graykode / nlp-tutorial

Natural Language Processing Tutorial for Deep Learning Researchers
https://www.reddit.com/r/MachineLearning/comments/amfinl/project_nlptutoral_repository_who_is_studying/
MIT License
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no embedding in nnlm? #10

Closed shawnthu closed 5 years ago

shawnthu commented 5 years ago

I can not find the embedding in nnlm!

graykode commented 5 years ago

Hello. pic from bengio03a paper image Did you see paper bengio(2003)?! Do you mean about point like nn.Embedding as C matrix in paper?

thedogb commented 5 years ago

@graykode ,it seems that you drop Wx in your implement.And your x is one-hot encoding of every word. But there should be a C matrix to train a feature vector for every word in bengio's paper.

graykode commented 5 years ago

@thedogb I found what i missing thanks I mistake with W, capital letter with 'w' lower.

def forward(self, X):
        # here will be look up table like C matrix in Paper
        input = X.view(-1, n_step * n_class) # [batch_size, n_step * n_class]
        tanh = nn.functional.tanh(self.d + torch.mm(input, self.H)) # [batch_size, n_hidden]
        output = self.b + torch.mm(input, self.W) + torch.mm(tanh, self.U) # [batch_size, n_class]
        return output

Is it right? @thedogb

graykode commented 5 years ago

@thedogb Hello again. There are two value which is show number of dimension m and h image(image reference is here) so I will change my code

# NNLM Parameter
n_step = 2 # n-1 in paper
n_hidden = 2 # h in paper
m = 2 # m in paper

# Model
class NNLM(nn.Module):
    def __init__(self):
        super(NNLM, self).__init__()
        self.C = nn.Embedding(n_class, m)
        self.H = nn.Parameter(torch.randn(n_step * m, n_hidden).type(dtype))
        self.W = nn.Parameter(torch.randn(n_step * m, n_class).type(dtype))
        self.d = nn.Parameter(torch.randn(n_hidden).type(dtype))
        self.U = nn.Parameter(torch.randn(n_hidden, n_class).type(dtype))
        self.b = nn.Parameter(torch.randn(n_class).type(dtype))

    def forward(self, X):
        X = self.C(X)
        X = X.view(-1, n_step * m)
        tanh = nn.functional.tanh(self.d + torch.mm(X, self.H)) # [batch_size, n_hidden]
        output = self.b + torch.mm(X, self.W) + torch.mm(tanh, self.U) # [batch_size, n_class]
        return output
thedogb commented 5 years ago

@graykode Hello. sorry, I don't know pytorch so much. I read code of NNLM-Tensor.py. In this implement, there is not Wx and C matrix. I modify it a little to add C matrix and keep Wx dropped, because W can be 0 when no direct connections from word features to outputs are desired . as follow:

m = 5
C = tf.Variable(tf.random_normal([1,n_class, m]))
C_shared = tf.tile(C, [tf.shape(X)[0],1,1]) # share parameter
vecs = tf.matmul(X,C_shared) # [batch_size, n_step, m], get feature vectors for every word

input = tf.reshape(vecs, shape=[-1, n_step * m]) # [batch_size, n_step * m]
H = tf.Variable(tf.random_normal([n_step * m, n_hidden]))
d = tf.Variable(tf.random_normal([n_hidden]))
U = tf.Variable(tf.random_normal([n_hidden, n_class]))
b = tf.Variable(tf.random_normal([n_class]))

Is it right? I'm a new learner of tensorflow, so if I make any mistakes,Please tell me. Thanks.

graykode commented 5 years ago

@thedogb m=2 in my code, I think we make C matrix, (n_class, m) I will edit NNLM with tensorflow soon

graykode commented 5 years ago

@shawnthu see my commit! https://github.com/graykode/nlp-tutorial/commit/52c4514bb56eebf63c5ce4f5f3dc323782278f77