On what basis is the position of an answer decided?

Question

Consider a situation where there are multiple answers on a single question. By how much do these factors weigh in when deciding the position of an answer in top to bottom order?

1. Number of up votes
2. Acceptance of an answer
3. Awarded bounty (not always the accepted answer)
4. number of downvotes
5. Size, clarity or other factors that I might not know about

Answer 1

There are three sorting options:

Active, oldest, votes. In all cases:

1. The accepted answer ranks first...
   • Unless it is by the OP of the question, in which case it's treated like any other answer.

The default is by votes, in descending order. The active and oldest sorting orders do what they say: sort by modification time (most recently modified first) and sort by creation time (oldest first).

Sorting by votes has more caveats:

2. Bounties aren't considered. Only the score of the post is.
3. Posts with equal scores are sorted randomly.
   • Unless there are enough answers to cause pagination.

Sorting by modification date also ignores bounty awards (presumably because the bounty award notice is not a numbered entry in the revision history).

Answer 2

That depends on the author of the question (for answer acceptance) or the persons looking at the answers for help, and other factors, of which would make a many page article or blog post, and ultimately cannot be ordered in any sane sense that would make sense to other users.

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Take into account number of upvotes and number of downvotes (not always visible because of rep requirements), on this prime example where an accepted question is not actually working but my answer is. The accepted answer had 27 upvotes and 5 downvotes. My answer has the +500 bounty and 82 upvotes with 0 downvotes. The key point here is that my answer came in long after the accepted answer was accepted. The issue in this case was that the accepted answer 'no longer worked' but my answer which I pulled from the 'net did work and was extremely thorough (to this day it still works). That would make my answer valid and the accepted answer invalid, but since none of us are the question author we can't change the accepted question.

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Let's take another prime example, on this question. In this case, let's assume that this is before my answer was accepted, and it's just my answer and someone else's answer.

The other answer on here does a decent job of a short and concise explanation of what's being asked. Then I come along, the maintainer of the nginx package in ubuntu, and make a long post about the answers. My answer was accepted because i'm the authoritative resource for nginx package/flavor questions in ubuntu - there is no higher authority as I'm the one doing the package maintenance. So, accepted or not, my answer could techincally be considered the answer because it comes from the highest authority.

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Normally, though, we're going to have the case of it being "Which answer works for me" vs. accepted, number of votes, bounty, etc. So it varies greatly from answer to answer, and it can't really be answered succinctly here.