Python: Deep neural networks

Question

I am currently working on some project related to machine learning.

I extracted some features from the object.

So I train and test that features with NB, SVM and other classification algorithms and got result about 70 to 80 %

When I train the same features with neural networks using nolearn.dbn and then test it I got about 25% correctly classified. I had 2 hidden layers.

I still don't understand what is wrong with neural networks.

Answer 1

Try increasing the number of hidden units and the learning rate. The power of neural networks comes from the hidden layers. Depending on the size of your dataset, the number of hidden layers can go upto a few thousands. Also, please elaborate on the kind, and number of features you're using. If the feature set is small, you're better off using SVMs and RandomForests instead of neural networks.