共查询到20条相似文献，搜索用时 46 毫秒
1.
EDWARD NISSAN 《Growth and change》1994,25(4):411-426
ABSTRACT The construction of a composite index is described to rank U.S. metropolitan areas for educational attainment. The suggested methodology departs from traditional rank sum methods in that this approach utilizes data resulting in a continuous scale, whereas in the rank sum method, no use is made of the actual values of the data, but merely their rankings. The proposed index circumvents several practical problems because the numbers generated are metric measures allowing the use of arithmetic and statistical operations. Data used are pupil/teacher ratio, an effort index, and academic options in higher education. Comparisons are made across areas by population size and by geographic region. 相似文献
2.
SHU‐HEN CHIANG 《Growth and change》2012,43(1):143-166
Over the past few years, a large number of studies have focused on whether population or employment is critical to the source of metropolitan growth. However, only few attempts have so far been made to additionally consider the suburbanization stage and pattern of commuting, which may both enable us to explore this “chicken–egg” issue a little further. The purpose of this paper is to compare dwelling‐based (housing) with job‐based (job) employment to evaluate the net commuting. The Taipei metropolitan area, for example, now lies at the initial suburbanization stage with only population decentralization and massive in‐commuting to the central city. The estimation results based on a co‐integration system reveal that the central‐city employment can be regarded as an engine of this metropolitan economy. Besides, we also find that dwelling‐based employment distorts the causality between population and employment, especially from the variance‐decomposition accounts. Therefore, the importance of commuting to investigating the evolution of metropolitan economy should not be overlooked. 相似文献
3.
旨在明确农村饮水安全评价指标的具体含义,并对现有的定量评价方法进行论述。农村饮水安全问题具有模糊性、动态性及广泛性等特征。综合评价区域农村饮水安全现状需将水量、水质、方便程度及保证率4项指标进一步细化和规范化,从而建立一套完整的、符合地方实际的评价指标体系。指标权重值的确定是农村饮水安全定量评价的重难点。权重确定方法可划分为主观赋权法、客观赋权法及主客观组合赋权法。主观赋权法和客观赋权法均存在农村饮水安全多指标综合评价中,具有各自的优势及局限性,实现主客观赋权方法的优化组合,是确定农村饮水安全评价指标权重值的主要研究方向之一。 相似文献
4.
The authors examine nine indicators of quality of life in the 277 U.S. Standard Metropolitan Statistical Areas (SMSAs) in terms of their impact on the decision to migrate. The factors considered were utilized in the 1985 publication "Places Rated Almanac" and include climate, housing, health care, crime, transportation, education, recreation, arts, and economics. "The purpose of this paper is both to analyze several alternative methods by which the nine 'Places Rated' indicators have been combined in previous studies, and to estimate a new system of weights for combining such indicators from a multivariate model of metropolitan out-migration." In this article, the authors examine out-migration of metropolitan households during the years 1975-1980. "Coefficient estimates from a multivariate model of out-migration form the basis for a ranking of metropolitan areas in the third section. Also included are comparisons among this and other studies of both the implicit weights employed against the 'Places Rated' scores...to derive both overall measures of urban life quality, and how such quality varies by city size." 相似文献
5.
为了给用户提供可信的信息服务,需要对网络信息进行可信度评估,而评价网站可信度的方法是网络信息可信度评估的基础和重要组成部分,旨在探索农业综合型和专业型网站可信度评估的方法。应用模糊综合评价法对提出的网站可信度评估指标体系中的重要指标数据进行了融合,再以涉及油菜信息的网站为试验对象,进行试验数据采集与分析,对43个包含油菜信息的综合型和专业型网站可信度进行了计算和综合排序。试验Ⅰ选取了网站PR值、反向链接数、Alexa排名、页面收录数等4个指标,试验Ⅱ选取了网站PR值、反向链接数、Alexa排名、页面收录数、专业性等5个指标,分别进行模糊综合评价。试验结果表明：从网站综合实力判断网站可信度,农博网、中国农业信息网、一亩田油菜网、中华人民共和国农业部、中国农业科学院网对评评价指标体系Ⅰ反应较好;整体上国家级网站可信度高于地方级网站;网站可信度与当地的信息化和农业水平有一定关系;专业型网站与综合型网站差距较大。从网站综合实力和专业需求两方面判断网站可信度,较好的有农博网、中国农业信息网、中华人民共和国农业部。试验Ⅰ的评测指标适合于综合型网站可信度量,试验Ⅱ的评测指标适合于专业型网站可信度量。该文提出的网站可信度评价模型可为其他网站可信度评估提供参考,其中的指标可根据实际情况来选取以及确定其权重。 相似文献
6.
