### Logistic Regression 2 – Cost Function, Gradient Descent and Other Optimization Algorithms

We have discussed the basic ideas of logistic regression in previous post. The purpose of logistic regression is to find the optimal decision boundary which can classify the data with different categorical target feature into different classes. We also introduced the logistic function or sigmoid function as the regression model to find the optimal decision boundary. Now let’s take a look how to achieve it.
Cost Function and Gradient Descent for Logistic Regression We can still use gradient descent to train the logistic regression model.