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Using Facebook Data, Algorithm Predicts Personality Better Than Friends

Posted by Soulskill on from the worst-scifi-plot-ever dept.

sciencehabit writes: A new study of Facebook data shows that machines are now better at sussing out our true personalities than our friends. One of the standard methods for assessing personality is to analyze people's answers to a 100-item questionnaire with a statistical technique called factor analysis. There are five main factors that divide people by personality—openness, conscientiousness, extraversion, agreeableness, and neuroticism—which is why personality researchers call this test the Big Five. People can accurately predict how their friends will answer the Big Five questions. ... Compared with humans predicting their friends' personalities by filling out the Big Five questionnaire, the computer's prediction based on Facebook likes was almost 15% more accurate on average, the team reports online today in PNAS (abstract). Only people's spouses were better than the computer at judging personality.

80 comments

  1. Uhm... by Anonymous Coward · · Score: 1, Insightful

    Haven't they used the same data to both build and test the model? That's Methodology 101 fail right there.

    1. Re:Uhm... by Anonymous Coward · · Score: 1

      Yup, and they take Facebook Friend == friend. Cambridge, really? How embarrassing,

    2. Re:Uhm... by Anonymous Coward · · Score: 1

      "A 10-fold cross-validation is applied to avoid overfitting: the sample is randomly divided into 10 equal-sized subsets; 9 subsets are used to train the model (step 1), which is then applied to the remaining subset to predict the personality score (step 2). This procedure is repeated 10 times to predict personality for the entire sample."

    3. Re:Uhm... by radarskiy · · Score: 5, Informative

      Haven't you failed to read the article before claiming that it is wrong?

      For those playing along at home, Fig.1 from the actual article explicitly refutes the AC's claim.

    4. Re:Uhm... by Anonymous Coward · · Score: 0

      Haven't read the paper, but often people will use cross-val during development and tune parameters/methods against it then report the results, so while test data wasn't used directly to build the model, it was used to choose a good class of models. I see this way too often (source: PhD candidate in a related field)

    5. Re:Uhm... by ch0knuti · · Score: 0

      bad mod. Posting to undo. sorry

  2. 2015: Still using Facebook by kheldan · · Score: 2, Insightful

    Why? Why, with everything that everyone knows about Facebook, all the privacy violations, all the obvious signs that they really don't give a rat's ass about the users, just the money that users' data can earn them, would anyone still be using Facebook? Is it willful ignorance? Or is it deep denial? Now, we find out: Facebook can and is being used to profile people. Come on, is this what you all really want?

    Disregard Facebook. Take your life back.

    --
    Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
    1. Re:2015: Still using Facebook by PRMan · · Score: 4, Informative

      And yet, I got dirty looks in church on Sunday because I didn't know somebody was seriously ill for a month with pneumonia. Apparently, everybody (but me) has been talking about it on Facebook and if I don't know I'm the bad guy.

      --
      Peter predicted that you would "deliberately forget" creation 2000 years ago...
    2. Re:2015: Still using Facebook by Sowelu · · Score: 1

      What's the difference, data-mining wise, between having a Facebook account and willingly using your real name all over the place online? People are perfectly happy to do the latter. I don't see why those people would care about the former. (I guess there's tracking through facebook buttons all over the place, so maybe suppose that people have solid blockers for that.)

    3. Re:2015: Still using Facebook by Anonymous Coward · · Score: 1

      But you didn't give somebody pneumonia! God is the bad guy here. Illness is God's will.

    4. Re:2015: Still using Facebook by mythosaz · · Score: 3, Insightful

      Why are people still using Facebook? Because other people are, and they use it as their medium to schedule events and coordinate activities.

      90% of my Facebook activity is devoted to participation in a handful of secret/private groups, and the other 10% is responding to event invites -- some of which are "go, no-go," others are FCFS based on responses to the invites.

      Also, I mostly DNGAF about Facebook (or Google, or whomever) knowing what flavor potato chip I prefer because I used my club card at the store. Google gave me $15.98 on their Opinion Rewards platform for knowing even MORE about me. Whee!

