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多类型点的空间过程分析方法AI 解读

Summary Two approaches are described to the analysis of spatial patterns consisting of several types of points. The first approach uses a method of asymptotically unbiased estimation of the second moment distribution; the second uses methods based on regions of empty space in the patterns. Some distributional results are given in each case, and a method of Monte Carlo testing conditional on the marginal structure is described. The methods are illustrated by being applied to…

摘要暂缺

多维格点上平稳过程的参数估计AI 解读

We study asymptotic properties of various estimation procedures for a general stationary regular process on a d-dimensional lattice. Differences between d = 1, time series, and d ≥ 2 spatial processes, are pointed out. We suppose that the process is observed on a set PN, with cN points, which tends to infinity with the same speed in all directions. The relative edge effect is of order cN−1/d, increasing with d: this effect is without statistical importance if d = 1, but is…

农业均匀性数据中空间模型拟合充分性的札记AI 解读

A model fitted by Patankar (1954) to Mercer & Hall's wheat data, and claimed to provide a satisfactory fit, is reexamined. It is shown that the method of fitting is unsatisfactory, and that even when fitted satisfactorily the model is not adequate. Some results on the efficiency of ordinary least squares are given in the Appendix.

家庭内部疾病传染性的推断AI 解读

The potential that an infective has for infecting a given susceptible from the same household is quantified as a random variable depending on the duration of the infectious period, the severity of the illness and the mobility of the infective. Procedures for making inference about both the mean value and the variance of this potential are proposed. In particular, the proposed analysis makes it possible to test whether infectives display significant differences in their…

农业均匀性数据空间模型拟合充分性的再检验AI 解读

A model fitted by Patankar (1954) to Mercer & Hall's wheat data, and claimed to provide a satisfactory fit, is reexamined. It is shown that the method of fitting is unsatisfactory, and that even when fitted satisfactorily the model is not adequate. Some results on the efficiency of ordinary least squares are given in the Appendix.

将社会网络作为随机过程分析AI 解读

This article presents a new methodology for studying a social network of interpersonal relationships, based on stochastic modeling of the changes that occur in the network over time. Specifically, we postulate that these changes can be modeled as a continuous-time Markov chain. The transition rates for the chain are dependent on a small set of parameters that measure the importance of various aspects of social structure on the probability of change. We discuss the…

平稳时空过程的分析：估计与预测AI 解读

The paper analyses a simultaneous linear model representing stationary spatial-temporal processes. For processes with unit spatial orders, a simple method to compute the likelihood function is developed. Unfortunately, this technique does not generalize to higher order processes. Alternative methods applicable to higher order processes are developed. Finally, it is shown how predictions can be made over time if the parameters are known.

空间过程统计分析中界的运用AI 解读

Explicit solutions for the equilibrium distributions of competitive spatial processes in which the rate of invasion is directly proportional to the number of neighbours of a certain type exist only in special cases. Nevertheless these models may be more realistic than those required to produce Markov random fields. As an alternative to Monte Carlo simulation we use local balance equations to find bounds for important properties of the limiting configuration such as the…

空间点模式的随机性检验AI 解读

Summary Tests of “randomness” and methods of edge-correction for spatial point patterns are surveyed. The asymptotic distribution theory and power of tests based on the nearest-neighbour distances and estimates of the variance function are investigated.

平稳时空过程分析：估计与预测AI 解读

The paper analyses a simultaneous linear model representing stationary spatial-temporal processes. For processes with unit spatial orders, a simple method to compute the likelihood function is developed. Unfortunately, this technique does not generalize to higher order processes. Alternative methods applicable to higher order processes are developed. Finally, it is shown how predictions can be made over time if the parameters are known.

