What does RMSE stand for in the context of evaluating model performance?

Root Mean Squared Error (RMSE) is a commonly used metric for evaluating the performance of regression models. It measures the average magnitude of the errors between predicted values and the actual values in the dataset. By taking the square root of the mean of the squared differences, RMSE provides a sense of the average distance between the predicted values and the actual outcomes, representing the model's accuracy.

The RMSE is particularly useful because it penalizes larger errors more than smaller ones due to the squaring of the differences, making it sensitive to outliers. A lower RMSE value indicates a better fit of the model to the data, helping practitioners assess how well the model can predict future observations.

Other choices, while incorporating similar terminology, do not represent a recognized or standard term used in model evaluation. Therefore, the correct answer captures the widely accepted and meaningful metric for assessing model performance in data science.