    5. Re:2015: Still using Facebook by Anonymous Coward · · Score: 0

      For the most part, people don't seem to be bothered by profiling and such. After all, your credit card does basically the same thing with purchase data: Profile you based on purchases and sell the marketing information elsewhere. Frankly, I don't think it makes much difference in any practical sense. Everyone's free to avoid Facebook (or any other website) if they choose to, and people that choose to participate are free to filter the things that they're willing to blare out to the world.

      I don't really understand why people enjoy "checking in" at specific locations, posting their life histories, etc, but I've never heard of a concrete negative consequence that I didn't think the person deserved, just doom and gloom about nebulous privacy concerns.

    6. Re:2015: Still using Facebook by rtb61 · · Score: 1

      Once it became necessary to manage your facebook profile so that you would appear like what you needed to appear like, facebook became pretty much worthless. Only foolish people don't carefully manage their profile, only foolish people actually use it for personal interaction because not only are you giving your privacy away but you are also giving away the privacy of everyone else you communicate with via that medium. Reality is you might as well call facebook - liebook because that is what it more accurately is, an illusion and relying upon it's data having any real value is pretty silly.

      --
      Chaos - everything, everywhere, everywhen
    7. Re:2015: Still using Facebook by kheldan · · Score: 1

      So you're willing to sell off your privacy for a few bucks? That's what you're doing if you didn't realize it. Same goes for any 'rewards club' type cards at retailers: You're giving them permission to gather personally identifiable data on you, for a few measly bucks. How does it feel knowing that there are complete strangers out there that think they know you because of the data they collect on you about purchasing habits? How will you feel about it when someone gets it wrong?

      --
      Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
    8. Re:2015: Still using Facebook by Shakrai · · Score: 2

      Why? Why, with everything that everyone knows about Facebook, all the privacy violations, all the obvious signs that they really don't give a rat's ass about the users, just the money that users' data can earn them, would anyone still be using Facebook?

      Because social networking is > than what which preceded it and Facebook has a critical mass of users that makes the alternatives (G+) pale in comparison? I have friends on five different continents. Is there an easier way to remain in contact with them? To stay abreast of the developments in their lives and to keep them current on mine? Additionally, I have friends in countries where texting isn't included in their base phone plans, so they all invariably use FB Messenger for communications that Americans would conduct over SMS. My choice is to use Facebook or to wall myself off from these people. My irritation with Facebook's nonsense is not high enough to choose the latter. Besides, FB only knows that which I choose to share; if you choose to share every single trip to the grocery store and every single sexual partner they're going to build quite the profile on you. If you're a bit more selective then they won't have as much information. Common sense applies here people.

      And I'll smack the first person that responds with "just have them e-mail you"; there's a reason why social networking displaced e-mail and anyone who is going to give that glib answer should consider how they would have responded to "just have them write you" when e-mail was the "new thing."

      --
      I want peace on earth and goodwill toward man.
      We are the United States Government! We don't do that sort of thing.
    9. Re:2015: Still using Facebook by Anonymous Coward · · Score: 0

      Why? Why, with everything that everyone knows about Facebook, all the privacy violations, all the obvious signs that they really don't give a rat's ass about the users, just the money that users' data can earn them, would anyone still be using Facebook?.

      People are still using Facebook because they are stupid.

      People are still asking why people are using Facebook because they are stupid.

      Got it ? Facebook users are stupid and you are too.

    10. Re:2015: Still using Facebook by Anonymous Coward · · Score: 0

      Yes...and when I choose not to, I will stop. That's my choice.

      And frankly, i don't care what strangers think they might know about me based on purchasing habits. Do you worry what strangers think they know about you? Why? And when they get it wrong? i certainly don't care. I'll ignore it or, if someone is talking to me, I'll tell them they're wrong. I don't really understand your problems.

    11. Re:2015: Still using Facebook by khellendros1984 · · Score: 1

      So you're willing to sell off your privacy for a few bucks?

