What’s Wrong With the OkCupid Algorithm for Matching People?

My blog assistant sent me this link about the science behind OkCupid’s algorithm.

I watched the seven minute video and while I found it entertaining, I saw two big flaws in the way OkCupid purports to match you based on compatibility:

1) OkCupid has three pillars of their algorithm – what you think, what you want your partner to think, and how important it is to you.

This all makes sense in theory, but it falls apart in practice for this reason: people don’t know what’s good for them. Really. If they did, I would be out of a job.

Simply put: what you’re attracted to and who you’re compatible with are two very different people. Most people – myself included – are wildly attracted to the opposite sex versions of themselves. Do you like skiing? Then HE better like skiing!? You’re charismatic? HE better be charismatic! You make a lot of money? HE better make a lot of money! Such commonalities may cause you to be more attracted to someone, but none of these things are good predictors of true compatibility.

That second pillar of the OkCupid algorithm doesn’t say much of anything – it only goes to show how narcissistic you are in searching for someone who is just like you.

As such, that second pillar of the OkCupid algorithm doesn’t say much of anything – it only goes to show how narcissistic you are in searching for someone who is just like you. For this algorithm to work, people would have to be a LOT more self-aware about compatibility – and they’re not.

Because you could find a neat-freak who likes being the center of attention, but if he doesn’t believe in marriage, or doesn’t make a livable wage, or doesn’t believe in sharing household duties, it doesn’t matter.

2) The way OkCupid weights importance is seriously out of whack (see 4:43 in the video).

Irrelevant = 0
A little important = 1
Somewhat important = 10
Very important = 50
Mandatory = 250

A little important is BARELY scored higher than irrelevant. Mandatory is TWENTY FIVE times more important than “somewhat important”. I’m positive some very bright people put some thought into this and decided on this scale, however I don’t know how “somewhat important” can be ten times more valuable than “a little important”, while “very important” is only five times more valuable than “somewhat important”. It’s all very arbitrary and inconsistent, if you ask me.

Frankly, I think eHarmony’s compatibility testing is probably smarter and more relationship-based than OkCupid. The problem, of course, is that eHarmony took all the fun out of their questions and removed attraction from the equation. So you have OkCupid, which is fluffy compatibility pseudoscience based on physical attraction and common interests (as if mutual love of horror films has anything to do with anything) and eHarmony, which is undoubtedly deeper, but ignores the base human impulse to look up attractive faces. Most people I know are using OkCupid because it’s more fun, not because it produces better matches.

Your thoughts, below, are appreciated.

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  1. 31
    Peter 61

    @Kathleen.  Younger men are looking for an easy sexual conquest.

  2. 32

    Peter 61 
    Its been my experience that men of all ages are interested in an easy sexual conquest  😉
       I was just curious why this was happening on only one site when essentially using the same profile as on Match 
    Karmic #31
    True !  I did go on a date with a 35 year old who was particularly interesting and mature. During the evening he got carded LOL!! 

  3. 33

    I was on OKC for three months in 2011. At the end of three months, I had a few good friends (that I still stay in touch with) and a bf. I was over 90% compatible with all of them; 95% compatible with the bf. (The remaining 5% finally got us, and he’s now the ex-bf, but we had a very good two years together.) So in summary, OKC’s matching system worked great for me, and I plan to rely on it again when I go back to dating in a few months. That said, my mindset is different from most women’s (and some men’s) in that I’m more logical than people usually are, and rely on chemistry a lot less than most people (including my ex) do. Maybe that was why the OKC matching system worked for me, while it may not work for someone else who’s wired differently. Personally I have no complaints about it.
    Want to add, I used the matching system, not so much to find my 99%-match soul mate, as to weed out the bad matches. I’ve tried talking to a few people that were low matches, looked at people’s answers to see what had caused the low match, and without fail, all of those men were completely incompatible with me. So it got to the point where, if I had a message in my inbox from a 30% match, I used to just save us both valuable time and ignore the message.

