Dataset card: IDs section links to docs/data.md in the code repo

README.md

@@ -53,8 +53,6 @@ data/
 ```
 
 ## IDs
-- `ftable_clean.csv` and `ntable_clean.csv`: `network_id` > 0 is a molecular network. A singleton feature is its own network, with `network_id` = -`feat_id`.
-- `proteomes_all.csv`: 4 columns per orthogroup tool, with the prefix `sonicpd_` (SonicParanoid) or `orthofinder_` (OrthoFinder): `_id`, `_size` (genes), `_sp_in_grp` (species), `_intersp` (species joined with `;`).
-- A singleton transcript is its own orthogroup, with a negative ID (-1, -2, ...). `sonicpd_id` starts at 1. `orthofinder_id` is the number in the OrthoFinder ID (`OG0000123` is 123), so it starts at 0.
+Column and ID conventions: [docs/data.md](https://github.com/titodamiani/PiperNET/blob/master/docs/data.md).
 
 `scripts/README.md` in the [code repository](https://github.com/titodamiani/PiperNET) describes how each file is made.