Discovering numeric laws,a case study: CO 2 fugacity in the ocean

Abstract

The idea to automate the discovery of numeric laws goes back to early 1980's when some authors showed how to use to this end AI search techniques. Later, the community somewhat lost interest in this task, reasoning that it was unlikely that a computer program would ever "outperform" human intuition supported by background knowledge. Only recently did some authors manage to overcome this scepticism: their programs were able to discover new numeric laws in soft-science domains such as ecology and psychology. In the case study reported here, we describe a successful attempt to assist ocean chemists in their attempts to predict absorption rate of CO₂ in certain regions of the ocean. The system we have developed has found equations that outperform those suggested by field experts assisted by regression techniques. Our experience indicates that more attention should be paid to the following: the impact of spatio-temporal aspects, the existence of "hidden causes" (not directly reflected in a given set of variables), and the need for a field expert to post-process the results.