  4. 34

    Apologize for double post, I missed Kathleen’s #29 on my first try. Kathleen, I had the same experience on both OKC and Match. I was 44 and on OKC I’d get flooded with messages from guys in their 20s. Once a guy messaged me that was the exact same age as my son, ewww no! Why was that child even on a dating site? I still preferred OKC to match, because I was at least being contacted by a lot of people from my age group. Whereas on Match, no one under 50 would even consider me. I’ve also had two 67-year-olds contact me on Match and then get bent out of shape when I said no. Sorry Sir, if you are old enough to be my father, you’re too old to be my boyfriend. I’ve gotten two or three good dates from Match, but I won’t be going there again, because I just don’t think I got a good enough return for the price. Maybe it had something to do with the fact that, in my location at least, OKC attracted the better educated, more intellectual crowd, while on Match most people actually listed watching sports and grilling as their only interests. Don’t know if Match still has this, but two years ago, there was a “last book you read” question on their profile. The answers people gave to that question, would’ve been enough for anyone to lose their faith in humanity.
    To your question Kathleen, I think it’s the site’s demographics rather than your profile. I see no way to deal with it other than the delete key.

  5. 35
    Newly Married Woman

    On POF I got 1 lifelong friend and 1 long term relationship. On eHarmony I got lots of 1-3 dates and one wannabe friend/skulk-around-hoping-for-change-in-the-weather whose phone calls I had to stop returning after several months because his values were so off-center from mine (deep compatibility??!!).

    The first day on OKC I got an email from Mr. Wonderful.  He made me his bride 52 weeks later.

    Results speak for themselves, so you can call me and my beloved bridegroom big fans of OKC. The mileage of others may vary.

    As for analyzing? Although the caliber of men on eH seemed to be uniformly higher than the great unwashed sea of humanity on POF, the stultifying rigamarole involved in getting past the barriers to the actual person seem to A) stack the clientele full of women.  B) suck the life out of both parties before they ever meet.

    I know A is true at least for my area because I learned I was paying a much higher rate than the men were. A reverse of the “Ladies Night” pricing used by bars. I know B is true because I lived it.

    OKC was a wonderful hybrid of filtering and reasonably swift access.
    What I especially appreciated about it was the questions because some guy could look really good on his main profile but in the questions reveal some definitely not for me sexual peccadillo or other personality trait.
    I got plenty of response on OKC but my beloved really stood out and I closed out my profile in just a few weeks. During that time, I did find it to be the best of the services I had tried. Is the OKC algorithm perfect? Why should it be? Nothing else in life is.  Ultimately people do the choosing and rightly so. eH seems to think they can take the humans out of the equation. Results: blech.

    Lest Evan cast a chary eye at how quickly we moved from 1st date to “I do,” let me say that everyone who meets my now-husband can see how top notch he is. He seems to think highly of me, as well. We were 49 and 51 when we met, plenty old enough to know our way around. We are very happy. Smartest thing I ever did in my life was say “yes” to him. Thanks, OKCupid!

  6. 36

    Like most I was on match.com, eHarmony and other paying dating sites. Finally about a month ago I started using Okcupid. 
    I like Okcupid because I find that people are more honest and blunt. Yes you find a lot of married man in open relationships and a lot of “I am not looking for love right now” but at least they tell you and are honest, maybe not everyone but most. I find that because is free, people don’t care to lose the interest of some. Also I love the questions because it does tell me a lot about the person. I think I would ask some of those questions to a potential match off line. People lie, exaggerate and omit, yes, in all sites but my personal experience in Okcupid is that 90% of the people who are different from or have very different believe system or moral views me A.K.A weirdos are open about it. I really appreciate it because I get the chance to “skip” as with particularly match.com they hide it and you find out later. 

