The trend of people spamming useless comments like "give minus" has been around for quite a while. In recent times however it has seen an inflation to such a extent that it has become a real nuisance. What's worse is that now there have been increasing cases of spamming in blogs as well. If left unchecked , I fear that they might grow into a serious issues someday in the future.
My solution to the problem is to follow the following steps:
People with a history of spamming comments should be banned from posting blogs or commenting. Alternatively people with a certain contribution (say -30 or less) shouldn't be allowed to comment or post blogs.
Unrated people shouldn't be allowed to comment or post a blog. A person has to attended a minimum of 4-5 contests to be eligible for commenting or posting a blog. This will ensure that people don't open fake accounts just for spamming. Also I think most people with less than 4 contests don't generally comment or post blogs.
Suggestions are welcome.
Yes, spamming is annoying, but here are some cases where your solution doesnt work imo:
if someone gets -30 contribution he will never have a chance to correct his contribution.
-If someone participates in one contest and then wants to ask a question about a problem, he cant.
-Some accounts are made in order to make an announcement for a contest, they should delay the contest until they participate in 4-5 contests or not make an announcement at all.
1.I think Upvotes/Downvotes for a post are automatically halved after 180 days, so it's posdible for them to contribute, but atleast after 6 months.
2.That's a loophole, unfortunately. If we prevent people from commenting, they will surely open fake accounts and do the same. So this is the sacrifice
Codeforces could have something like verified user feature that could solve that announcement issue.
Ad 1: the halving of contribution pretty much makes it a tempban.
Ad 2 (but also 1): moderation would solve it. If a mod could circumvent/negate those rules (e.g. have to approve of comments/blogs posted by unrated users or those with low contribution), it would probably work fairly well.
My proposed solution is simple, which Codeforces is lacking compared to all other places with upvote/downvote system: report a comment/blog post. After several people report the comment/blog post, they can be hidden for administrators to review (and may be displayed again if it's deemed okay), thus not disrupting anything else. Of course, the problem is that this is extra coding to the website.
I strongly disagree with your second proposal, exactly for the reasons explained by joudzouzou. And no, the sacrifice is too large compared to the payoff; turning new people away because they cannot comment is way worse than picking through the spam for the site.
slight nit-pick with your first point:
it's very easy for a spammy user to report non-spammy posts/comments by creating "several" ( ≤ 50) accounts. so instead of hiding and re-displaying after admins deem it ok, how about hiding after admin deems it spammy?
Good point. My idea was that there are some weights for reporting (people with more contribution weighs more, so like 1-2 people with high contribution reporting a post will immediately make it hidden while it takes a lot for people with zero/low contribution), but this is also unfair (either there's some weight for zero contribution, which means spammers will just make enough accounts to hide a comment, or there's no weight for it, which means people that don't have enough contribution can't hide comments/posts at all).
Hiding after admin deems it's spammy means admins need to work faster; the point of hiding stuff is to avoid it to be displayed for too long. Or actually, with your suggestion, we don't need a report option, if a comment/post gets low enough rating (many downvotes), the admins should be notified so they can take care of it (delete or keep or even remove downvotes by spam accounts).