PAUL J. KOZLOWSKI 《Growth and change》1987,18(3):62-73
ABSTRACT Indexes of leading indicators are used to forecast short-run changes in economic activity in many states and metropolitan areas. This article examines the forecasting performance of a sample of such regional indexes over several business cycles. Although these indexes vary across regions, the results show that they do provide forecasts of recessions and recoveries and also exhibit some potential for forecasting quantitative changes in regional employment. 相似文献
7.
农业固体废弃物肥料化技术模糊综合评价 总被引：3，自引：0，他引：3
为了对农业固体废弃物肥料化技术的效益和功能进行综合定量评价,通过对现有成熟且已工程化运用的肥料化技术进行分析和模糊评价,构建出了一套由“目标层—准则层—指标层”3个层次、27个单项评价指标构成的肥料化技术评价指标体系,应用层次分析法确定了各指标的权重,并在肥料化技术评价指标体系和评价方法研究的基础上,采用模糊综合评价方法对目前国内外常用的8种肥料化技术进行了评价。评价结果表明：条垛翻抛堆肥技术为华中地区典型的肥料化技术;槽式机械翻抛堆肥技术为东北地区典型的肥料化技术;静态通风堆肥技术为西南地区典型的肥料化技术。并以辽宁、北京2个典型肥料化项目对模型进行了验证,实际情况与结果相吻合,表明本文研究提出的评价指标体系和方法学具有适用性。 相似文献
8.
Breeding planning and variety valuation can be supported only if weighting factors for the economically relevant performance traits are available. In plant breeding they are necessary for the calculation of selection indices as well as for the comparison of varieties and for quantifying the monetary impact of breeding progress. In this article the economic weights for the most important performance traits of sugar beet are calculated from the farmer's, the sugar factory's, and the national economy's point of view. Based upon economic weights for beet yield, sugar content, potassium, sodium, and ammo nitrogen content, a total of 19 varieties was compared with regard to physical and economic performance. The investigation shows that “best” and “worst” varieties differ in gross margin per ha by 270.— to 330.— DM. Indications were given for possibilities and limitations of the application of economic weights in breeding planning. 相似文献
9.
The sustainability of agricultural systems is frequently evaluated with indicators, which are synthetic variables describing complex systems. Each indicator deals with one aspect of sustainability (e.g. nutrients, pesticides, energy), and therefore the result of a complete assessment usually includes several indicator values. These values are frequently presented separately, while an integrated evaluation could benefit from the calculation of a single sustainability index. The aim of this work was to integrate 15 economic and environmental indicator values into a global sustainability index (Sg) ranging from 0 to 1.To calculate the indicators, we used a large data set of cropping systems management for 131 fields cultivated with arable crops in northern Italy, obtained through periodic interviews with farmers over a 2-year period. The fields were chosen to represent the main cropping systems in the area (cereals and forages, on animal and cereal farms). The 15 indicators describe a large variety of sustainability aspects, i.e. the economic performance and the management of energy, nutrients, soil, and pesticides.The indicator values were first converted into a sustainability score (Si; 0–1) applying continuous non-linear sustainability functions that use thresholds defining what is sustainable, unsustainable, or intermediate. We obtained 15 values of Si per each field, which we aggregated into Sg using indicator-specific weights provided by different stakeholders. This procedure permits not only the single indicators evaluation, but also to combine indicators for an assessment of cropping systems at field level.Permanent meadows, due to good management of soil, pesticides and nutrients, obtained the highest Sg, even when different weights were used. Continuous rice obtained the lowest Sg (due to unsatisfactory soil management, low energy production, and high pest and weed pressure, which involved a large use of pesticides), while maize was intermediate, with good economic and energetic performance.The methodology allows a transparent, repeatable, sound, and quantitative evaluation of sustainability of agricultural systems. It can be easily expanded by adding other indicators, and can be tailored by changing the thresholds used to calculate Si and the weights assigned by stakeholder groups. 相似文献
10.
Natural Amenities and Rural Development: Understanding Spatial and Distributional Attributes 总被引：1，自引：0，他引：1
ABSTRACT Contemporary resource management practice and rural development planning increasingly emphasize the integration of resource extractive industries with non‐market‐based recreational and amenity values. There is a growing empirical literature which suggests that natural amenities impact regional economies through aggregate measures of economic performance such as population, income, and/or employment growth, and housing development. We maintain that assessing the developmental aspects of amenity‐led regional change requires a more thorough focus on alternative measures of economic performance such as income distribution and spatial organization. In the applied research presented here we investigate relationships between amenities and regional economic development indicators. Results suggest mixed and generally insignificant amenity‐based associations which highlight the need for appropriate regional economic modeling techniques that account for often dramatic spatial autocorrelation of natural amenity attributes. We conclude that with respect to amenity driven economic growth and development “place in space” matters. 相似文献
11.