  7. 37

    @Newly Married Woman #36 “The first day on OKC I got an email from Mr. Wonderful.  He made me his bride 52 weeks later.”
    That’s great that you had that kind of luck on OkC but really that’s like saying “I bought a lottery ticket at the gas station on main st and won a million dollars so in my opinion that’s a great gas station!” If your hubby would’ve emailed you on POF or Match you would of probably still emailed him back and the outcome would’ve most likely been the same. It had little to do with OkC’s  algorithm matching.
    All I’m saying is most people go and sign up for where they see the most available options in the area in which they live and the age range they’re looking for. In my area that’s Match. In my experience (18 yrs of online dating) people email well written profiles with quality attractive photo’s and the statistics that they’re looking for not compatibility and goofy algorithm percentages etc…. That includes women….lol probably even more so. 😉

  8. 38

    I think luck plays a factor in when people find the right person. So many people do all the right things and never find the right relationship. Post #36 is very indicative that luck plays a role. It’s such a myth to think hard work is what leads to success. Go and read Malcolm Gladwell’s book on Success entitled: Outliers.

  9. 39

    @ Paula, I am not sure of what point your trying to make, as my understanding of Outliers is that the people the author profiled put in a lot of work (i.e 10,000 hours) to be successful and when opportunity struke they were then prepared. I do believe, the main idea of the book was that hard work + luck = success and that you needed both.
    I do agree that a certain amount of serendipity is an ingredient in most relationships where the SOs give feedback that they are happy, but with out insight, or relationship skill, it’s highly doubtful one could be soley successful on luck alone, in my humble opinion.
    The specifics in dating websites, seems to be a minor detail, because if your dating and available, your going to meet someone worth while as opposed to going to work and home and back to work again.
    Though watching the ID channel this past weekend has me feeling a little leery of Match. Lol.

  10. 40
    Newly Married Woman

    @JB #38,  I do understand your point, I really do.
    But I believe the OKC algorithm does have value because it put the two of us in the same cyber-neighborhood at the earliest opportunity and it did so with some justification, not randomly (POF) and not with onerous restrictions or dubious calculations (eH).
    I believe the barriers in eH tie up too many of the dater’s resources: time, attention, emotional energy, false sense of investment in the process. The fact that I did not get a single relationship or even friend out of eH tells me something is not so perfect about their idea of who is good for me.
    This makes me wonder if eH would even have ever put me in my husband’s batch or he in mine. 
    I did get several successful outcomes out of POF and, of course, a wonderful marriage out of OKC.
    @Paula 39,
    I agree luck does play a part.  Not everyone will find love on OKC, but for me and my lovely guy, its system proved valuable and effective and better than random chance. YMMV.
    P.S.(I forgot about a couple folks, I got not one but three relationships out of POF as well as the one friend.)

  11. 41

    Not sure if this was addressed, since I didn’t read through all the comments, but I find a number of other flaws in the algorithm.  Say one person answers 6 questions and another person answers 600 questions, Okcupid will still show a compatibility score for both prospects.  Yet how is it possible with so little information for the tally to be accurate in showing compatibility?  And what if one person answers a series of banal questions such a favorite ice cream flavor and another person answers questions citing core values, again, their compatibility percentage will still be visible.  A date I was on suggested Okcupid also cite a reliability percentage but I think a better solution would be to not have a compatibility score visible unless both prospects answer a variety of questions across a spectrum.  The spectrum being questions having to do with personality, values, interests, etc.  And questions such as, do you want to have children should carry more weight (scored differently) than questions lower in importance which are not necessarily deal breakers. 

  12. 42

    I don’t know how scientific it is, but I met my boyfriend on OKCupid and he’s about as perfect for me as he can get.  lol  Maybe I just got lucky?

  13. 43

    I found the questions on OKC were funny and helped me learn something about each individual that I was curious about. I’m newly widowed (married for 22 years). So the whole online dating world was very new to me. My son recommended the site to me because he met his current girlfriend on the site too. They just celebrated nine months together.
    I set up my OKC account on a Thursday and shut it down by Saturday because I had found a great match in a man that believed and wanted the same things as I do.
    The nice thing about the account is that I was immediately contacted by a dozen men of all of different nationalities and ages. I’m bi-racial (Filipino/black). I’m a BBW which didn’t stop any of them from contacting me. Whatever I wrote must of been good because of the prospects that contacted me. They were all pretty much serious inquiries. I weeded through them and found the one that I am currently talking to now.
    I’m now in a committed long distance relationship and am very satisfied with the direction our relationship is going. We take each day in stride. He calls me every morning and evening. We constantly text. We talk about our future together. I’m very excited to see the hope and joy that this new man brings to my life and now to my future.
    If I hadn’t had such good luck my first time around looking for wonderful man, I would of seriously considered hiring EMK. But the information provided on his site and the emails that I’ve received are invaluable and are helpful to me in my current relationship. I will continue to read his posts and the insightful comments provided by those who post too.

