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51.
An analysis of simple counting methods for ordering incomplete ordinal data   总被引:1,自引:0,他引:1  
Measurement in the social sciences often involves an attempt to completely order a set of entities on the basis of an underlying attribute. However, limitations of the measurement process often prevent complete empirical determination of the desired ordering. Nevertheless, the ordinal data obtained from the measurement process can be used in attempting to recover or construct more of the underlying order than is provided by the data. Previous research (Fishburn and Gehrlein, 1974a) has shown that a simple one-stage construction method, referred to as the cardinal rule, is fairly effective in correctly identifying ordered pairs in the underlying linear order that are not identified by the measurement process. The present paper re-examines the cardinal rule from the perspective of construction methods based on simple counting measures derived from the data, and argues that it is the best one-stage method in this class when a natural monotonicity assumption holds for the measurement process. The paper then examines two-stage construction rules that are based on the cardinal rule and the simple counting measures. It is shown that one of the two-stage rules gives better overall results than does the cardinal rule by itself.  相似文献   
52.
"The study compares determinants of internal and international migration intentions, drawing upon interview data from a sample of adults in Ilocos Norte, a largely rural province in the Philippines. A regression model is applied to test the relative determinants of intentions to migrate to Manila and to Hawaii. The study is based on a value-expectancy model of migration decision making. The results document the importance of subjective expectations related to the attainment of different values and goals in Manila and Hawaii."  相似文献   
53.
The results of a fertility survey carried out in the USSR in 1978 are presented. The survey included 33,076 women aged 18 to 59. Data are included on fertility rates by region and Union Republic and by urban or rural area, and on expected fertility of women aged 18 to 44. Changes in actual and desired fertility over time are compared for five-year periods from 1945 to 1978. Differences in fertility are analyzed by type of settlement, educational status, and nationality.  相似文献   
54.
A discussion of the 1980 U.S. census is presented. The authors suggest that the taking of a national census is not just a statistical exercise, but an exercise involving ethics, epistemology, law, and politics. They contend that conducting a national census can be defined as an ill-structured problem in which the various complexities imposed by multidisciplinarity cannot be separated. "The 1980 census is discussed as an ill-structured problem, and a method for treating such problems is presented, within which statistical information is only one component."  相似文献   
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Increasing attention is being given to the possible consequences which might follow from the exhaustion of the world's natural resources. Countering the pessimistic conclusions of such institutions as the Club of Rome, economists such as Wilfred Beckerman have emphasized the importance of substitution, pointing to many examples where a shortage of one raw material has led to the discovery or development of alternative materials, e.g. artificial for natural rubber, aluminium for copper.Substitution usually occurs through normal market mechanisms, i.e. changes in relative prices. However in some circumstances the market mechanism may be inhibited by a variety of factors, so that its operation requires to be supplemented by an outside agency. This article explores this possibility in relation to the paper making industry, which provides a particularly interesting example owing to the existence of a well established market in waste paper, the main substitute for the major natural resource, woodpulp.A brief indication is given of the relative importance of waste paper and an outline of the structure of the U.K. market; the conditions under which greater utilization of waste paper might occur are then considered taking a sideways look at the influence of the individual. In the final section the various implications for the role of the state are summarized.  相似文献   
57.
Beyond coping     
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Wavelet thresholding of spectra has to be handled with care when the spectra are the predictors of a regression problem. Indeed, a blind thresholding of the signal followed by a regression method often leads to deteriorated predictions. The scope of this article is to show that sparse regression methods, applied in the wavelet domain, perform an automatic thresholding: the most relevant wavelet coefficients are selected to optimize the prediction of a given target of interest. This approach can be seen as a joint thresholding designed for a predictive purpose. The method is illustrated on a real world problem where metabolomic data are linked to poison ingestion. This example proves the usefulness of wavelet expansion and the good behavior of sparse and regularized methods. A comparison study is performed between the two-steps approach (wavelet thresholding and regression) and the one-step approach (selection of wavelet coefficients with a sparse regression). The comparison includes two types of wavelet bases, various thresholding methods, and various regression methods and is evaluated by calculating prediction performances. Information about the location of the most important features on the spectra was also obtained and used to identify the most relevant metabolites involved in the mice poisoning.  相似文献   
60.
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