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941.
Laban A. J. Ogallo 《Journal of applied statistics》1986,13(1):49-56
ARIMA (p, d, q) models were fitted to areal annual rainfall of two homogeneous regions in East Africa with rainfall records extending between the period 1922–80. The areal estimates of the regional rainfall were derived from the time series of the first eigenvector, which was significantly dominant at each of the two regions. The first eigenvector accounted for about 80% of the total rainfall variance in each region.
The class of ARIMA (p, d, q) models which best fitted the areal indices of relative wetness/dryness were the A R M A (3, 1) models. Tests of forecasting skill however indicated low skill in the forecasts given by these models. In all cases the models accounted for less than 50% of the total variance.
Spectral analysis of the indices time series indicated dominant quasi-periodic fluctuations around 2.2–2.8 years, 3–3.7 years, 5–6 years and 10–13 years. These spectral bands however accounted for very low proportion of the total rainfall variance. 相似文献
942.
Dinkel R 《Allgemeines Statistisches Archiv》1986,70(1):28-51
This paper focuses on theories and techniques for forecasting fertility and mortality. Period and cohort analyses of fertility and mortality in Germany over the past century are first discussed. Alternative techniques for forecasting future trends in these variables in the Federal Republic of Germany are then outlined. The economic and social policy consequences of different mortality and fertility assumptions are also briefly noted. 相似文献
943.
A fact-gathering, experimental game proved to be an effective instrument in the needs assessment phase of an adolescent sexuality educational program aimed at low-income females. The game ("Family Few"), which covered the topics of menstruation and reproduction, was played by 35 Black, Hispanic, and white females aged 13-16 years recruited from medical and psychiatric clinics in Miami, Florida. The goals of the game were to elicit terminology used by participants, identify and correct misconceptions and misinformation, and determine if learning could occur. Although 57% of participants reported prior exposure to formal sex education, misinformation about the need for activity curtailment during menstruation and the importance of early pregnancy detection was widespread. Group members believed they needed to restrict activities involving physical exercise, sexual relations, water, and cold during menses and were not likely to seek medical or family consultation regarding a missed period until the end of the 1st trimester of pregnancy. Also evident was a need for accurate information on the side effects, risk factors, benefits, and effectiveness of contraceptive methods. The group responses enabled the sex educators to prepare a culturally responsive, developmentally oriented curriculum for further work with disadvantaged female adolescents. The group process was ranked highly on the Likert Scale by these teenagers as an enjoyable, useful means of information dissemination and problem solving. 相似文献
944.
The authors describe a project, begun in 1981, to locate, list, and annotate all the published work based substantially on the census enumerators' books for nineteenth-century censuses for England and Wales. The results are currently available in a computerized file, enabling a variety of searches by topic, geographical area, and type of population. Information is provided on using the data and the computerized bibliography. The authors note that, subsequently, data for censuses of Scotland and Ireland have been added. 相似文献
945.
Shah NM 《The International migration review》1986,20(4):815-832
An analysis of the foreign population in Kuwait shows that foreign nationals make up 60 percent of the population and 78 percent of the labor force in Kuwait. The implications of these figures for the Kuwaiti labor force are discussed by analyzing the occupational structures of Kuwaitis and non-Kuwaitis. "Structural analysis of the labor force indicates that 62 percent of Kuwaiti males are concentrated in administrative and service occupations while their percentage in sales and production work has declined during 1970-80. This demonstrates the need for reorienting educational/training programs and changing Kuwaiti attitudes towards manual work to ensure the realization of the 'Kuwaitization' process, and balance the nationals with foreign nationals." mortality has stabilized at relatively high levels and there is resistance to family planning. The author concludes that the main cause of the stalling of the demographic transition process is to be found in the role of the state and the dynamics of the social structure and that "demographic trends will depend more on the changes in social structure, land reforms, and response of the formal governing system to the needs of the underprivileged sections of the society, rather than on the health and family planning policies." 相似文献
946.
The authors construct a theoretical framework for analyzing factors influencing international refugee movements. "On the basis of detailed case studies by the authors of the principal refugee flows generated in Asia, Africa, and Latin America from approximately 1960 to the present, it was found that international factors often intrude both directly and indirectly on the major types of social conflict that trigger refugee flows, and tend to exacerbate their effects. Refugees are also produced by conflicts that are manifestly international, but which are themselves often related to internal social conflict among the antagonists." 相似文献
947.
Weeks JR 《Teaching Sociology》1986,14(2):92-101
"I describe a course on international demography in this paper. The course enables students to use demographic concepts to understand the demographics of various countries and regions. The course involves an introduction, examination of specific geographic regions, and a concluding overview. I also describe several student projects and review available course materials." 相似文献
948.
According to recent evidence, adoptive placements that do not work out are increasingly common. This article reviews research on rates of, and contributors to, adoption and "foster-adoption" disruptions and dissolutions. Implications for practice are included. 相似文献
949.
Computers have become commonplace in nearly every setting, from home to office. In addition to their usefulness for managerial tasks, they have the potential to aid the primary decision-making tasks of professional social service workers. The benefits and background of such "expert systems" are explored, and the structure of one experimental consulting program for child welfare workers, PLACECON, is presented. 相似文献
950.
Two questions concerning the location of a single facility by a voting process are investigated for transportation networks: - What is the maximum number of customers located on the network preferring some rival point over a voting solution? - How does the average distance of the customers to the facility increase when a voting location instead of a Weber location is chosen for the facility? Complete answers are given for general networks and for certain planar networks, viz., the so-called generalized cacti. 相似文献