  14. 44

    With online dating, people have the experience of meeting someone in person after the online ritual of viewing profiles, emailing, calling, and fantasizing about the profile/photo.
    I went to  a Match stir event that turned this experience on its head. I talked to several women throughout the night, and when I came home to view their profiles, I was stunned to find out they were nothing like their profiles. They were much more interesting and attractive in person than their profiles.
    There were also men there that were the most socially awkward people you could meet, but when I viewed their profile, they portrayed themselves as the life of the party!
    I thought “how could this be?”. Is online dating that fundamentally flawed as far as gauging chemistry, attraction, and how a person really appeals to you?
    My take away from this event is that all of this talk about online attraction and algorithms is really moot when you comes to meeting someone. In fact, sifting through profiles is such a flawed way to find a mate because we’re weeding out people who we could be attracted to in real life . . and spending countless hours, days, and weeks emailing people to only find out when we meet them in person after 5 secs that there isn’t a mutual attraction there.

    1. 44.1

      I have spent about a year on OKC both in the US and briefly in Europe. My experience has been identical so I will lump them together.  We may argue about the weighting of the match questions (as EMK does) but I found them to be workable.  However, only from a certain number of questions answered on up.  I answered a total of just under 2000 questions; mostly reply to questions answered by profiles I was interested in (sometimes just generally curious).  Unless the answers come solely from one topic, at around 100 jointly answered questions they become solid. From 200 jointly answered questions, they are 99% stable.  I matched my own ratings against those of two former GFs and one regular friend found them remarkably accurate.  There are outliers but not so many.  I still think OKC is no better than any other site because in m experience, a good match score means nothing.  Even a 96 match, 54 friend, 03 enemy match will not gain you even a reply, much less a date on their own.  As it is everywhere else, it comes down to only two factors: Picture and age. I have received mails from women with a 51 match, 40 friend, 35 enemy match and similar because, I assume, they found me attractive, but being 42 (or over 40) makes you invisible to most every women young than 36 regardless.  Lastly, as it is written elsewhere, it is a numbers game.  There’s truth to the ‘having to kiss a lot of frogs to meet your prince’ but in the day and age of online dating, where the boutique mentality prevails and the idea that perfection is attainable and waits likely just around the corner, women are even less likely to kiss any frog or even have coffee with him lest she sees “potential”.  In the picture. And the age.  🙂 

  15. 45

    Im an active Okcupid user since April 2013 and i still havent found my match. Sometimes the site suggest me people as “matches” and when i look into their answers, i dont see how we would get along, some of these guys are even assholes who dont know how to treat a women, judging for their answers to the questions so i keep using the site and i will keep using it but now i wouldnt bother with the match, i would go right to their essay and then their answers to the questions, thats only how i would know if he a potencial match, i dont care that much anymore if we have mutual interests, just that he is mature, fun and knows how to treat a lady.

  16. 46

    OKCupid provides a lot more information about people than any other website — thousands of multiple choice questions, created by users, that can also be commented on.
    The questions cover every conceivable thing that could be asked about.  To the extent that people answer them, you can figure out a lot about where they’re coming from.
    What more could you reasonably ask for (?) How well you use it is up to you.
    It’s also multi-leveled — since the questions are created by users,  there are subtleties and nuances built into some of them (if you can tune into that).
    For example: there’s a question (that almost everyone answers) about which is bigger, the Earth or the Sun.  What would you answer (?)

  17. 47

    I just started with the online dating world this past weekend and OKCupid’s software chastised me for marking so many things irrelevant.  So I really tried to have a preference about a guy’s answers to these inane details and then I had a useful revelation.  I’d think about the last two men I fell in love with and notice that we rarely had these details in common.  What made those relationships work was both men had their own interests and were totally secure with my running off to do my thing with other people, so I got to learn some new stuff from them, and we had lots to talk about when we were together.   And then when I bumped into this site, one of the first posts I read was how women are attracted to men who combine passion and competence, so now I’m reading lots of the blog ’cause EMK’s insights ring true.

