Ricenaros

Ricenaros t1_jeax41q wrote

I would suggest picking up either pytorch or tensorflow and sticking with one of these while you learn (personally I'd choose pytorch). It'll be easy to go back and learn the other one if needed once you get more comfortable with the material.

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Ricenaros t1_jeawpf3 wrote

It refers to the number of scalars needed to specify the model. At the heart of machine learning is matrix multiplication. Consider input vector x of size (n x 1). Here is a Linear transformation: y = Wx + b. In this case, the (m x n) matrix W(weights) and the (m x 1) vector b(bias) are the model parameters. Learning consists of tweaking W,b in a way that lowers the loss function. For this simple linear layer there are m*n + m scalar parameters (The elements of W and the elements of b).

Hyperparameters on the other hand are things like learning rate, batch size, number of epochs, etc.

Hope this helps.

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Ricenaros t1_j0zqyxw wrote

using vectorized operations isn't just a design choice of the language you're programming in. It's a fundamental concept for optimizing code. for loops don't magically become fast just because you're using C++. For example, google "vectorize for loop c++" there are tons of results. In general you don't want to be using loops, especially for large scale data problems.

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Ricenaros t1_izkmdxd wrote

I'm trying to understand concepts involving feature engineering and correlation, because I feel like I'm encountering conflicting ideas about these two points. On the one hand, we can generate new features by combining our existing features, for example multiplying feature 1 by feature 2. This is said to improve ML models in some cases.

On the other hand, I have read that a desirable property of our input/output data is predictors being highly correlated with the target variable, but not correlated with other predictors. This idea seems to conflict with feature engineering, as our newly derived features can be correlated with the features they were constructed from. Am I missing something here?

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