Consider these three questions (in chronological order):
- What exactly is a hyperparameter?
- What do we mean by hyperparameters?
- What's in a name: hyperparameters
I think it's pretty clear that they are exact duplicates (currently only #2 is closed as a dup of #1). However, all three contain excellent answers. I would therefore suggest to merge all three questions into one of them.
I think the best candidate for the "master thread" is #3, because it has most answers, most upvotes, and most views, despite being the newest.
I flagged these threads for mod attention, but as per @Glen_b's suggestion I post this on meta too so that everybody could take a look and vote. Please upvote the question iff you agree that merging is a good idea.