Aggregation in Geostatistical Problems
Aggregation in Geostatistical Problems
复制标题
地统计问题中的聚合
DOI:
10.1007/978-94-011-1739-5_3
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发表时间:
1993
期刊:
影响因子:
--
通讯作者:
N. Cressie
中科院分区:
文献类型:
--
作者:
N. Cressie
A random process Z(·) defined on point support has quite different characteristics to those of aggregations of Z(·). For example, \(Z\left( {\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\thicksim}$}}{s} } \right)\) has larger variance than \(Z\left( B \right) \equiv \int_B {Z\left( {\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\thicksim}$}}{u} } \right)} d\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\thicksim}$}}{u} / \int_B {d\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\thicksim}$}}{u} } \), where \({\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\thicksim}$}}{s} }\) is a point chosen at random within the block B; B is often referred to as the support of Z(B). Suppose that a resource Z(·) is sampled, yielding data \(Z \equiv {\left( {Z\left( {{{\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\thicksim}$}}{s} }_1}} \right), \ldots ,Z\left( {{{\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\thicksim}$}}{s} }_n}} \right)} \right)^\prime }\). However, the resource is extracted in blocks B1,…, BN. Let B denote a generic block and suppose that it is desired to predict g(Z(B)) based on the data \({\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\thicksim}$}}{Z} }\). The conditional expectation, \(E\left\{ {g\left( {Z\left( B \right)} \right)\left| {\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\thicksim}$}}{Z} } \right.} \right\}\), minimizes the mean-squared prediction error, but it is impossible to estimate it without making over-utopian parametric assumptions. Current approaches to the problem require knowledge of “block-to-block”, and “block-to-sample”, parameters that cannot be estimated from the data. This paper proposes alternatively to make the kriging predictor more variable; the result is an optimal predictor for g(Z(B)) that is unbiased for a Gaussian process and approximately unbiased for a non-Gaussian process and sufficiently smooth g.
DOI:
10.2307/2987329
发表时间:
1970-06
期刊:
--
影响因子:
--
作者:
M. Degroot
通讯作者:
M. Degroot