Warning:  This is very basic game theory, so if you’re expecting an exhaustive analysis, you’ve come to the wrong place.

The phenomenon we’re trying to analyze is that of “link love” between websites (primarily blogging sites).  Link love, quite simply, is when some website links to some other website.  I’m not talking about reciprocal relationships whereby both sites agree in advance to link to each other, but the random, unplanned case.

Let’s assume we have two players in this game.  Player A and Player B (like real game theorists, my creativity when it comes to naming random characters is astounding).  For purposes of our discussion, we’ll assume that both players are behaving rationally and in their own interest.  We’ll further stipulate that “in their own interest” means increasing their search rankings through engines like Google.  Clearly, there can be other things the players are interested in, but I’m writing the hypothetical, so I get to make this crap up.

Player A and Player B both manage reasonably popular websites and write content for them.

At some point, Player B happens upon Player A’s site and finds the content there of interest (Player A is writing on a related topic).

So the question is, what will Player B do?

Here’s an approximate line of reasoning:

How Player B might think of this (we’re in the mind of Player B, who is talking to himself):

1. I like the content over there on Player A’s site.  It’s good stuff.  I’m going to give her some link love and link to her.
2. In a small way, this helps Player A increase her rankings – which is a good thing for her.
3. Perhaps someday, she’ll see some traffic from my site, and reciprocate by linking back to me.
4. This will raise my search rankings.
5. But wait…when Player A already has a link from me, she is benefiting by the search ranking increase.
6. If I were Player A, would I reciprocate and link back?
7. If she did, then the value she would be getting from my inbound link would be diminished by linking back.
8. I read somewhere that Google penalizes these kinds of “back and forth” links (so it reduces the impact of the linking either party gets).
9. So, if I were Player A, and I saw this inbound link, I’d leave well enough alone.  Simply by reciprocating, I’m diminishing the value of it.
10. So, Player A won’t link back to me – it’s not on in her interest.
11. So, I’m not going to link to her, because by doing so, she is less likely to link to me than otherwise.
12. And even if I did, the best I’m going to do is come out “even”.
13. I’d rather just wait for her to find me, hope that she doesn’t go through this same line of reasoning and links to me.

Big Warning:  This is a gross, gross oversimplification.  There are lots of other variables at play – and I don’t claim to understand the details of the Google algorithm.  But, I think a mini version of the above “game” goes on all the time.  There are variations of the game (especially when there are more than on two players).  Complexities arise also when the two players are asymmetric (i.e. one is an “A-list” blogger and the other is not).