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41.
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Autocorrelations are found in the disturbance terms of regressions employed by L. R. Klein and R. F. Kosobud in a global model of growth employing five celebrated ratios of economics. This paper summarizes the Klein-Kosobud conclusions, modifies them by removing the autocorrelations, and extends the model to include more recent years. The modified conclusions hold even with the added observations.  相似文献   
43.
A heteroscedastic regression based on the odd log-logistic Marshall–Olkin normal (OLLMON) distribution is defined by extending previous models. Some structural properties of this distribution are presented. The estimation of the parameters is addressed by maximum likelihood. For different parameter settings, sample sizes and some scenarios, various simulations investigate the performance of the heteroscedastic OLLMON regression. We use residual analysis to detect influential observations and to check the model assumptions. The new regression explains the mass loss of different wood species in civil construction in Brazil.  相似文献   
44.
Two-year chronic bioassays were conducted by using B6C3F1 female mice fed several concentrations of two different mixtures of coal tars from manufactured gas waste sites or benzo(a)pyrene (BaP). The purpose of the study was to obtain estimates of cancer potency of coal tar mixtures, by using conventional regulatory methods, for use in manufactured gas waste site remediation. A secondary purpose was to investigate the validity of using the concentration of a single potent carcinogen, in this case benzo(a)pyrene, to estimate the relative risk for a coal tar mixture. The study has shown that BaP dominates the cancer risk when its concentration is greater than 6,300 ppm in the coal tar mixture. In this case the most sensitive tissue site is the forestomach. Using low-dose linear extrapolation, the lifetime cancer risk for humans is estimated to be: Risk < 1.03 x 10(-4) (ppm coal tar in total diet) + 240 x 10(-4) (ppm BaP in total diet), based on forestomach tumors. If the BaP concentration in the coal tar mixture is less than 6,300 ppm, the more likely case, then lung tumors provide the largest estimated upper limit of risk, Risk < 2.55 x 10(-4) (ppm coal tar in total diet), with no contribution of BaP to lung tumors. The upper limit of the cancer potency (slope factor) for lifetime oral exposure to benzo(a)pyrene is 1.2 x 10(-3) per microgram per kg body weight per day from this Good Laboratory Practice (GLP) study compared with the current value of 7.3 x 10(-3) per microgram per kg body weight per day listed in the U.S. EPA Integrated Risk Information System.  相似文献   
45.
今天,日益增长的全球资本主义经济是一张复杂的动态的网络,这个网络由社会、文化以及反映我们个人和大众的意识的经济体制构成。随着意识创造并联结了所有事物这一观点被人们日渐认可,以及全球责任感的增强,资本主义经济体制可以切实地被改变,从而促进经济的长期繁荣。  相似文献   
46.
Pulier (2000, Theory and Decision 49: 291) and Machina (2000, Theory and Decision 49: 293) seek to dissolve the Barrett–Arntzenius infinite decision puzzle (1999, Theory and Decision 46: 101). The proposed dissolutions, however, are based on misunderstandings concerning how the puzzle works and the nature of supertasks more generally. We will describe the puzzle in a simplified form, address the recent misunderstandings, and describe possible morals for decision theory.  相似文献   
47.
In late 2009 China launched an innovative, voluntary programme that by 2011 had extended pension coverage to 326.4 million people in the rural sector, including contributors and beneficiaries. It requires one contribution per year and provides a flat‐rate benefit and a contributions‐related benefit through a contributory individual account, with a government guarantee that the benefit will continue for life. The programme encourages participation of persons who do not pay income taxes, and thus have no tax incentive to participate, by providing substantial government subsidies. As a further incentive, old‐age benefits are provided to older parents when all their adult children participate in the contributory programme.  相似文献   
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In this paper we seek to explain the activity presidential position taking on roll call votes in the House. Position taking may help presidents pursue their policy agendas, but time and available resources constrain their ability to take positions. Even though position taking is a discretionary presidential action, it occurs in the legislative arena and, thus, presidents must consider elements in both institutions as well as outside conditions when making this decision. Accordingly, we posit a multiple perspectives approach to explain the number of presidential positions on votes in the House. Our multivariate two-stage least squares regression reveals that variables from all three environments (executive, legislative and exogenous) within our multiple perspectives approach are necessary to adequately explain presidential position taking overall and when divided according to domestic and foreign policy positions.  相似文献   
50.
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