Hi reddit,

We are MIT professor Hal Ableson, author (with Gerald Sussman) of the popular computer science textbook Structure and Interpretation of Computer Programs, founding director of Creative Commons, Public Knowledge, and the Free Software Foundation, and creator of the first "turtle graphics" system in 1969 that is featured in the Algorithm Auction – joined by Chris Coyne (proof!), co-creator of OkCupid and Keybase, and, a long time ago, SparkNotes. The OkCupid Compatibility Calculation, an algorithm that has changed millions of lives, is also part of the Algorithm Auction.

The Algorithm Auction, created by Ruse Laboratories, is the world’s first auction celebrating the aesthetic beauty and unique influence of pure code at the Cooper Hewitt Smithsonian Design Museum. You can learn more about it here.

THANKS ALL! This was a lot of fun. -Chris

Comments: 105 • Responses: 13  • Date: 

beernerd45 karma

Chris, did it ever occur to you that the OkCupid Compatibility Calculation would also be useful for helping aspiring superheros find their arch-nemesis?

malgorithms69 karma

Yes, that's specifically what we made enemy percentages for.

beernerd7 karma

I knew it! When they remake The Tick, I hope they address that.

How does it feel knowing you have brought so many people together with the power of math?

malgorithms9 karma

Beyond a certain scale it is hard to appreciate. But I have a number of close friends and family who are in excellent relationships because of OkCupid. That's what feels best.

Antagonist_3 karma

Could you detail how the Friend and Enemy percentages are calculated? The FAAAAQ tells how Match works, but not the others.

There's um, lots of theories. https://www.quora.com/How-does-OkCupid-calculate-the-friend-and-enemy-percentages https://www.okcupid.com/help/match-percentages

malgorithms7 karma

Raw enemy percentage is (1-raw match percentage). Your raw match and raw enemy add up to 100%.

That said, the way confidence adjustments work has gotten sensitive to the game-ability of questions. It used to be enemy % = raw enemy % - conf adj., and match % = raw match % - conf adj. It's no longer that simple on the confidence adjustment side. You can think of your mach percentage now as something approximating the odds someone would score as well as they did with you in raw score, given the questions in your intersection.

So it used to be that as your question intersection approached infinity, your M+E approached 100%.

(Disclaimer: I no longer work at OkC, and they may have changed something in the last couple years, too.)

None of that includes external data (messaging patterns, photos, etc.). Match score is/was strictly a function of your answers, their answers, and confidence adjustments based on aggregate question stats.

Friend % is some measure of whether you tend to be attracted/repulsed by the same things. Not whether you are the same. When I last looked, it was a weighted average of those agreements, weighted by your stated importances. Again with some confidence adjustment that shrank the more (good) q's in common.

Edit: raw match + raw enemy = 100% no matter what.

sweetlittledomme15 karma

Hello Chris,

You probably don’t remember me, but I sent you a message via Twitter about 9 months ago telling you about how I met my husband, a 99% match, on OkCupid and how we got married in Las Vegas exactly a month after meeting in Montreal. He’s a Canadian, I’m an American, and we’re living in Toronto now while he’s working in television and I’m a phone sex dominatrix. We’re still happily married and keep discovering every day how crazy life can be living with someone who is almost your mirror image personality and interest-wise. You responded to congratulate us and gave me Christian’s email address so I could contact him about an idea I had.

At the time, I wanted to create a short little film about how my husband and I met and how uniquely OkCupidian the whole experience was. Since then, I actually fleshed the idea out a bit more and would like to make a documentary about OkCupid. The documentary will focus on crazy/funny OkCupid stories (like the guy who found his mom and she was a 95% match), the OkC subculture in large cities (especially NYC, where almost everyone I knew was on there), and on the people who have been on the site for many, MANY years (like myself).

Is there any way that you would consider being interviewed for it?

Thanks for reading!

malgorithms11 karma

Congrats, again! I would consider it if you send me the details. (My email address is pretty easy to find.)

carterac15 karma

Chris, what is one of the craziest stories from your OKCupid days that you can share publicly?

malgorithms90 karma

The hardest part of this question is knowing where the line is. There are so many things I can't say.

One easy example: at OkCupid, we spent a lot of time having fun, playing around with the site's content. There's always been an essay question on OkCupid: "The Six Things I Could Never Do Without..." This was a poke a Nerve, which at the time was a popular dating site. They had a similar question, but about 5 things.

