How are recommendations made, because sometimes I don't understand why. And sometimes manga doesn't have any recommendations at all.

I've been wondering where those come from too and why some manga don't have any. lol

Are they added by members or related to what those who put the manga into their lists read?

Staff folk add the recs, I believe. Either that, or its judged by series other people read as well...
Like say if 20 people read Naruto. 13 of which read One Piece, so One Piece appears on the recommendations list.

ooooh.so thats how it works.i thought that recommendations are made through their genres.like what they have in common.

but i think the updaters are lazy cuz there are a ton of series that have no recommendations

Haha, no, it has nothing to do with updaters. It's an automatic system that generates those recommendations. Basically what Highway-STAR said.

source: animenewsnetwork

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thats very clever. but @robbit, then why do some have no recommendations? are there too few commonplace series in the reading lists?

The series that have no recommendations usually have too little data to go by with, hence why they don't have any recommendations, it's as simple as that.

source: animenewsnetwork

Join SRoMU Scanlations or visit #SRoMU at IRCHighWay.