that bookmakers increase prices for bets on teams with relatively more Facebook “Likes,” indicating the presence of price‐insensitive investors with sentiment bias. These price changes do not affect informational efficiency in this market. (JEL L81, G14)  相似文献   
107.
The double journey (work and study) may result or aggravate health problems, including sleep disturbances, as observed in previous studies with high school students. The aim of this study is to analyze the sleep-wake cycle and perceived sleepiness of working college students during weekdays. Twenty-three healthy college male students, 21-24 years old, working during the day and attending classes in the evening, participated in this study. During five consecutive days, the students filled out daily activities logs and wore actigraphs. Mean sleeping time was lower than 6 hours per night. No significant differences were observed in the sleep-wake cycle during the weekdays. The observed lack of changes in the sleepwake cycle of these college students might occur as participants were not on a free schedule, but exposed to social constraints, as was the regular attendance to evening college and day work activities. Sleepiness worsened over the evening school hours. Those results show the burden carried by College students who perform double activities - work and study.  相似文献   
108.
The purpose of this paper was to compare children placed out-of-home because of parental substance abuse (PSA) with children placed for other reasons (NPSA), and to explore the association between PSA and mental health problems in a Norwegian sample of 6- to 12-year-old children in out-of-home care (N = 109). Several group differences were found related to the children themselves, their families and the Child Welfare case. The PSA children had less total difficulties, conduct problems and emotional problems than the NPSA children assessed by the teachers on the Revised Rutter Scale. However, both groups had far more mental health problems than children in general. The most important variable explaining the group difference in all subgroups of mental health problems was the extent of prosocial behavior in the children, but being placed for behavioral problems also explained a significant part of total difficulties and conduct problems. Variables like gender, discipline problems and socioeconomic conditions did not have a significant effect. The conclusion of the study was that prosocial behavior might be regarded as an important protective factor against mental health problems, which is an argument for investing in programs focusing on enhancing the placed children's mastering strategies.  相似文献   
109.
Norwegian registry data are used to investigate the location decisions of a full population cohort of young adults as they complete their education, establish separate households, and form their own families. We find that the labor market opportunities and family ties of both partners affect these location choices. Surprisingly, married men live significantly closer to their own parents than do married women, even if they have children, and this difference cannot be explained by differences in observed characteristics. The principal source of excess female distance from parents in this population is the relatively low mobility of men without a college degree, particularly in rural areas. Despite evidence that intergenerational resource flows, such as childcare and eldercare, are particularly important between women and their parents, the family connections of husbands appear to dominate the location decisions of less-educated married couples.  相似文献   
110.
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