  18. 48

    OKCUPID = OKSTUPID! Ive been on and off this site for over a year and have NOT gone out with one decent guy….They have all been incompatible! I like POF better! The people on this site are NOT relationship minded and have given out my phone number to some and they don’t even call lol….Not looking for a pen pal thx! I think these guys on here are lazy avoiders that give these sites a bad name…the just wanna hit it and quit it…I actually deactivated my account a week ago cuz i got so frustrated.

    1. 48.1
      Karmic Equation

      Just like IRL, there are good guys and bad guys on dating sites.
      You have to exercise good judgment in discerning one from the other.
      That said, recently, one guy seemed really cool. We exchanged #s. His texts started out ok. Then he got a little weird, so I had to block him. First one from OKC. I had that happen with one guy  on POF.
      I’ve probably corresponded with well over 100 men and had first dates with a good 30 of them. I’ve always treated dating as a fun night out making a new friend and flirting if he’s cute and being a little more serious if he’s not so cute. 2nd dates almost always happen with the cute ones, whereas it doesn’t with the ones with whom I’m less than flirty. I just can’t bring myself to flirt with someone who isn’t cute to me.
      If you’re putting pressure on yourself to find “the one” on each date, that’s when you’re going to get frustrated.
      I look upon each date as honing my flirting and communication skills. It’s a lot of fun to get guys to talk about themselves so you can get a better sense of who they are and what interests them. And then you figure out if that stuff is compatible or not with your own interests.

  19. 49

    My husband and I met on OK cupid. What does that say about us? I guess according to your logic we are both “narcissistic”.

    1. 49.1
      Evan Marc Katz

      Just because OkCupid’s algorithm measures how much “alike” people are based on silly common interests (a method of choosing a partner which I termed narcissistic) does NOT mean that two people who both like running are inherently narcissistic. If you conflate my critique of OkCupid’s matching algorithm with a critique your own relationship, well, let’s just say it would be you who is failing the logic test.

  20. 50

    Whoa, I found this video by googling “What’s wrong with OKCupid’s matching algorithm”, an article I wrote a few years ago that got on Hacker News. Seems like the video makes the exact same points that I made there, with no credit!
    There’s nothing wrong with the log scale (1,5,25,…) as this gives the user order-of-magnitude control rather than overly fine-grained control.

  21. 51

    I can’t believe no one pointed out the most obvious flaw in EMK’s argument on point 2. The difference between assigning 1 for a little important and 0 for irrelevant is not small, it is infinite. Multiplying by 0 means it will not be counted at all, which is what you want. 

    As others pointed out: no, people do not know what they want, but you can use the questions to filter (for drug use and smoking for example). This does not have to become an exercise in narcissism at all, since you can choose the answer they should provide. So if you want to date someone who is opposite to you, you can choose to do so.

    So although EMK raises some valid points here and there, I really think he should rewrite this article, as he clearly did not understand the okc video that well. No offense. 😉

  22. 52

    The problem with okcupid and their “algorithm” is that the okcupid system does not know attraction nor does it calculate it into the search. Like for example I saw a person on there who was very attractive like one of the most attractive people I have ever seen in my life but our match %? A whooping 19%. Our enemy %? Close to 80%. So here I am with someone very attractive who I am basically non compatible with well not very much anyways. Then there was the time I saw someone as close to 95% match to me but when I reviewed their pictures I found I was not attracted to them at all. What I want is for okcupid to give you someone with a high match % who you can feel attracted to when you see their pictures. But I understand that would be virtually impossible to do. I also wish they had a way to filter out results so that they only show people that have more than a certain match % so like say I could select it so that anyone under 75% doesn’t show up in my searches or something. I also put on my profile I am seeking someone 20- 38 (I’m 26) but I keep getting people in their teens and people above 38 mixed with my searches you would think their system would know based on the info you selected on your profile. But it is what it is I guess.

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