Logistic Regression is a classification technique that predicts the probability of the default or reference category of the outcome variable. In this approach, the logarithm of the odds of the outcome is expressed as a linear combination of the input features. The log-likelihood function in logistic regression serves as a loss function that aggregates all the individual log likelihoods from each point in the training set into a unified formula. This loss function is essentially the opposite of maximizing the probability of the training set. Regarding Maximum Likelihood Estimation (MLE), it is a widely-used method for estimating model parameters by maximizing the likelihood function, which indicates how effectively the model accounts for the observed data. Thus, we optimize our parameters by identifying the values that maximize the likelihood or, equivalently, minimize the negative log-likelihood. To summarize, the log-likelihood loss function in logistic regression and maximum likelihood estimation are closely related. MLE is employed to determine the parameters of logistic regression by minimizing the log-likelihood loss function, thereby maximizing the likelihood of the training data being accurately classified.