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31.
32.
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   
33.
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   
34.
In the production planning and control of discrete-parts manufacture, aggregation of parts into families, on the basis of similarity, is carried out to ease both long-horizon planning and short-horizon scheduling. Additional advantages are related to those of group technology (GT), such as simplifying the flow of parts and tools and reducing both set-up and production costs. The problem of formally forming part families is presented and discussed. Previous work is reviewed and assessed. Two solution approaches, one based on a location model, the other on simulated annealing, are presented and compared along with test results. The location formulation, which results in an integer programming model solved by Lagrangian relaxation, proved capable of producing solutions of excellent quality, but only for relatively small problem instances. In contrast, simulated annealing, which is a general heuristic approach to combinatorial optimization, produced solutions of comparable quality and could handle realistically large problem instances. However, careful design of the simulated annealing algorithm is crucially important. An effective design is presented.  相似文献   
35.
In this article, we first propose the modified Hannan–Rissanen Method for estimating the parameters of autoregressive moving average (ARMA) process with symmetric stable noise and symmetric stable generalized autoregressive conditional heteroskedastic (GARCH) noise. Next, we propose the modified empirical characteristic function method for the estimation of GARCH parameters with symmetric stable noise. Further, we show the efficiency, accuracy and simplicity of our methods with Monte-Carlo simulation. Finally, we apply our proposed methods to model the financial data.  相似文献   
36.
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   
37.
This paper investigates how workers’ “economic struggle” determines the “democratic class struggle,” and extends socialist electoral constituency. This paper argues that political outcomes, namely, electoral behavior, may not be understood independently of the labor process, especially its most militant manifestation, strikes. Rather than follow the customary conceptual dichotomy between the sphere of production and the political sphere, it is suggested that both strike activity and electoral participation are compatible political strategies that, under specific historical circumstances, may jointly determine the fate of the Socialist party. The leading question is how did the wave of strikes in post World War I Italy affect the electoral power of the Italian Socialist party, in comparison with another mass party, the Popular Catholic Party. Hierarchical Linear Modeling (HLM) is employed to analyze census, strike, and electoral data. It is found that strike activity and electoral democracy increased the electoral power of the Socialist party, whereas they had little effect on the power of the Catholic party. It is suggested that this was due to the Catholic non-revolutionary program which was ambivalent about the political role of strikes. It is concluded that the socialists’ political success was determined by their dual political strategy in both spheres, electoral participation, and organizing strikes.  相似文献   
38.
The study examines the determinants of social expenditure in Sri Lanka for the period 1970–2010. The data are from a new data set assembled by the authors. The social spending data are collected from the Central Bank of Sri Lanka on education, health, and also on welfare spending. The study explains the determinants of social spending considering the demand‐side and the supply‐side driving forces and finds that inequality issues have been a major concern of social policy in Sri Lanka. Similarly, this study implies the influence of political behavior to satisfy voters as explained by the fiscal illusion theory. The globalization is not significant for social expenditure as commonly assumed in developed countries. Even the consequences of the self‐interested behavior of bureaucrats are not evident in the Sri Lankan welfare sector.  相似文献   
39.
Sex offenders and sex crimes provoke a great deal of anxiety in our society, and over the past decade, lawmakers have passed a variety of social policies designed to protect the public from sexual victimization. The purpose of this study was to examine public perceptions about sex offenders and community protection policies. Data were obtained from a sample of 193 residents in Melbourne, Florida. It was hypothesized that the public holds some inaccurate beliefs about sex offenders, and that there is strong public support for community protection policies. It was found that community members believe that sex offenders have very high recidivism rates, view sex offenders as a homogeneous group with regard to risk, and are skeptical about the benefits of sex offender treatment. The hypothesis that public perceptions contradict empirical research was supported. Community members were overwhelmingly in favor of public disclosure of information about registered sex offenders, although they did not express as much support for residence restrictions. Implications for public policy, and for the media's role in shaping public perceptions, are discussed.  相似文献   
40.
Traditional theories of welfare state development divide into two camps: societal accounts and institutional accounts. The aim of the present article is to amend and enrich the institutional approach to US social policy by reconsidering key aspects of the genesis of the American welfare state: 1) showing that concepts such as 'policy feedback' and 'path dependence' need to be extended to encompass the effect of private social policies; and 2) taking policy paradigms and agenda setting more seriously than is the norm in institutional scholarship. The empirical analysis is divided into two parts. The first part explores the activities of the American Association for Labor Legislation (AALL) in the decade beginning in 1910 and the genesis of Social Security in the 1930s, while the second part examines the effect of the private benefit developments on policy choices between 1935 and 1965.  相似文献   
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