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Re:How AI changed organ donation in the US by hangonhn on Wednesday September 12, 2018 @12:56PM (#17970748)
Freakonomics has a really good podcast episode on chain donation

http://freakonomics.com/podcast/make-me-a-match-a-new-freako...

But to call it an triumph of AI is stealing credit from the economists. It was an economist who came up with the idea and the field of study, market design, is fascinating, especially to those who are into startups and disruption.

Re:How AI changed organ donation in the US by majos on Wednesday September 12, 2018 @01:37PM (#17971102)
I had a similar reaction, since it's not like these matching algorithms do any "learning" (as far as I know). And you are right that the credit here goes largely to economists.

But the article does point out that we do a lot of goalpost-shifting when it comes to defining "AI", so "algorithm solving what we thought was a very human task" plausibly falls under that umbrella. I think that's the rhetorical point of using that word.

Or maybe they just figured "AI" drives clicks.

Re:How AI changed organ donation in the US by peoplewrong on Wednesday September 12, 2018 @01:50PM (#17971212)
I agree this isn't really "AI" but this project required a lot of algorithm tuning and development....

Here are some good slides.

http://www.cs.cmu.edu/~arielpro/15896s16/slides/896s16-14.pd...

The "credit" should go to the research community that worked on this. which is a mix of economists and computer scientists..........

Re:How AI changed organ donation in the US by YeGoblynQueenne on Wednesday September 12, 2018 @05:05PM (#17973315)
>> I had a similar reaction, since it's not like these matching algorithms do any "learning" (as far as I know).

Learning is not a criterion for AI/ not AI. The kind of system described (though only very vaguely) in the article is a rule-based system, possibly an expert system. These hand-crafted systems were the norm in AI up until the '90s or so and are still in widespread use in various domains (e.g. in finances, or air travel bookings etc).

In fact, machine learning took off largely as an effort to avoid having to hand-craft rulebases and elicit expert knowledge from domain experts. You can see this very clearly in decision-tree learners: these basically learn the rules that a human would be creating by hand.

It's also possible that the system described in the article is using some kind of resource allocation algorithm, like a linear programming algorithm, or some such. Those are actually optimisation algorithms, so they are easier to recognise as AI by today's standards (i.e. by the standards of the last 5 years or so of press releases by Google :).

In any case- the majority of AI, historically, has nothing to do with (machine) learning and instead focuses on reasoning in complex domains.

Re:How AI changed organ donation in the US by peoplewrong on Wednesday September 12, 2018 @05:20PM (#17973482)
> The kind of system described (though only very vaguely) in the article is a rule-based system, possibly an expert system. These hand-crafted systems were the norm in AI up until the '90s or so and are still in widespread use in various domains (e.g. in finances, or air travel bookings etc).

this is wrong at least for UNOS (united network for organ sharing)-which is the main system in the article-the current computer program used to find matches is an integer linear program. I think it is an interesting question if some kind of rule based system could replicate their ability to find the matches. I tend to think not.

https://pdfs.semanticscholar.org/0837/80a157a7f8ebfa44dce0bc...

page 16 "To our knowledge, there is no solver that would scale to the nationwide steady-state size— including the CMU solver used by UNOS. This solver is based on the work of Abraham et al. (2007), with enhancements and generalizations by Dickerson and Sandholm, and uses integer linear programming (IP) with one decision variable for each cycle no longer than L (in practice, L = 3) and constraints that state that accepted cycles are vertex disjoint. With specialized branch-andprice IP solving techniques, Abraham et al. (2007) were able to solve the (3-cycle, no chains, deterministic) problem at the projected steady-state nationwide scale of 10,000 patients"

edit: wait wait this comment could be out of date. The google scholar for this paper says 2018 but the paper says 2013??

Re:How AI changed organ donation in the US by YeGoblynQueenne on Wednesday September 12, 2018 @05:27PM (#17973552)
Cheers. Just as you were posting this I read your comment and noticed, in the link, the reference to MIP. However, it does sound like early matching systems where simply hand-crafted rule-bases encoding experts' decision-making process, so expert systems:

One night in 2000, tired of delivering the heartbreaking news to patients and their loved ones that no suitable kidney could be found, a US nephrologist named Michael Rees lugged home several crates of files and spent the next few hours scrutinizing blood, antibody, and tissue data, and comparing patient charts. The work was mentally grueling. Eventually, he realized he had no viable matches—but also, that if the pool were bigger, pairs could be made. Working with his father Alan Rees, a computer scientist, Michael Rees created a simple computer program that did the work of pairing up donors and recipients, introducing AI to the matching process.

Re:How AI changed organ donation in the US by peoplewrong on Thursday September 13, 2018 @11:16AM (#17979270)
I bet the first version of this was some kind of maximum bipartite matching. like hopcroft-kraft

but on the topic of experts check out this paper by the same research group. This is much more of an 'AI' paper that does include expert domain knowledge and learning

"FutureMatch: Combining Human Value Judgments and Machine Learning to Match in Dynamic Environments" from AAI2015

http://jpdickerson.com/pubs.html

Re:How AI changed organ donation in the US by YeGoblynQueenne on Wednesday September 12, 2018 @05:33PM (#17973605)
>> edit: wait wait this comment could be out of date. The google scholar for this paper says 2018 but the paper says 2013??

Chill! Your refs are up-to-date :)

There's two versions of the paper, one published in the Proceedings of the ACM Conference on Electronic Commerce, in 2013, the other published in 2018, in, er, Informs PubsOnline (??) in 2018. The latter appears to be an online journal- sorry if I messed up the name, I don't know the journal.

Re:How AI changed organ donation in the US by YeGoblynQueenne on Wednesday September 12, 2018 @05:14PM (#17973407)
Oh, right. I see in peoplewrong's link that the system actually uses MIP, which is to say, Mixed Integer Programming, a type of Linear Progamming:

https://www.gurobi.com/resources/getting-started/mip-basics

https://en.wikipedia.org/wiki/Integer_programming

https://en.wikipedia.org/wiki/Linear_programming

Re:How AI changed organ donation in the US by currymj on Wednesday September 12, 2018 @02:11PM (#17971436)
there's a nonzero amount of genuine AI/machine learning going on in the research end of things right now in this field.

but you're right, as is currently deployed, a better title would be "how mathematical optimization changed organ donation". or "how letting computer scientists attack a problem changed organ donation".

Re:How AI changed organ donation in the US by peoplewrong on Wednesday September 12, 2018 @01:48PM (#17971185)
mechanism design/market design is a huge part of CS that overlaps with economics. Also I am not sure how much the article emphasized this but a big part of the success of these programs is designing 'good' matchings which is computationally tricky and also requires a bunch of domain expertise. actually implementing this and understanding the complexity limitations/what type of ILP (integer linear program)/ fault tolerance etc etc... is a triumph of computer science (also econ!)