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Question 1. How to input multiple variables (features) x1, x2, x3...x10 which are in categorical in nature to neural network. Basically I want to know how will I prepare my input layer to neural network. Below is the sample example of my data set.
x1, x2, x10 Y A, Red A10 1 B, Blue A20 2 C, Green A30 3
I have googled on this, some say use one-hot encoding. But I am not sure how will I apply one hot encoding technique to all the feature I have and how the input matrix structure will be.
If I have only one feature say x1. I understand I can apply one-hot encoding.
A: 1 0 0 B: 0 1 0 C: 0 0 1
And this 3x3 matrix can be used as input layer to Neural network.
[3x3] -> [Neural Network] -> [out]
But I have multiple feature here x1, x2 ... x10. How will I frame my input layer, what will the input layer structure. Please advise.
Also, variable x2, x10 might get new categorical value which is not seen in training set (for eg. X10 = Z99 ) how to handle this problem.