ELDON D. SMITH 《Growth and change》1990,21(4):3-18
Approaches for analyzing employment stability with aggregated data for SICs in large regions or major metropolitan areas are misleading indicators of the impact of manufacturing growth in rural areas. Performance of moderate-sized individual establishments seriously impact total employment variation in small-employment-sized rural communities, requiring analysis of the determinants of employment stability of these establishments. Aggregate SIC performance and most conventional criteria for judging probable stability appear to provide very limited predictability for individual firm performance. However, manufacturing development appears generally to have desirable effects on community-wide employment stability. 相似文献
12.
GREGORY D. WOZNIAK 《Growth and change》1990,21(3):61-76
The purpose of this paper is to construct monthly manufacturing output indexes for a metropolitan area, employing a method used by the Federal Reserve Banks to construct regional manufacturing indexes. The Tulsa metropolitan area is the region considered. The index of total manufacturing output is included in a vector autoregression model of the Tulsa economy. The results indicate that the linkages between manufacturing activity and non-manufacturing employment differ from the linkages between employment in those sectors, and that since the early 1980s both sectors have become less sensitive to changes in the price of oil. 相似文献
13.
The British Government’s economic strategy for post‐Brexit Britain of achieving balanced regional growth by “driving growth across the whole country” echoes the objectives set by the Barlow Report of 1940. The regional policies that followed the Barlow Report were heavily influenced by papers written for the Commission by G D A (later Sir Donald) MacDougall. The first of these papers was included as an appendix to the report itself and introduced the shift‐share methodology to the analysis of regional employment growth, and subsequently shown to be flawed. The second paper considered the urban hierarchy and growth but was never fully developed. Consequently post‐war regional policy focussed on the contribution of industrial structure to employment growth without fully taking into account the urban hierarchy or regional locations of that employment. This article replaces the flawed shift‐share methodology with multifactor partitioning (MFP) and applies it to regional employment growth for the period 1971‐2012, a span of special interest because it largely coincides with British membership of the European Union (EU). The deficiencies in the second paper are addressed by introducing allometry to measure the employment growth of each region relative to that of Great Britain and then regression analysis to relate the allometries to distance from London. The results of the two sets of analyses highlight the need for a multiple‐factor, comprehensive, and integrated approach to regional policy and provide a benchmark against which to gauge the success of Britain's post‐Brexit policy of driving future growth across the whole country. 相似文献
14.
为了科学、准确地对农业气象服务效益进行评估和分析,结合威武市当地农业气象服务的特点,利用AHP（层次分析法）与BCG（波士顿矩阵）相结合的方法,将复杂的效益评估系统数学化、层次化、系统化,构建适合当地特色的新型农业气象服务效益评估模型,结合2015年武威市农业气象服务满意度调查问卷进行效益评估。结果表明,“气象部门对当地农业气象需求的了解程度与带来的社会和经济效益”、“预报要素准确率”、“气象服务产品特性”、“农业气象产品内容丰富性”等4类指标属于核心类项目,成为农气象服务中产生良好社会和经济效益的主要指标项目,“用户未来打算”属于发展型项目,具有良好的发展潜力。此次评估结果,能够使气象部门合理确定服务产品重点、改进服务内容,积极拓宽服务信息发布渠道,有效分配农业气象服务资源,对提高农业气象防灾减灾水平有着重要意义。 相似文献
15.
玉米不同时期抗旱性鉴定指标的灰色关联度与聚类分析 总被引：4，自引：0，他引：4
试验从玉米抗旱性的系统性和整体性出发,在玉米4个比较重要的生育时期,即:萌发期(播种-出苗)、苗期(出苗-拔节)、开花期(抽雄-吐丝)、灌浆期(授粉-收获)采用分阶段人工模拟干旱胁迫的方法,利用综合性状比较优良的超级玉米品种为试验材料,通过比较形态学、发育学、生理学等方面的抗旱性鉴定指标与玉米抗旱能力的关系,通过一些简便易测指标的分析筛选,建立一套可靠、迅速的指标体系。通过玉米抗旱性与各指标的相关分析、灰色关联度分析、聚类分析,明确了各指标与玉米抗旱性关系及抗旱性鉴定的指标体系,为综合评价不同玉米品种抗旱性奠定了基础。 相似文献
16.
