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arXiv 1104.2224math.STstat.TH
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离散样本空间上的适当局部评分规则

Proper local scoring rules on discrete sample spaces

A. Philip Dawid, Steffen Lauritzen, Matthew Parry

摘要:

评分规则是一个损失函数,根据$X$的实现结果$x$,衡量随机变量$X$的引用概率分布$Q$的质量;如果在$X$的任何分布$P$下,通过引用$Q=P$使期望得分最小化,则是适当的。利用有限样本空间${\mathcal{X}}$上的任何可微的适当评分规则是凹齐次函数的梯度这一事实,我们考虑这样的规则何时可以是局部的,在这个意义上,仅取决于$x$的指定邻域中的点的概率。在温和的条件下,我们刻画了这样一个适当的局部评分规则的齐次函数的集合上的团的无向图空间${\mathcal{X}}$。这样的规则的有用属性是所引用的分布$Q$仅需要知道到比例因子。使用这种评分规则的例子包括Besag的伪似然和Hyvärinen的比率匹配方法。

英文摘要:

A scoring rule is a loss function measuring the quality of a quoted probability distribution $Q$ for a random variable $X$, in the light of the realized outcome $x$ of $X$; it is proper if the expected score, under any distribution $P$ for $X$, is minimized by quoting $Q=P$. Using the fact that any differentiable proper scoring rule on a finite sample space ${\mathcal{X}}$ is the gradient of a concave homogeneous function, we consider when such a rule can be local in the sense of depending only on the probabilities quoted for points in a nominated neighborhood of $x$. Under mild conditions, we characterize such a proper local scoring rule in terms of a collection of homogeneous functions on the cliques of an undirected graph on the space ${\mathcal{X}}$. A useful property of such rules is that the quoted distribution $Q$ need only be known up to a scale factor. Examples of the use of such scoring rules include Besag's pseudo-likelihood and Hyvärinen's method of ratio matching.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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