Deep learning lecture 3
2017-12-25 本文已影响11人
飞奔的红舞鞋
RNN
Language modeling
目标:估计一个word sequence的概率
举个例子: recognize speech or wreck a nice beach, 从声音讯号里是判断不出来,但我们可以估计出来recognize speech的概率会更大一些
传统的方法是N-gram Language Modeling
n-1 个字的概率
![](https://img.haomeiwen.com/i6855379/062515cbea0f3aec.png)
smoothing 表示给某些情况一些小概率,例如p=0.0001
这些概率是不准确的,我们在training data里不能收集到所有情况
![](https://img.haomeiwen.com/i6855379/cae8baf56c13e480.png)
![](https://img.haomeiwen.com/i6855379/a2e5d56ff0fdc823.png)
Neural language modeling里,会自动做smoothing
RNNLM: recurrent neural network language model
![](https://img.haomeiwen.com/i6855379/840b7aafe7c13ba2.png)