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181.
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Two measures of extremist political attitudes are used to test the relationship between social participation, social status, and extremist attitudes. The expected relationships are found only for a measure called “support for democratic institutions.” Another measure of political attitudes, vigilantism, was found not to relate to the independent variables. We conclude that people who may adhere to abstract democratic ideals, at the same time may not reject the use of extralegal force to further their political goals. The findings also suggest that the “mobilization function” of social participation will need to be further specified.  相似文献   
184.
E Van der Voort 《Omega》1982,10(5):507-523
This article describes the EC-EFOM 12C model in general and refers where possible to existing documentation. It also reports on the first completed experimental case study and on planned future analysis. This model was developed in one of the research programs undertaken by the European Commission aimed primarily at multinational studies. Data are obtained from research carried out by an interactive network of national implementation teams working with a central group at the Commission. The energy system used is an oriented network carrying the primary energy over intermediate stages till finally meeting consumers' demand. The numerical information, constituting the attributes that characterise the various energy transformation processes, is stored in the European energy data base. About 225 transformation processes distributed over 17 subsystems characterised for six time periods up till 2020 for all EC countries are involved. The management of the data base is performed by an interactive software and this data base is designed for use in simulation studies and for linear programming optimisation with various objective functions. The model has been used in a parallel case study to explore substitution possibilities between an investment policy reducing the primary energy imports and one where these investments are restrained at the cost of having to import more primary energy. Results are shown and briefly discussed. Finally the relationship of this EFOM 12C model with the other EC models developed in the same research subprogram is outlined.  相似文献   
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The New York City Administration for Children's Services (ACS) instituted a neighborhood-based services system through the realignment of all foster care, preventive, and protective services along community district lines. ACS, with its community partners, also formed neighborhood-based networks to improve service coordination and collaboration among key community stakeholders and to shape a multisystem strategy tailored to each district informed by child welfare data. Based on analysis of neighborhood-specific census tract child welfare data, ACS initiated the Community Partnership to Strengthen Families project to address the disproportionate number of foster care placements originating from a small group of high-need communities, including Manhattan's Central Harlem. This article describes examples of specific strategies based on the Central Harlem experience.  相似文献   
187.
Vision communication is considered to be essential for leaders to mobilize followers, but knowledge of how and why vision communication may influence followers is scarce. We argue that visions may invite followers to create an ideal self (a desired image of the self). Subsequent consideration of this ideal self may motivate followers to make the ideal self (and thus the vision) reality. Furthermore, we propose that visions that focus on followers (by addressing followers personally and involving them in the vision) are more likely to lead to the creation of an ideal self and hence to higher follower performance than visions that do not focus on followers. Moreover, we argue that this effect is particularly strong for followers with a promotion self-regulatory focus, a focus on reaching ideals and ideal selves, because promotion focus causes sensitivity to the presence or absence of ideals (Higgins, 1987, 1996, 1997). The results of two experiments support our predictions.  相似文献   
188.
The Fisher exact test has been unjustly dismissed by some as ‘only conditional,’ whereas it is unconditionally the uniform most powerful test among all unbiased tests, tests of size α and with power greater than its nominal level of significance α. The problem with this truly optimal test is that it requires randomization at the critical value(s) to be of size α. Obviously, in practice, one does not want to conclude that ‘with probability x the we have a statistical significant result.’ Usually, the hypothesis is rejected only if the test statistic's outcome is more extreme than the critical value, reducing the actual size considerably.

The randomized unconditional Fisher exact is constructed (using Neyman–structure arguments) by deriving a conditional randomized test randomizing at critical values c(t) by probabilities γ(t), that both depend on the total number of successes T (the complete-sufficient statistic for the nuisance parameter—the common success probability) conditioned upon.

In this paper, the Fisher exact is approximated by deriving nonrandomized conditional tests with critical region including the critical value only if γ (t) > γ0, for a fixed threshold value γ0, such that the size of the unconditional modified test is for all value of the nuisance parameter—the common success probability—smaller, but as close as possible to α. It will be seen that this greatly improves the size of the test as compared with the conservative nonrandomized Fisher exact test.

Size, power, and p value comparison with the (virtual) randomized Fisher exact test, and the conservative nonrandomized Fisher exact, Pearson's chi-square test, with the more competitive mid-p value, the McDonald's modification, and Boschloo's modifications are performed under the assumption of two binomial samples.  相似文献   
189.
Probability plots are often used to estimate the parameters of distributions. Using large sample properties of the empirical distribution function and order statistics, weights to stabilize the variance in order to perform weighted least squares regression are derived. Weighted least squares regression is then applied to the estimation of the parameters of the Weibull, and the Gumbel distribution. The weights are independent of the parameters of the distributions considered. Monte Carlo simulation shows that the weighted least-squares estimators outperform the usual least-squares estimators totally, especially in small samples.  相似文献   
190.
We introduce a class of random fields that can be understood as discrete versions of multicolour polygonal fields built on regular linear tessellations. We focus first on a subclass of consistent polygonal fields, for which we show Markovianity and solvability by means of a dynamic representation. This representation is used to design new sampling techniques for Gibbsian modifications of such fields, a class which covers lattice‐based random fields. A flux‐based modification is applied to the extraction of the field tracks network from a Synthetic Aperture Radar image of a rural area.  相似文献   
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