Well, one day someone jokingly changed it to say "Things I think about while masturbating..." on 1 in N pageloads. (I think N was 100 or 1000.) So every once in a while you'd see that heading followed by "Hall & Oates" or "my computer" or "my dog, Tilly."

I had to take it down when a guy in a divorce proceeding had a screenshot of it presented to a judge with "my kids" underneath it, by his wife. I had to provide a letter to the judge explaining the whole thing.

Beakless5 karma

How many distinct personality 'types' do you think there are if any at all?

malgorithms43 karma

I think people can be pretty clearly partitioned into ~7 billion personality types.

ExtraAndroid5 karma

How do you think the future is going to be different given that so many of our decisions are being made now by computer algorithms?

halatmitdotedu7 karma

The danger with leaving decisions to computer algorithms is that the algorithms are too often "black boxes", largely because the software is proprietary. People don't have the opportunity to examine them and understand why they produce the results they do. This is already a worrisome trend, and it is increasing. Transparency is a good thing, and we are losing it because of proprietary software.

malgorithms3 karma

This phenomenon Hal mentions is going to continue to expand for a variety of reasons: (1) there's more data than ever, and consumer products are designed to filter information for us, a feature we demand (how is it filtered?); (2) machine learning is increasingly becoming a part of that decision-making process, and even the developers are losing a full understanding of how their software "decides"; (3) the mobile platforms we've switched to are providing us apps which are typically run away from our own devices, meaning the software we run is dynamic and changing all the time. The block boxes are evolving. Transparency is approaching zero.

rlovesbooks2 karma

Hi guys! Met my husband on OkCupid, so thanks! January was our 4 year dataversary and on May 17th we'll have been married 2 years. Question 1) how many partners have you guys met online? Any using your ow n algorithm? Question 2) since we're a success story, when do we get our free t-shirts? (This has been a joke between us since our second date)

malgorithms2 karma

Congrats! (1) none, all of us who founded OkC were dating our SO's when the project launched. (2) Love AND t-shirts? New business idea...

Frajer2 karma

Chris - how do you feel about people using spark notes instead of reading the book?

malgorithms8 karma

Mostly not great. But it depends on the book. Also compulsory reading can take the love away.

Btw, my father was a high school English teacher and he said he never truly appreciated Moby Dick until he used a study guide alongside it. I felt the same way about Lolita.

Aside: I used to get the digs in by telling him I caused more reading avoidance per day than he could get his students to do in a lifetime.

ioscoding2 karma

Which one your accomplishments are you most proud of? Why?

malgorithms3 karma

Work-wise, so far it's OkCupid. We have some big plans for Keybase, and we'll be launching something later this year I'll be very proud of.

dragonfly19932 karma

what inspires you?

malgorithms4 karma

I personally like to work on things that are a combination of (1) creative, and (2) likely to make other people's lives better. The latter is a silicon valley cliche, but it has become a guiding requirement for me and my business partners from OkCupid, SparkNotes, and Keybase. (I've worked with the same guys since college.) We're in the fortunate position now to work on whatever software we want, and we're unlikely to pursue something just because it's a great business. It has to be creatively challenging and rewarding, and it has to be, in our opinion, good for the world.

In my free time, I like to make software that generates art, and I've done a number of projects, most of them private. One thing is CFDG, a language for generating art. (It's nice to have Hal on here, because turtle graphics was an inspiration for that.)

The algorithmic auction is particularly appealing to me because (1) it benefits a museum, and (2) it's a wonderful combination of creative programming. I feel lucky to be included.

Antagonist_1 karma

For Keybase, are you trying to make encryption and private communications easier for non-technical people to use?

Keybase is great for techies to have a unified easy to use keystore, but how can we make verifiable open encryption easy?

malgorithms1 karma

Keybase, as it is right now, isn't so useful for non-programmers. It's a directory, and I believe it's the right kind of directory, but it doesn't answer a number of questions.

We're working on something now -- I don't want to let the cat out of the bag early, but these are all needed for secure communications:

(1) correctly solving the identity problem (no key fingerprints, key signing parties, etc.) (2) good cross-client software (3) per device keys, not a private key you need to move around.

Also, with a successful PKI the goal isn't just privacy, it's authenticity / verification. It's very hard right now to collaborate with safety.

sam___handwich1 karma

How is your band Bishop-Allen working out?

malgorithms4 karma

You're thinking of Christian Rudder, my co-founder at OkCupid.

I am proud to be in the opening line in one of their songs, however: