Which of the following is NOT a category of machine learning?

The option identified as "Interventionist" is not a recognized category of machine learning. The three main categories of machine learning include supervised, unsupervised, and reinforced learning.

Supervised learning involves training a model on a labeled dataset, where the algorithm learns to map inputs to the correct outputs based on provided examples. This approach is typically used in applications such as classification and regression.

Unsupervised learning, on the other hand, deals with datasets that do not have labeled outcomes. The goal here is to identify patterns or structures within the data, often used in clustering and anomaly detection.

Reinforcement learning refers to a type of machine learning where an agent learns to make decisions by taking actions in an environment to maximize cumulative reward. This involves learning from the consequences of actions rather than from labeled input-output pairs.

In this context, "Interventionist" does not fit within the established framework of machine learning categories, which is why it is correctly identified as the option that does not belong.