---
primary_layer: layer2
related_layers: []
page_type: entry
---

# Algorithms

Pages summarizing how named algorithms from the literature are reproduced as combinations of saealib components.

When a configuration does not exactly match the theoretical definition, each page states the implementation differences, such as acquisition-function constraints, selection or archive handling, and evaluation order.

::::{grid} 1 2 2 3
:gutter: 3

:::{grid-item-card} EGO
:link: ego
:link-type: doc

Sequential model-based optimization combining Gaussian Process regression with the Expected Improvement acquisition function.
:::

:::{grid-item-card} GP-UCB
:link: gp_ucb
:link-type: doc

Sequential model-based optimization combining Gaussian Process regression with the Upper Confidence Bound acquisition function.
:::

:::{grid-item-card} MaxUnc
:link: maxunc
:link-type: doc

Exploration-only sequential model-based optimization based solely on the predictive uncertainty of Gaussian Process regression.
:::

:::{grid-item-card} CORS-RBF
:link: rbf_cors
:link-type: doc

Sequential model-based optimization combining an RBF-interpolation surrogate model with a distance constraint from existing evaluated points.
:::

:::{grid-item-card} NSGA-II
:link: nsga2
:link-type: doc

Multi-objective genetic algorithm based on non-dominated sorting and crowding distance. The basis for saealib's multi-objective comparators.
:::

:::{grid-item-card} SPEA2
:link: spea2
:link-type: doc

Multi-objective genetic algorithm combining dominance-based strength and density into a fitness value, with a fixed-size archive.
:::

:::{grid-item-card} NSGA-III
:link: nsga3
:link-type: doc

Multi-objective genetic algorithm that uses reference-direction niche preservation.
Primarily targets many-objective optimization, while exposing reference-direction behavior with three objectives.
:::

:::{grid-item-card} SMS-EMOA
:link: sms_emoa
:link-type: doc

Steady-state multi-objective evolutionary algorithm that incorporates dominated hypervolume directly into the selection criterion.
:::

::::

```{toctree}
:hidden:

ego
gp_ucb
maxunc
rbf_cors
nsga2
spea2
nsga3
sms_emoa
```