# Score functions

In this section, we would like to introduce score functions in causal-learn. Currently we have BIC score 1, BDeu score 2, generalized score with cross validation or marginal likelihood 3.

Contents:

- BIC score
  - Usage
  - Parameters
  - Returns
- BDeu score
  - Usage
  - Parameters
  - Returns
- Generalized score with cross validation
  - Generalized score with cross validation for single-dimensional variables
  - Generalized score with cross validation for multi-dimensional variables
- Generalized score with marginal likelihood
  - Generalized score with marginal likelihood for single dimensional variables
  - Generalized score with marginal likelihood for multi-dimensional variables

1

  Schwarz, G. (1978). Estimating the dimension of a model. The annals of statistics, 461-464.

2

  Buntine, W. (1991). Theory refinement on Bayesian networks. In Uncertainty proceedings 1991 (pp. 52-60). Morgan Kaufmann.

3

  Huang, B., Zhang, K., Lin, Y., Schölkopf, B., & Glymour, C. (2018, July). Generalized score functions for causal discovery. In Proceedings of the 24th ACM SIGKDD International Conference on Knowledge Discovery & Data Mining (pp. 1551-1560).