Please merge tag modelling (20 questions) into modeling (138), and make them synonyms.
Neither of tags has wiki, but questions in both appear to be about the same topic and per my reading of Grammar Blog article both spellings mean the same thing.
On a related note, merging these two tags with model (97 questions) also looks worth considering.
Preference for master tag is because it has more questions.
This suggestion was made in Whiteboard chat (twice) but somehow, not actioned. Hence, posting to meta.