空间过程统计分析中的界限方法AI 解读

Explicit solutions for the equilibrium distributions of competitive spatial processes in which the rate of invasion is directly proportional to the number of neighbours of a certain type exist only in special cases. Nevertheless these models may be more realistic than those required to produce Markov random fields. As an alternative to Monte Carlo simulation we use local balance equations to find bounds for important properties of the limiting configuration such as the…

摘要暂缺

空间点过程的参数估计AI 解读

Summary In a recent paper, Ripley (1977) discusses the use of two goodness-of-fit criteria for spatial point pattern data. Both criteria can be adapted to the associated problem of parameter estimation. to illustrate their use in this respect, we re-work one of Ripley's examples and reach rather different conclusions.

空间变量的一种关联度量AI 解读

A measure of association for spatial variables is proposed. The measure is based on the ranks of the observations and on the location coordinates of the measurement points. For two independent spatial variables it is shown that under optimal coordinate designs the variance of the measure is of the order l/(kn), where n is the number of data points and k is the dimension of the observation space. Conditions for asymptotic normality are stated, and asymptotic formulae for bias…

稀有人群二元属性估计中分层随机网络抽样的最优配置AI 解读

This work considers estimation of dichotomous characteristics of rare populations by sample survey. In particular, we investigate optimum allocation when a network sampling rule (also called multiplicity rule) is used to link members of the rare population to enumeration units and when the enumeration units are chosen by stratified random sampling. For this situation, formulas are derived for optimum allocation under the restriction that an enumeration unit is linked to at…

不透明空间样本的抽样理论AI 解读

Summary Procedures for inferring the internal geometric structure of an opaque bounded n-dimensional set by random sectioning are discussed. General conditions are given (evidently for the first time) for the validity of the so-called “fundamental formulae” of stereology (the science of inferring spatial structure from lower dimensional data). In technical terms, a wide class of unbiased ratio estimators, based on the traces of embedded features in appropriately weighted…

生态与疫情传播的空间接触模型AI 解读

Summary A wide variety of phenomena of geographical spread can be described in terms of a mechanism of “growth” (e.g. birth, infection) and a “contact distribution” which describes how the locations of the individual(s) involved in a migratory move, or infection at a distance, are spatially related. I shall survey work on such models, beginning with an examination of the relations between stochastic and deterministic models; it emerges that both linear and nonlinear…

空间点模式的稳健密度估计札记AI 解读

The author's earlier analytical results on the robustness of distance-based estimators of density are supplemented by a simulation study, with particular attention being given to various types of aggregated spatial point patterns. In addition, some remarks on heterogeneous patterns are made. Finally, the results of an application to data on tree locations are described.

实施 Fisher 迭代检验的算法AI 解读

THE ALGORITHM DESCRIBED here is used to generate all simultaneous submodels of an econometric model. F. M. Fisher's correspondence principle [1] for simultaneous equation models requires that all simultaneous submodels of the full model be solvable by a particular form of simple iteration, and suggests that the smallest simultaneous submodels be tested first. This algorithm does that by using the primitive v cycle (hereafter called seed) description of a simultaneous…

摘要暂缺

空间点模式稳健密度估计札记AI 解读

The author's earlier analytical results on the robustness of distance-based estimators of density are supplemented by a simulation study, with particular attention being given to various types of aggregated spatial point patterns. In addition, some remarks on heterogeneous patterns are made. Finally, the results of an application to data on tree locations are described.

利用新条件距离方法稳健估计林分密度AI 解读

Estimators for the density of points in a plane may be unbiased for the spatial pattern for which they were designed but are usually biased for most others. Two new estimators are proposed which are approximately unbiased for a wide range of patterns, and are used on data in the form of the positions of the centres of trees in a forest stand.

空间结构要素：一种定量方法AI 解读

1. Introduction Part I. Static Aspects of Regional Structure: 2. Regions as combinatorial structures 3. Regions as ordered series 4. Regions as surfaces Part II. Dynamic Aspects of Regional Structure: 5. Spatial comparison of time series: a framework 6. Spatial comparison of time series: I. Contagious processes 7. Spatial comparison of time series: II. Unemployment in South-West England Part III. Autocorrelation and Forecasting: 8. Spatial autocorrelation 9. The analysis of…