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31.
The benefits of programme review, forward planning and control have been demonstrated at the university-wide level. Within a faculty or department, there is also a clear need for developing and using planning methods which are rationally based and forward looking if appropriate responses to changing social and academic trends are to be made. This paper delineates a number of planning and control variables encountered at the faculty or departmental level, describes the development and use of a computer-based interactive forecasting model, and discusses the advantages and limitations of such models in planning a faculty's progress toward its goals.  相似文献   
32.
Summary.  We present a new class of methods for high dimensional non-parametric regression and classification called sparse additive models. Our methods combine ideas from sparse linear modelling and additive non-parametric regression. We derive an algorithm for fitting the models that is practical and effective even when the number of covariates is larger than the sample size. Sparse additive models are essentially a functional version of the grouped lasso of Yuan and Lin. They are also closely related to the COSSO model of Lin and Zhang but decouple smoothing and sparsity, enabling the use of arbitrary non-parametric smoothers. We give an analysis of the theoretical properties of sparse additive models and present empirical results on synthetic and real data, showing that they can be effective in fitting sparse non-parametric models in high dimensional data.  相似文献   
33.
There are theories on brain functionality that can only be tested in very large models. In this work, a simulation model appropriate for working with large number of neurons was developed, and Information Theory measuring tools were designed to monitor the flow of information in such large networks. The model’s simulator can handle up to one million neurons in its current implementation by using a discretized version of the Lapicque integrate and fire neuron instead of interacting differential equations. A modular structure facilitates the setting of parameters of the neurons, networks, time and most importantly, architectural changes. Applications of this research are demonstrated by testing architectures in terms of mutual information. We present some preliminary architectural results showing that adding a virtual analogue to white matter called “jumps” to a simple representation of cortex results in: (1) an increase in the rate of mutual information flow, corresponding to the “bias” or “priming” hypothesis; thereby giving a possible explanation of the high speed response to stimuli in complex networks. (2) An increase in the stability of response of the network; i.e. a system with “jumps” is a more reliable machine. This also has an effect on the potential speed of response.  相似文献   
34.
The National Survey of Family Growth (1982) is used to examine the extent to which racial differences in premarital birth rates can be explained by differences in parents' socioeconomic status, family structure, and residential characteristics. The findings document a large diversity in premarital births within both populations. Black women from high-risk backgrounds are three times more likely to have a premarital birth than black women from low-risk backgrounds. Racial differences in premarital births arise because (1) black women are more likely to come from high-risk backgrounds and (2) black women from low-risk backgrounds are more likely to have a premarital birth than white women with similar characteristics. There are similar rates of premarital births by race among persons from high-risk backgrounds.  相似文献   
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36.
The complexity of the relationship between gambling and crime make empirical establishment of a relationship between the two difficult. Focusing on one state, we examine the impact of Indian gaming on crime in New Mexico. Specific crime rates in New Mexico counties with tribal gaming are discussed. Comparisons of the rates of specific crimes are made between New Mexico counties with tribal gaming and those without.  相似文献   
37.
The predictor that minimizes mean-squared prediction error is used to derive a goodness-of-fit measure that offers an asymptotically valid model selection criterion for a wide variety of regression models. In particular, a new goodness-of-fit criterion (cr2) is proposed for censored or otherwise limited dependent variables. The new goodness-of-fit measure is then applied to the analysis of duration.  相似文献   
38.
Advance letters are being used increasingly to combat the declinein response rates, but their effectiveness depends partly ontheir being read. In the face of the post-9/11 anthrax mailingscare, the Office for Survey Research (OSR) converted to usingadvance postcards rather than advance letters. Subsequently,the OSR conducted an experiment to test the effectiveness ofsending letters, postcards, or nothing to directory-listed numbersselected in a large random digit dial (RDD) telephone survey.In terms of response rates, the results clearly indicate thatsending advance letters is more effective than sending postcards,which, in turn, is more effective than sending nothing. A detailedcost-effectiveness evaluation indicates that sending lettersactually saves money, despite the increased costs associatedwith the mailings, compared to sending postcards; sending postcardsis also more cost-effective than not sending anything.  相似文献   
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40.
Marital paradigms comprise the guiding images that serve as reference models for a couple's relationship. Such individualized images can be understood as variations on a small set of basic themes. An understanding of clients' marital paradigms can help foeus treatment on the most appropriategoals usingapproaches and techniques that are most effective for a particular couple. An unselected group of 103 couples seen in systems-oriented marital therapy were reviewed, to identify outcome and treatment issues as a function of marital paradigm. Based on outcome criteria that took marital paradigm into account, 92% of 38 cases where both partners identified with the same basic paradigm were judged to be treatment successes, while only 60% of the cases where the partners identified with different paradigms could be considered successful outcomes. Clinical approaches based on experience with marital therapy conducted within a paradigmatic framework are presented.  相似文献   
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