Creating a friend recommendation algorithm from social network data | Hacker News Reader

Creating a friend recommendation algorithm from social network data

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59 pointsantgoldbloom13 comments

The way people would navigate the suggestions, would in itself allow you to match up like-minded people.

But there are two types of like-mindedness - the longterm common interest and the shorterm.

By this I mean if you ask somebody to list there favourite numbers - say first 5 numbers and then matched those to other peoples choices, that would be in general static choices and would give you some common grounds of a longterm interest.

Now if you asked people to pick 5 random numbers - those that matched would be people who have a short term comminality with those who matched up in that at that point in time there intune and thinking the same.

A better example would be crowd mentality in that with the right set of instances the crowd will share a interest and act as one were if they were all isolated would they share the same reactions. That is the difference with a short term say FOTM type comminality and long-term.

It's not easy and if it was then life would be very boring as everybody would be very samish and they are not.

Also with every rule there is always an exception and the classic phrase "opposites attact" does have some weight and also goes against any form of pattern matching as it is not a hard and fast rule you can say just beacuse they are the complete opposite they will get on.

This assumes that Facebook is something like a dating site, where people are seeking others with a common interest.

But are people seeking anyone on Facebook?

I would claim that Facebook is essentially the "end of point" of a friendship. You are not going to become close to someone through Facebook, just avoid the complete lack of contact that otherwise accompanies having met someone two years ago - where short-term interests can still watch each other long-term.

If people aren't seeking new contact on Facebook, all the algorithms in the world won't help them achieve it.

I would claim that Facebook is essentially the "end of point" of a friendship.

What would the Facebook of starting-points look like? :)

Some combination of meetup.com, an events site and a dating site.

I think this is a problem Facebook only thinks it has. Or only thinks it can solve. Or only thinks most people are trying to solve.

There's every indication the US is essentially saturated by Facebook. My in-real-life friends who want to be on Facebook are already there. That's the usual ~150 that I think studies show is max nearly everyone can maintain. I also have a nearly equal number of purely Internet or Facebook or Professional friends. I'm not inclined to have less but I get the strong feeling a good portion of my friends want less, not more people to interact with online.

I wouldn't mind meeting new people. But I no reason to have more Facebook friends.

Perhaps the only way Facebook can keep its momentum going is to sponsor picnics and couples dancing across country. The only way to get aggregate more Facebook connections between people would be for people to suddenly actually have more "real life" friends.

I think these algorithms may be used behind the scene to find out interesting sources of content for a user. Not necessarily for adding new friends (although this was the context about), but maybe to select interesting news for you.

You might be right for people like you, established Facebook users. But for users who have accounts less than 2 weeks old, this makes a substantial difference.

Indeed, it will help with onloading and increasing usefulness due to network effects, etc..

I don't believe Facebook set up this contest in order to find solutions to a problem they have. The biggest clue is that the graph given to contenders was a directed graph, unlike Facebook's social graph.

It seems very likely to me they used that problem in order to find good candidates for their data-group, which is exactly what this contest was all about. Either that, or they are trying to expand the social graph of Instagram :)

I'm pretty sure that Facebook's social graph is directed since they introduced the Subscribe To feature.

> the usual ~150 that I think studies show is max nearly everyone can maintain

This is what you're thinking of:

http://en.wikipedia.org/wiki/Dunbar%27s_number

Given that the facebook graph is fairly mature I would think that this would actually be against their best interests - surely a good friend recommender is one of the things that a new entrant would need to break the market?

You still need the graph to run the recommender. This algorithm would help new users get up to speed quickly, with better results when the social graph is large; it's just another network effect.

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