To decrease a model's degrees of freedom and prevent model overfitting, you can consolidate _________________ inputs.

Consolidating categorical inputs is a key strategy for reducing a model's degrees of freedom, which can help prevent overfitting. Categorical variables are those that represent distinct categories or groups, rather than continuous values. When used in modeling, each unique category can introduce its own parameter, potentially leading to a complex model that captures noise rather than the underlying pattern in the data.

By consolidating categorical inputs, you can merge similar categories into fewer groups or create a new variable that reflects the essential information without retaining all the individual levels. This reduction simplifies the model, decreases the number of parameters, and enhances the model's ability to generalize to new, unseen data, which is crucial in achieving robust predictive performance.

In contrast, nominal, ordinal, and continuous inputs do not primarily address model complexity in the same way that categorical consolidation does, particularly since the decision to combine categories is largely specific to categorical variables. Reducing the number of categorical inputs directly impacts the model's flexibility and complexity.