Talk:Heterogeneous relation

Southern ocean
This project supports the notion of a Southern Ocean, larger than the Arctic Ocean but smaller than the other three. Carving out a boundary has been arbitrarily slit at 60 degrees South or at the Antarctic convergence. Antarctica is generally considered the only continent with a boundary in the Southern Ocean, but South America comes close. Furthermore, Heard Island and New Zealand Subantarctic Islands of Oceania (at 53 degrees and 52.5 degrees South latitude) reach close to the waters of the Southern Ocean. The Ocean-Continent relation in Examples of this article might be adapted to the inclusion of this fifth ocean. The isolation of AA gets confirmed, but the question of contact with SA and OC lends uncertainty.— Rgdboer (talk) 22:04, 1 September 2018 (UTC)

Improving this article with consideration of the Southern Ocean might use the following table:

Here the contact of South America and Oceania with the Southern Ocean is asserted. Rgdboer (talk) 22:20, 3 September 2018 (UTC)

Merge with binary relation
This article appears to duplicate binary relation; the very first sentence in fact simply gives a definition of a binary relation (which is a subset of $$A \times B$$ with no requirement $$A = B$$). Therefore, this article needs to be merged with binary relation. -- Taku (talk) 00:33, 4 February 2019 (UTC)
 * Please review Homogeneity and heterogeneity for insight to meaning. This article concerns relations R ⊂ A x B where A ≠ B. — Rgdboer (talk) 02:50, 5 February 2019 (UTC)
 * Well, that wasn't what the first paragraph said; but now I understand this article is not a duplicate (so will withdraw the proposal). -- Taku (talk) 04:17, 5 February 2019 (UTC)
 * Thank you! — Rgdboer (talk)