Probabilistic Graphical Models:一、Introduction and Overview(2、Factors)

一、什么是factors?

类似于function,将一个自变量空间投影到新空间。这个自变量空间叫做scope。

二、例子

如概率论中的联合分布,就是将不同变量值的组合映射到一个概率,概率和为1.

三、几种操作(factor operation)的介绍

1、乘积

2、边缘化

3、缩减

四、总结(为何引入factor?)

1、对于定义高维空间的分布具有关键意义;

2、包括了概率分布的基本操作。

时间: 2024-10-18 19:57:19

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