ABSTRACT Targeting industry clusters for economic development has become popular despite the lack of empirical evidence about the spatial scales over which various clusters agglomerate. This paper identifies twenty manufacturing industry clusters from a principal components analysis of interindustry patterns of trade and measures the spatial employment concentration of each cluster's plants within a polycentric framework. Two to eight centers of employment concentration are detected within the Southern California region for each set of trade linkages. Our spatial half‐life measure reveals that half of a cluster's employment in associated establishments is located within a typical range of eight to twelve kilometers (about 5–7.5 miles) to the nearest employment center or subcenter for the particular cluster. Furthermore, employment in seventeen of the twenty clusters is found to be more spatially concentrated than manufacturing employment as a whole, suggesting that geographic proximity is important to interindustry linkages in the Southern California economy. More important, the spatial concentration across industry clusters varies considerably within the metropolitan area, implying that economic development practitioners should consider local context and adapt industry cluster theories to the specific advantages and disadvantages of their immediate locality. 相似文献
17.
《European Journal of Agronomy》2009,30(4):175-183
The ability to deliver wheat grain with a specific protein content is a major determinant of the profitability of wheat grain production. Various crop models have been developed to predict yield and grain protein content on a field scale. They can be used to predict each year, before harvest, the yields and grain protein contents of the different fields in a collecting area, leading to an optimization of the grading process into low and high protein standards. Indicators have been developed for nitrogen management at the field scale. They can be used to predict grain quality because grain protein content depends strongly on the crop nitrogen uptake during the vegetative growth of the wheat crop. The aim of this study was to evaluate the accuracy of two indicators, nitrogen nutrition index and chlorophyll content of leaves (in SPAD units), and of two models for categorizing fields according to their grain protein contents. A data set including field measurements over 3 years was used to estimate the sensitivity and specificity of the models and indicators using the receiver operating characteristic evaluation procedure. High values of sensitivity and specificity were obtained for the two indicators, and decision thresholds leading to low false negative and false positive proportions were identified. Nitrogen nutrition index showed the best results for the three grain protein content thresholds considered. Conversely, sensitivity and specificity values obtained for the two models were low. Combining model predictions and indicator values did not give better discrimination than the use of a single indicator. 相似文献
18.
构建科学有效的宅基地流转机制是一个迫切需要解决的基础性课题。笔者利用江西省456户农户的实际调查数据,运用Logit回归模型研究家庭经济禀赋、政策认知对农户宅基地流转意愿的影响。研究结果表明：家庭经济禀赋中非农收入比重、家庭存款、家庭人均年收入对农户宅基地流转意愿具有显著正向影响;政策认知中“一户一宅”认知、流转规定认知程度对农户宅基地流转意愿具有显著负向影响。为此,应进一步提高农户非农就业机会,改善农民务工经商的就业环境、应加快制定“一户一宅”的配套制度,构建更加合理和更具有操作性的宅基地流转政策体系。 相似文献
19.
Bradford F. Mills 《Growth and change》2001,32(2):174-192
Non‐metropolitan areas of the U.S have experienced significant structural economic changes in recent decades. These changes have raised concerns that some non‐metropolitan workers may face significant costs to employment displacements associated with economic adjustments. This paper explores the roles that linkages to metropolitan labor markets, area labor market conditions, and individual attributes play in determining the rates of exit from unemployment to employment among non‐metropolitan area residents. Adjacency to a metropolitan area is found to significantly increase transition rates from unemployment to employment among displaced non‐metropolitan workers, but local economic conditions are found to have relatively weak or insignificant effects on transition rates. Also, lack of post‐high school education and minority status both significantly reduce rates of exit from unemployment in non‐metropolitan areas following employmentdisplacement. 相似文献
20.
基于数据信息特征的土地资源评价客观赋权方法的研究 总被引：1，自引：1，他引：0
目前土地资源评价客观赋权方法种类繁多,而各种赋权方法对同一组指标数据的赋权结果不同,就常见客观赋权方法进行整理和归类,并以甘肃省庄浪县农村居民点整理数据为材料,从客观赋权方法原理出发,基于数据信息特征,引入变异系数、方差膨胀因子,根据指标体系中变异系数均值、方差膨胀因子均值的不同,创造性地构建差异组和相关组,在各指标体系下对赋权方法比较分析。结果表明：（1）利用差异信息赋权的熵权法、变异系数法、均方差法、离差最大化法,熵权法最优;（2）利用差异信息赋权的熵权法和利用重复信息赋权的复相关系数法的赋权结果无趋同性;（3）基于熵权法和复相关系数法的一种组合优化方法。 相似文献