goodness-of-fit test

A goodness-of-fit test is a statistical method used to determine how well a set of observed data matches an expected distribution or model. Imagine you have a bag of colored marbles and you expect a certain number of each color based on probability. After counting the marbles, the goodness-of-fit test helps you see if the actual counts align with your expectations. If they do, the model is a good fit; if not, it suggests that the underlying assumptions about the data might need adjusting. Essentially, it assesses how well your assumptions hold up against reality.