I found this link aggregator that someone made for a personal project and they had an exciting idea for a sorting algorithm whose basic principle is the following:

Upvotes show you more links from other people who have upvoted that content
Downvotes show you fewer links from other people who have upvoted that content

I thought the idea was interesting and wondered if something similar could be implemented in the fediverse.

They currently don't have plans of open-sourcing their work which is fine but I think it shouldn't be too hard to try and replicate something similar here right?

They have the option to try this out in guest mode where you don't have to sign in, but it seems to be giving me relevant content after upvoting only 3 times.

There is more information on their website if you guys are interested.

Edit: Changed title to something more informative.

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[–] hissingmeerkat@sh.itjust.works 39 points 11 months ago (1 children)

No, not as simply as that. That's the basic idea of recommendation systems that were common in the 1990s. The algorithm requires a tremendous amount of dimensionality reduction to work at scale. In that simple description it would need a trillion weights to compare the preferences of a million users to a million other users. If you reduce it to some standard 100-1000ish dimensions of preference it becomes feasible, but at the low end only contains about as much information as your own choices about subscribed to or blocked communities (obviously it has a much lower barrier of entry).

There's another important aspect of learning that the simple description leaves out, which is exploration. It will quickly start showing you things you reliably like, but won't experiment with things it doesn't know you'd like or not to find out.

[–] Danterious@lemmy.dbzer0.com 4 points 11 months ago (1 children)

There’s another important aspect of learning that the simple description leaves out, which is exploration. It will quickly start showing you things you reliably like, but won’t experiment with things it doesn’t know you’d like or not to find out.

Why would this be the case? It shows you stuff that people who like similar stuff that you do like, but people have diverse interests so wouldn't it be likely that the people that like one thing like other things that you hadn't known about and that leads to a form of guided exploration?

[–] hissingmeerkat@sh.itjust.works 15 points 11 months ago (1 children)

There's two problems. The first is that those other things you might like will be rated lower than things you appear to certainly like. That's the "easy" problem and has solutions where a learning agent is forced to prefer exploring new options over sticking to preferences to some degree, but becomes difficult when you no longer know what is explored or unexplored due to some abstraction like dimension reduction or some practical limitation like a human can't explore all of Lemmy like a robot in a maze.

The second is that you might have preferences that other people who like the same things you've already indicated a taste for tend to dislike. For example there may be other people who like both Boba and Cofee but people who like one or the other tend to dislike the other. If you happen to encounter Boba first then Cofee will be predicted to be disliked based on the overall preferences of people who agree with your Boba preference.

[–] Danterious@lemmy.dbzer0.com 2 points 11 months ago (1 children)

If you happen to encounter Boba first then Cofee will be predicted to be disliked based on the overall preferences of people who agree with your Boba preference.

With this specific algorithm, I don't necessarily think that would be the case. It only shows you fewer links from people who like the links that you dislike. It doesn't show you fewer links based on what people who are like you dislike which is what it seems like you are describing.

Also, it doesn't have to be this specific algorithm that we implement but I thought the idea was unique so I thought I'd share it anyway.

It seems to be working well enough for me now so I plan to keep using it and see what it's like.

[–] hissingmeerkat@sh.itjust.works 3 points 10 months ago

Whether or not you use downvotes doesn't really matter.

If what you like is well represented by the Boba drinkers and the Boba drinkers disproportionally don't like Cofee then Cofee will be disproportionally excluded from the top of your results. Unless you explore deeper the Cofee results will be pushed to the bottom of your results. And any that happen to come to the top will have arrived there from broad appeal and will have very little contribution to thinking you like Cofee.

If you don't let the math effectively push things away that are disliked by the people who like similar things as you then everything will saturate at maximum appeal and the whole system does nothing.

[+] skullgiver@popplesburger.hilciferous.nl 22 points 10 months ago* (last edited 10 months ago) (3 children)

[deleted]

[–] statue_smudge@lemmy.world 7 points 10 months ago (1 children)

Storing it as a sparse graph should reduce the storage requirements drastically, since most edges wouldn’t exist.

[–] Danterious@lemmy.dbzer0.com 3 points 10 months ago* (last edited 10 months ago) (1 children)

you should consider moving to Facebook or Threads, maybe?

Not an option

As for the rest yeah those do seem like genuine obstacles. Partially think the reason I liked the algorithm is because it reminded me of the Web of Trust things like Scuttlebutt use to get relevant information to users but with a lower barrier to entry.

Also as I've said elsewhere it doesn't have to be this exact thing but since this is a new platform we have the chance to make algorithms that work for us and are transparent so I wanted to share examples that I thought were worthwhile.

Edit:

You’d also turn Lemmy into the strongest echo chamber you could possibly create.

PS. I don't think that's true. Big tech companies that have more advanced algorithms would probably be much better at creating echo chambers.

[–] criitz@reddthat.com 1 points 10 months ago

Instead of comparing every single individual users votes with every other one, you create clusters using data science techniques and bucket all users into those clusters, which are calculated on a nightly or weekly basis. By controlling the cluster size you can keep the number of comparisons managable, and still achieve OP's vision.

[–] fruitycoder@sh.itjust.works 16 points 10 months ago (3 children)

It might be easier to have posts be given tags and weights and have up voting and down voting change a users tags and weights and maybe have new content sorted by closeness to the users vectors space.

That way you aren't having to track every event but instead having events update the objects values.

That would be my thought at least. Though I would think it would be best that users could sliding scale the effect. As in let the user determine how "aligned" they want the posts they see to be with them.

[–] decisivelyhoodnoises@sh.itjust.works 6 points 10 months ago* (last edited 10 months ago) (1 children)

easier to have posts be given tags

If this is not being done automatically by the server by analysing the content, people will not use tags, or use irrelevant tags, or fill it with tens of tags like Instagram's early days or whatever else I cannot think of now. But I think it is not easy to work as intended

[–] fruitycoder@sh.itjust.works 1 points 10 months ago

Agreed, maybe both user tags (when we use it) but mostly automatic parameter weights. For the reason you mentioned, I'm terrible at using tags personally.

[–] Danterious@lemmy.dbzer0.com 2 points 10 months ago

Sounds interesting.

[–] fruitycoder@sh.itjust.works 2 points 10 months ago

Admittedly I'm really studying vector databases for retrieval augmented generation (RAG) AI. So it could just be my mind seeing a nail for that hammer, but it seems like vector search between a user for posts instead of a query and documents might work

[–] solrize@lemmy.world 15 points 10 months ago

Do not want. It puts everyone into their own little echo chamber. What we have is already bad enough. Just sort chronological for everyone.

[–] bluespin@lemmy.world 8 points 11 months ago

Interesting idea, but it sounds computationally expensive which could pose problems. Smaller, hardware-restricted servers would be less viable

[–] ada@lemmy.blahaj.zone 5 points 11 months ago

Now that is a fascinating idea. I really like it

[–] 4realz@lemmy.world 4 points 11 months ago

That way people can get content relevant to them. Genius.