      Not under those terms, which is why I don't use store-specific cards (since it's already bad enough that credit processors want to track me). If there were a pay service that could replace FB in all aspects, minus ads and data-gathering, I'd be more than interested to look at it.

      How does it feel knowing that there are complete strangers out there that think they know you because of the data they collect on you about purchasing habits?

      Honestly? It doesn't bother me. Similar to "How does it feel [...] that think they know you because of your pseudonynmous posts on Slashdot?" I don't do anything important on Facebook, similar to how I don't do anything important on Slashdot. Sometimes, I make posts that don't reflect my feelings, just for a change in pace. Facebook wants to see my false information? Meh.

      How will you feel about it when someone gets it wrong?

      Amused, so far. FB has been trying to guess where I live for years. I don't think that it's ever guessed the right city, and it guesses the right county only occasionally. More commonly, it picks a state across the country where it knows I have a lot of friends, or in another country. I commonly look up products that friends are interested in, but that I don't care about. I mark random ads as offensive. If they can actually filter the signal from the noise, I actually think that's pretty cool, and I hope some papers eventually get written and released, based on the methods. They've done the work, and all based on information that I wouldn't have a problem yelling to random people on a street corner.

      --
      It is pitch black. You are likely to be eaten by a grue.
    12. Re:2015: Still using Facebook by Anonymous Coward · · Score: 1

      Neoconservatism, which is Italian corporatism without neutered parliament instead of show unions, is the new religion. Don't need a god to lead sheep.

    13. Re:2015: Still using Facebook by Anonymous Coward · · Score: 2, Interesting

      So is death. If you accept the idea of the existence of God, then you probably accept the existence of some kind of afterlife and/or reincarnation. What's a lifetime of suffering, compared to an eternity of bliss? What is death, when it's the beginning of a happier time than life? God is the misunderstood parent getting their child inoculated. A moment of discomfort to avoid a worse fate later.

      The idea of the Christian God as evil isn't a new one, though. The Gnostics had the same idea nearly 2000 years ago, and I'm sure that it wasn't a new idea then, either.

    14. Re:2015: Still using Facebook by Anonymous Coward · · Score: 2, Interesting

      ...or... the notion of disbelieving in God is just a self-rationalization to enable one to live their life without feeling like they are actually have any real responsibility for their choices.

      If, when you die, that's it... you are done and over with, and none of the choices you would have made will actually have any bearing on you, then you can do whatever you want, live your life as irresponsibly as you want, in full assurance that death will enable you to escape whatever consequence might otherwise befall you.

      Or maybe... just maybe.... your choices in this life have an actual eternal implication. That's a heckuva lot of responsibility, and I don't blame you for preferring to disbelieve in it, because it's dramatically easier to cope with.

      Doesn't make it true, however. I'm not saying that you're wrong, only that disbelieving in God can be seen as just as cowardly an approach to life as belief in God is sometimes accused of being as a world view.

    15. Re:2015: Still using Facebook by Anonymous Coward · · Score: 0

      OK, so you're forced to use it and you've come on here to try and rationlise this decision, which you would rather not have been forced to make. I had a party recently. I sent everyone an email invitation. Good turn-out, no Facebook required, and we had plenty to talk about at the party!

    16. Re:2015: Still using Facebook by khellendros1984 · · Score: 1

      Quit going to church and you will finish the task of disassociating yourself from idiots and their idiotic behavior.

      If one lived alone in a cabin in the woods, one would still not succeed at escaping irrationality, since there's still one human nearby. People like to pretend that they're rational, but they're fooling themselves. You'll find the only example of non-idiotic humanity riding a unicorn, taking tea with the Flying Spaghetti Monster, in orbit about 1.3 AU out from a teapot inscribed "Bertrand" on the bottom.

      --
      It is pitch black. You are likely to be eaten by a grue.
    17. Re: 2015: Still using Facebook by Anonymous Coward · · Score: 0

      Similarly here. I only sign in via VPNs and it mostly tries to associate my entire life story with the town over 2,000 miles away where I have the most friends. I did grow up in that town but haven't been there in about 19 years and have no real connection to that town anymore.

