Expected improvement
Expected improvement is a Bayesian optimization acquisition function that estimates a candidate’s expected gain over the best observed objective value while accounting for predictive uncertainty.
Bayesian Optimization in Action
Expected improvement is a Bayesian optimization acquisition function that quantifies the expected amount by which evaluating a candidate may improve on the best observed objective value.
- How it is used
- Ranks candidate evaluations in Bayesian optimization by expected improvement over the incumbent.
- How deep it goes
- Develops EI from improvement intuition through probabilistic magnitude, closed-form scoring, BoTorch use, and a batch extension.
- Examples
- Uses validation-accuracy tuning, a one-dimensional objective search, and BoTorch acquisition construction.
- What you can do after
- Apply it via BoTorch to select and optimize the next Bayesian optimization query.
Read how Bayesian Optimization in Action explains expected improvement →
AI-Powered Search
Expected improvement is a Bayesian-optimization acquisition function that scores candidates by their expected gain over the current best result while accounting for predictive uncertainty.
- How it is used
- Guides active-learning exploration by choosing search candidates with the highest predicted upside for live-user evaluation.
- How deep it goes
- Explains the basic formula and implementation, but defers advanced Bayesian-optimization details.
- Examples
- Uses product features, logged judgments, uncertainty tables, and a "transformers dvd" exploration query.
- What you can do after
- Apply it via Python to rank candidate feature vectors and select products for search-engine exploration.
Related concepts
- constrained expected improvementincludes · Constrained expected improvement is a Bayesian optimization acquisition function whose score is the expected improvement multiplied by the probability that the candidate satisfies the constraints.
- ExpectedHypervolumeImprovementincludes · ExpectedHypervolumeImprovement is a BoTorch acquisition-function class that computes analytic expected hypervolume improvement for multiobjective Bayesian optimization.
- Bayesian optimizationkind of · Bayesian optimization is a sequential method for optimizing an expensive or unknown objective by using a probabilistic model to guide evaluations.
- policykind of · A policy is a rule, model, or set of rules that determines behavior, decisions, or permitted actions under specified conditions.
- acquisition functionkind of · An acquisition function is a scoring rule that ranks candidate evaluations by their expected usefulness for selecting the next sample or experiment.
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