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71.
碳排放问题是区域旅游业发展不可忽视的环境问题之一。根据相关统计数据,按照"自下而上"分析法对2000-2015年山东省旅游业碳排放进行定量估算,并采用系统聚类法将山东省旅游业碳排放划分为高、中、低三类碳排放区域,具体剖析山东省旅游业碳排放的区域差异。结果表明:(1)碳排放总量、游客人均碳排放量和碳排放强度是衡量区域旅游业碳排放的重要指标。2000-2015年山东省旅游业碳排放总量持续增长,而游客人均碳排放量和旅游业碳排放强度则逐年下降,旅游业节能减排取得一定成效。(2)区域旅游业三大部门碳排放存在明显差异,旅游交通是区域旅游业碳排放的主要来源,旅游活动碳排放增长速度最快,而旅游住宿碳排放波动性较大。2000-2015年山东省旅游业累积碳排放总量为4 764.05万吨,其中,旅游交通、旅游住宿、旅游活动三大部门占比分别为66.52%、25.80%、7.68%。(3)区域旅游业碳排放水平空间差异显著。从空间分布上看,山东省旅游业碳排放总体上呈现东高西低、北高南低的特征,旅游业碳排放总量呈现出东部沿海 > 鲁中地区 > 鲁西地区,游客人均碳排放量和旅游业碳排放强度则是东部沿海 > 鲁西地区 > 鲁中地区;从碳排放指标上看,山东省大多数地市位于中高旅游业碳排放的行列,东部沿海是旅游业碳排放的主要来源区。  相似文献   
72.
中国省域碳排放的空间特征及影响因素   总被引:1,自引:0,他引:1  
通过核密度分布和莫兰指数对中国2000—2015年30省份碳排放强度的动态趋势及集聚特征进行测度,并利用空间杜宾模型对其主要影响因素进行分析。结果显示:(1)中国30省份碳排放强度呈下降趋势,新常态以来低碳步伐加快;(2)碳排放强度的空间集聚性具有高水平集中、低水平集聚特征,空间溢出效应不断增强;(3)本省经济规模、产业结构对本省碳排放强度具有显著的正向影响,专利产出具有显著的负向影响;相邻省份的外商投资规模及能源消费结构变化对本省碳排放具有显著的空间溢出作用。因此,未来中国加快产业结构调整幅度、优化相邻省份间的产业空间布局以及大力发展绿色技术进步是中国促进区域低碳转型的主要方向,同时生态城镇化以及继续改善外商直接投资质量也是减排潜力因子,省域间的减排空间溢出效果不容忽视。  相似文献   
73.
This paper is dedicated to the study of the composite quantile regression (CQR) estimations of time-varying parameter vectors for multidimensional diffusion models. Based on the local linear fitting for parameter vectors, we propose the local linear CQR estimations of the drift parameter vectors, and verify their asymptotic biases, asymptotic variances and asymptotic normality. Moreover, we discuss the asymptotic relative efficiency (ARE) of the local linear CQR estimations with respect to the local linear least-squares estimations. We obtain that the local estimations that we proposed are much more efficient than the local linear least-squares estimations. Simulation studies are constructed to show the performance of the estimations proposed.  相似文献   
74.
This paper considers the problem where the linear discriminant rule is formed from training data that are only partially classified with respect to the two groups of origin. A further complication is that the data of unknown origin do not constitute an observed random sample from a mixture of the two under- lying groups. Under the assumption of a homoscedastic normal model, the overall error rate of the sample linear discriminant rule formed by maximum likelihood from the partially classified training data is derived up to and including terms of the first order in the case of univariate feature data. This first- order expansion of the sample rule so formed is used to define its asymptotic efficiency relative to the rule formed from a completely classified random training set and also to the rule formed from a completely unclassified random set.  相似文献   
75.
