Michael Goodrich's Erdős-Bacon Number.

A person's Erdős number is the degrees of separation from that person to the famous mathematician Paul Erdős. That is, the distance, in number of collaborations, from that person to Erdős. In fact, we can define a collaboration graph, where we create a vertex for each person and link two people with an edge if they have collaborated on a published work (e.g., research paper, movie, or TV show).

In the entertainment world, there is a concept similar to the Erdős number. In that collaboration community, a person's Bacon number is the degrees of separation from that person to the actor, Kevin Bacon.

Taking the sum of a person's Erdős number and their Bacon number gives their Erdős-Bacon number.

Michael Goodrich's Erdős number is 3, which is realized in the following (disjoint) ways in the collaboration graph:

1. Erdős->Avis->Snoeyink->Goodrich
2. Erdős->Pach->Bronnimann->Goodrich
3. Erdős->Pollack->Agarwal->Goodrich
4. Erdős->Alon->Vishkin->Goodrich
5. Erdős->Aronov->Kosaraju->Goodrich
6. Erdős->Wagstaff->Atallah->Goodrich
7. Erdős->Silverman->Mount->Goodrich
8. Erdős->Fraenkel->Scheinerman->Goodrich
9. Erdős->Odlyzko->Guibas->Goodrich
10. Erdős->Yao->Eppstein->Goodrich

Goodrich's Bacon number is also 3, which is realized as follows:

1. Goodrich coauthored a paper with Jeff Westbrook, who is a writer for such shows as The Simpsons and Futurama.
2. Jeff Westbrook was a staff writer for Futurama's "X-mas Story" episode, starring John Goodman as the voice of the Santa Claus Robot.
3. John Goodman was in the movie, Death Sentence (2007), with Kevin Bacon.

Thus, Goodrich's Erdős-Bacon number is 6.

Note: there are some who define the Bacon number in terms of a collaboration graph whose edges are restricted to collaborations that are movies. Using this more restrictive definition, Westbrook and Goodrich would both have Bacon numbers of infinity.