《Make Your Own Neural Network》的笔记-第1页
- 页码：第1页 2018-06-17 12:03:36
Now imagine we don’t know the formula for converting between kilometres and miles. All we know is the the relationship between the two is linear. That means if we double the number in miles, the same distance in kilometres is also doubled.
, all we get is that the final update simply matches the last training example closely. We might as well have not bothered with all previous training examples. In effect we are throwing away any learning that previous training examples might gives us and just learning from the last one.
This way we move in the direction that the training example suggests, but do so slightly cautiously, keeping some of the previous value which was arrived at through potentially many previous training iterations.
The moderating factor is often called a learning rate, and we’ve called it L. Let’spick L= 0.5 as a reasonable fraction just to get started. It simply means we only update half as much as would have done without moderation.
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