Probabilistic prediction represents an outcome with a probability distribution rather than a single point value. This distribution expresses predictive uncertainty, helping Bayesian optimization balance risk and reward when choosing what to evaluate next. section 1.2.1
The distinction from point prediction is practical:
- A ridge regressor predicts one value at each test point; for example, it predicts 2.2 at test point 2. section 1.2.1
- A Gaussian process produces a probability distribution at each test point, revealing how uncertain the prediction is. section 1.2.1
- This uncertainty supports better risk–reward tradeoffs than predictions that provide no uncertainty measure. section 1.2.1
Figure 1.3 Non-Bayesian models, such as ridge regressors, make pointwise estimates, while GPs produce probability distributions as predictions. GPs thus offer a calibrated quantification of uncertainty, which is an important factor when making high-risk decisions.
Compare pointwise estimates with Gaussian-process distributions and their calibrated uncertainty visually. section 1.2.1