Data envelopment analysis (DEA) is the most commonly used approach for evaluating healthcare efficiency [B. Hollingsworth, The measurement of efficiency and productivity of health care delivery. Health Economics 17(10) (2008), pp. 1107–1128], but a long-standing concern is that DEA assumes that data are measured without error. This is quite unlikely, and DEA and other efficiency analysis techniques may yield biased efficiency estimates if it is not realized [B.J. Gajewski, R. Lee, M. Bott, U. Piamjariyakul, and R.L. Taunton, On estimating the distribution of data envelopment analysis efficiency scores: an application to nursing homes’ care planning process. Journal of Applied Statistics 36(9) (2009), pp. 933–944; J. Ruggiero, Data envelopment analysis with stochastic data. Journal of the Operational Research Society 55 (2004), pp. 1008–1012]. We propose to address measurement error systematically using a Bayesian method (Bayesian DEA). We will apply Bayesian DEA to data from the National Database of Nursing Quality Indicators® to estimate nursing units’ efficiency. Several external reliability studies inform the posterior distribution of the measurement error on the DEA variables. We will discuss the case of generalizing the approach to situations where an external reliability study is not feasible.  相似文献   
76.
《Statistics》2012,46(6):1396-1436
ABSTRACT

The paper deals with an asymptotic relative efficiency concept for confidence regions of multidimensional parameters that is based on the expected volumes of the confidence regions. Under standard conditions the asymptotic relative efficiencies of confidence regions are seen to be certain powers of the ratio of the limits of the expected volumes. These limits are explicitly derived for confidence regions associated with certain plugin estimators, likelihood ratio tests and Wald tests. Under regularity conditions, the asymptotic relative efficiency of each of these procedures with respect to each one of its competitors is equal to 1. The results are applied to multivariate normal distributions and multinomial distributions in a fairly general setting.  相似文献   
77.
通过建立包括陆地、湿地和海洋的碳承载力、碳超载率的计算模型,采用供需平衡法建立了区域碳锁定时间和趋势的判定模型。以有着“植物王国”和“基因宝库”之称以及水电资源相对丰富的云南省为例,对该省的碳锁定时间、趋势进行了实证研究。实证分析结果显示,云南省自2002年后开始出现了碳锁定现象且趋势越来越严重,若不进行强有力的外界干扰,这种趋势将一直延续下去。结合即使“十一·五”低碳目标的完成也没能减轻云南省碳锁定加剧的趋势,提出把减轻碳超载、控制能源消费总量、提升碳承载力纳入低碳经济发展的目标管理。  相似文献   
78.
The hazard rate (HR) and mean residual lifetime are two of the most practical and best-known functions in biometry, reliability, statistics and life testing. Recently, the reversed HR function is found to have interesting properties useful in additional areas such as censored data and forensic science. For these three biometric functions, we propose testing methods that they take on a known functional form against that they dominate or are dominated by this known form. This goodness-of-fit-type testing is wider in applications and more interesting than the long-standing testing procedures for exponentiality against the monotonicity of these functions or even the change point problems. This is so since we can test against any choice of the survival distribution and not just exponentiality. For this general testing, we present easy to implement tests and generalize them into classes of statistics that could lead to more powerful and efficient testing.  相似文献   
79.
We consider a problem of evaluating efficiency of Decision Making Units (DMUs) based on their deterministic performance on multiple consumed inputs and multiple produced outputs. We apply a ratio-based efficiency measure, and account for the Decision Maker׳s preference information representable with linear constraints involving input/output weights. We analyze the set of all feasible weights to answer various robustness concerns by deriving: (1) extreme efficiency scores and (2) extreme efficiency ranks for each DMU, (3) possible and necessary efficiency preference relations for pairs of DMUs, (4) efficiency distribution, (5) efficiency rank acceptability indices, and (6) pairwise efficiency outranking indices. The proposed hybrid approach combines and extends previous results from Ratio-based Efficiency Analysis and the SMAA-D method. The practical managerial implications are derived from the complementary character of accounted perspectives on DMUs׳ efficiencies. We present an innovative open-source software implementing an integrated framework for robustness analysis using a ratio-based efficiency model on the diviz platform. The proposed approach is applied to a real-world problem of evaluating efficiency of Polish airports. We consider four inputs related to the capacities of a terminal, runways, and an apron, and to the airport׳s catchment area, and two outputs concerning passenger traffic and number of aircraft movements. We present how the results can be affected by integrating the weight constraints and eliminating outlier DMUs.  相似文献   
80.
大型体育场馆投资金额大、管理复杂,早期规划直接影响后期经济效益,同时片面追求设计和形体美,使得体育场馆能耗严重,这与国家提倡的低碳建筑可持续发展观是背道而驰。文章以第七届农运会体育场馆为例,在充分分析农运会体育场馆建设及其特点的基础上,提出合理规划管理第七届农运会大型体育场馆的建设对策性建议,使之更好的为本国的体育发展服务。  相似文献   
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