0


直链条件随机场渐近理论

Asymptotic Theory for Linear-Chain Conditional Random Fields
课程网址: http://videolectures.net/aistats2011_sinn_asymptotic/  
主讲教师: Mathieu Sinn
开课单位: 滑铁卢大学
开课时间: 信息不详。欢迎您在右侧留言补充。
课程语种: 英语
中文简介:
本文发展了线性链条件随机场的渐近理论,并将其应用于模型权重最大似然估计(MLE)强一致的条件。我们首先定义了无限序列的L-CRF,并分析了它们的一些基本性质。然后,我们建立了观测的遍历性暗示观测和标签联合序列遍历性的条件。该结果是获得MLE强一致性条件的关键因素。有趣的发现是,一致性关键地依赖于似然函数的Hessian的极限行为,并且,渐进地,状态特征函数并不重要。
课程简介: In this theoretical paper we develop an asymptotic theory for Linear-Chain Conditional Random Fields (L-CRFs) and apply it to derive conditions under which the Maximum Likelihood Estimates (MLEs) of the model weights are strongly consistent. We first define L-CRFs for infinite sequences and analyze some of their basic properties. Then we establish conditions under which ergodicity of the observations implies ergodicity of the joint sequence of observations and labels. This result is the key ingredient to derive conditions for strong consistency of the MLEs. Interesting findings are that the consistency crucially depends on the limit behavior of the Hessian of the likelihood function and that, asymptotically, the state feature functions do not matter.
关 键 词: 机器学习; 最大似然估计; 函数
课程来源: 视频讲座网
最后编审: 2019-12-19:cwx
阅读次数: 34