NN does not train

1

Hi all,

I have a NN, you can see the picture below. I have small number of data (66). I split them into (44 train, 22 test). I’ve used binary_cross_entropy, After training the AUC is 0.5. I’ve tried other loss functions, but nothing changed.

image
image1356×1754 144 KB

Thanks

2

The dataset is tiny and I don’t know which layers your model contains.
Could you post the model definition here so that we could check for obvious issues?

3

here is the model:
n_feature = 9
n_genes = 691

class Net_simple(torch.nn.Module):
def init(self, n_feature, n_genes, n_output):
super(Net_simple, self).init()

    self.nn = torch.nn.Sequential(torch.nn.Linear(n_genes, 1))
    self.final = torch.nn.Sequential(torch.nn.Linear(n_feature, 1))
    
    self.predict1 =   torch.nn.Sigmoid()
    self.float()

def forward(self, x):
    x = x
    o1 = self.nn(x)
    o = self.final(o1.squeeze())
    w = self.predict1(o)
    return w

Thanks

4

My case is binary class. What kind of loss function is appropriate for the task?

5

Your model won’t work, as you are hitting a shape mismatch between self.nn and self.final.
The out_features of one linear layer are used as the in_features of the next one (in the common use case), so remove the squeeze in the forward and use:

self.nn = torch.nn.Sequential(torch.nn.Linear(n_genes, n_feature))