交易策略的优化问题和机器学习深度学习的参数优化问题,有啥本质不同

一是因为你们的数据量对于问题复杂度来说,太少,二是因为你们的问题本身方差就极大,信噪比太低。所以你们的最优参数都是严重过拟合。其他机器学习领域也一样,都要控制过拟合。
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举个例子,GP和神经网络的区别:
Genetic programming is different from all other approaches to artificial intelligence, machine learning, neural networks, adaptive systems,reinforcement learning, or automated logic in all (or most) of the following seven ways:
(1) Representation: Genetic programming overtly conducts it search for a solution to the given problem in program space.
(2) Role of point-to-point transformations in the search: Genetic programming does not conduct its search by transforming a single point in the search space into another single point, but instead transforms a set of points into another set of points.
(3) Role of hill climbing in the search: Genetic programming does not rely exclusively on greedy hill climbing to conduct its search, but instead allocates a certain number of trials, in a principled way, to choices that are known to be inferior.
(4) Role of determinism in the search: Genetic programming conducts its search probabilistically.
(5) Role of an explicit knowledge base: None.
(6) Role of formal logic in the search: None.
(7) Underpinnings of the technique: Biologically inspired.

原文:
【交易策略的优化问题和机器学习深度学习的参数优化问题,有啥本质不同】 sevendiffs

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是这样:我原来采用参数的时候,是需要看这个参数周围,偏差百分之五的范围内的所有参数,都能取得较优的结果,那就采用这个参数值。 可是放在深度学习里面,我无法控制参数偏移量,是不是就无法做这件事情了? 又或者,因为参数是一点点“偏导数修正”而来,本身就已经保证了“参数周围的一定范围内”也是较优的? 那么我怎么取得,有最大较优范围的那个参数呢?貌似深度学习里面的参数都是不能做比对的,因为参数太多了。还有一个问题2:机器学习的目标是寻找让“成本函数”最小的“最优参数”,这本身就是是对“已有的训练集,验证集,测试集”――所有已知数据的“过拟合”。模型研究者看着在测试集上跑的结果,可以接受,然后就认可了这个模型。――测试集也只是没有用来改变参数而已。解决这个问题2的思路在于利用抽样方法:简单随机抽样,系统抽样,分层抽样等。这些抽样貌似在深度学习里面,没怎么提过。


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