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 共查询到18条相似文献,搜索用时 109 毫秒
1.
熵与不确定度区间   总被引:8,自引:0,他引:8  
测量平差问题中,讨论观测量和参数估值时引入熵及熵意义上确定度区间的概念,并谁了不确定度区间评定精度的指标的可行性,进而提出以不确定度区间作为假设检验的置信区间,避免了选取显著性水平a时的非客观因素的影响,给出了t分布,x^2分布、F分布不确定度区间的计算公式及相应用数表。  相似文献   

2.
未知分布误差的熵不确定度   总被引:2,自引:1,他引:2  
分析现有估计方法的不足,提出基于最大熵的不确定度估计。所得的指标不受置信水平选取时的主观性影响,适合于GIS中未知分布误差的不确定性度量。  相似文献   

3.
给出了p-范分布子样的3个抽样分布——χp分布、tp分布及Fp分布的分布函数及数学期望、方差与不确定度区间的计算公式,并对若干有关分布的应用问题进行讨论。  相似文献   

4.
熵理论在确定点位不确定性指标上的应用   总被引:3,自引:0,他引:3  
分析了传统点位不确定性指标的局限性,基于信息论中的联合熵和最大熵定理导出了n维随机点熵不确定指标以及落入其内概率的统一公式;提出了以熵误差椭圆与熵误差椭球作为2维、3维GIS中点元的位置不确定性度量指标。提出的熵指标具有唯一确定、不受置信水平选取的主观性影响等特点,适合于度量未知分布的点位不确定性。  相似文献   

5.
分析了传统点位不确定性指标的局限性,基于信息论中的联合熵和最大熵定理导出了n维随机点熵不确定指标以及落入其内概率的统一公式;提出了以熵误差椭圆与熵误差椭球作为2维、3维GIS中点元的位置不确定性度量指标.提出的熵指标具有唯一确定、不受置信水平选取的主观性影响等特点,适合于度量未知分布的点位不确定性.  相似文献   

6.
误差熵不确定带模型   总被引:25,自引:2,他引:25  
本文从信息论的基本理论出发,通过熵的极值定理和引入误差熵的概念 ,首次提出了误差熵不确定带模型。该模型与以往的误差模型有着本质的区别。它不是任何意义上的置信带,而是一种完全确定的,与置信水平无关的不确定带模型。  相似文献   

7.
GIS中面元的误差熵模型   总被引:8,自引:0,他引:8  
根据整个线元边缘分布的平均信息熵确定了“ε-带”的宽度,提出了线元的平均误差熵带模型,进一步扩展到面元的误差熵环模型。误差熵环的带宽取构成边界线的各线段误差熵的加权平均值。最后通过算例比较了面元的误差熵环和误差环模型,绘出了它们的可视化图形,得出了一些有益的结论。  相似文献   

8.
P-范分布复杂的概率密度函数表达式不利于熵的计算和实际应用,提出利用简单分布的熵组合近似估计P-范分布的熵,可简化计算过程。数值演算对比表明,P-范分布熵的近似估计误差均不超过0.09,尤其当1≤p≤2时,最大误差仅为0.008 8,可实证近似计算的有效性。  相似文献   

9.
GIS中空间数据不确定性的混合熵模型研究   总被引:4,自引:0,他引:4  
基于信息理论和模糊集合理论,针对GIS中部分空间数据既具有随机性又具有模糊性的特点,建立了空间数据不确定性的混合熵模型。以GIS中线元不确定性为例,讨论了线元不确定性的统计熵、模糊熵和混合熵估计方法,并针对特例给出了线元不确定性的熵带分布。  相似文献   

10.
根据信息论基本原理,提出了二维随机点的熵误差指标,该指标与以往的误差指标不同,它是一个在熵意义下唯一确定的,与置信概率无关的客观指标,把它作为二维点位置不确定性的度量指标具有特殊优越性。  相似文献   

11.
Spatial data uncertainty can directly affect the quality of digital products and GIS-based decision making. On the basis of the characteristics of randomicity of positional data and fuzziness of attribute data, taking entropy as a measure, the stochastic entropy model of positional data uncertainty and fuzzy entropy model of attribute data uncertainty are proposed. As both randomicity and fuzziness usually simultaneously exist in linear segments, their omnibus effects are also investigated and quantified. A novel uncertainty measure, general entropy, is presented. The general entropy can be used as a uniform measure to quantify the total uncertainty caused by stochastic uncertainty and fuzzy uncertainty in GIS.  相似文献   

12.
Spatial data uncertainty can directly affect the quality of digital products and GIS-based decision making. On the basis of the characteristics of randomicity of positional data and fuzziness of attribute data, taking entropy as a measure, the stochastic entropy model of positional data uncertainty and fuzzy entropy model of attribute data uncertainty are proposed. As both randomicity and fuzziness usually simultaneously exist in linear segments, their omnibus effects are also investigated and quantified. A novel uncertainty measure, general entropy, is presented. The general entropy can be used as a uniform measure to quantify the total uncertainty caused by stochastic uncertainty and fuzzy uncertainty in GIS.  相似文献   

13.
Spatial data uncertainty can directly affect the quality of digital products and GIS-based decision making. On the basis of the characteristics of randomicity of positional data and fuzziness of attribute data, taking entropy as a measure, the stochastic entropy model of positional data uncertainty and fuzzy entropy model of attribute data uncertainty are proposed. As both randomic-ity and fuzziness usually simultaneously exist in linear segments, their omnibus effects are also investigated and quantified. A novel uncertainty measure, general entropy, is presented. The general entropy can be used as a uniform measure to quantify the total un-certainty caused by stochastic uncertainty and fuzzy uncertainty in GIS.  相似文献   

14.
GIS中线元的误差熵带研究   总被引:6,自引:3,他引:3  
基于现有的线元位置不确定性模型大多与置信水平的选取有关,而置信水平的选取带有一定程度的主观性,因而不能惟一确定,引入信息熵理论,提出了线元的误差熵带模型,并将它与“E-带”进行了比较,计算了落入其内的概率。该模型根据联合熵惟一确定,与置信水平的选取无关。  相似文献   

15.
Positional error of line segments is usually described by using “g-band”, however, its band width is in relation to the confidence level choice. In fact, given different confidence levels, a series of concentric bands can be obtained. To overcome the effect of confidence level on the error indicator, by introducing the union entropy theory, we propose an entropy error ellipse index of point, then extend it to line segment and polygon, and establish an entropy error band of line segment and an entropy error donut of polygon. The research shows that the entropy error index can be determined uniquely and is not influenced by confidence level, and that they are suitable for positional uncertainty of planar geometry features.  相似文献   

16.
Positional error of line segments is usually described byusing “g-band”,however,its band width is in relation to the confidence level choice.In fact,given different confidence levels,a series of concentric bands can be obtained.To overcome the effect of confidence level on the error indicator,by introducing the union entropy theory,we propose an entropy error ellipse index of point,then extend it to line segment and polygon.and establish an entropy error band of line segment and an entropy error do-nut of polygon.The research shows that the entropy error index can be determined uniquely and is not influenced by confidence level,and that they are suitable for positional uncertainty of planar geometry features.  相似文献   

17.
GIS中三维空间直线的误差熵模型   总被引:1,自引:0,他引:1  
从信息熵的角度提出了三维空间直线的误差熵模型,该模型由以垂直直线的平面误差熵为半径的圆柱体和两端点的误差球组成,是一种完全确定的度量空间线元不确定性的模型。理论分析与实验表明,本文所提出的模型具有较好的效果。  相似文献   

18.
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