    18. Re:2015: Still using Facebook by Anonymous Coward · · Score: 1

      What's the difference, data-mining wise, between having a Facebook account and willingly using your real name all over the place online?

      The difference is that online, I can use my real name for things that put me in positive light. I do not post stupid things with my real name. I don't even post stupid things as AC most of the time, but that's another thing.

      The difference is that with FB, they map ALL your associations, not just what you poast on there.

    19. Re:2015: Still using Facebook by Shakrai · · Score: 1

      I'm no more "forced" to use Facebook than I am "forced" to have a cell phone. I could get by with just a landline or even no phone. It would just be massively inconvenient. It's the same with Facebook. Yes I could live without it. I choose not to. You're welcome to decide differently if you wish.

      --
      I want peace on earth and goodwill toward man.
      We are the United States Government! We don't do that sort of thing.
    20. Re:2015: Still using Facebook by solios · · Score: 3, Insightful

      It doesn't matter if you use Facebook or not - they can already infer that TV shows and musicians exist via user data and automatically construct pages for them - WKRP In Cincinnati is a good example or was when I looked at it last summer. If they can infer media exists then it stands to reason that they can infer that you exist. Imagine that, if you will - a near future in which you have a fairly accurate social media profile rather you want one or not.

    21. Re: 2015: Still using Facebook by Anonymous Coward · · Score: 1

      When the strangers are deciding about health insurance, car insurance, job prospects/promotions, and a whole lot of other things then heck yes I care. If they do that based on my fb associations or any private data, it sure is something I would care about.

    22. Re:2015: Still using Facebook by Anonymous Coward · · Score: 1, Informative

      Dude, I have no belief in a god but I still feel an obligation to do good. Indeed, it's because I do not believe in a god that I have such a compulsion: my life is worth nothing beyond what I choose to do while I'm alive, and anybody can live for themselves, but to be worth anything requires living in pursuit of goodness.

      This doesn't mean I lack respect for those people who do good through religious compulsion, however. Indeed, I have far more respect for such people than those atheists who use lack of god as an excuse to do whatever they like, or - worse - try to impose some -ism (from American Capitalism to Soviet Communism) on the grounds that they are convinced they have 100% understanding of humanity and what's good for it. Ugh.

      So, (non-sarcastic) good for you, but there are other ways to do god's work (as you might see it) other than through believing in god :-).

    23. Re:2015: Still using Facebook by ranton · · Score: 1, Offtopic

      Or maybe... just maybe.... your choices in this life have an actual eternal implication. That's a heckuva lot of responsibility, and I don't blame you for preferring to disbelieve in it, because it's dramatically easier to cope with.

      If you are really worrying about the afterlife because your actions could damn you for eternity, any attempts are almost certainly going to be futile. There have been so many religions in the history of mankind, most likely you will sent to a land of ice because you never slaughtered a chicken at the beginning of the summer solstice.

      There is nothing cowardly about thinking your actions in this life are unlikely to help you in an afterlife. It is just common sense.

      --
      -- All that is necessary for the triumph of evil is that good men do nothing. -- Edmund Burke
    24. Re:2015: Still using Facebook by murdocj · · Score: 1

      Well, maybe because I have pictures from a trip that I want my friends (real friends) to see, and the easiest way is to post them on Facebook? It's like Willy Sutton's answer when they asked him why he robbed banks: "that's where the money is".

    25. Re:2015: Still using Facebook by Anonymous Coward · · Score: 1

      You need to hang out with a better class of Christians.

    26. Re:2015: Still using Facebook by Anonymous Coward · · Score: 1

      But without a god to say what is wrong or right, how do you know that what you're doing is really good? Perhaps you're doing the rankest evil, all unknowingly.

      Who can say how many lives you've impacted... negatively. How many wasted lives, destroyed careers, ruined youths... all by doing what you *thought* was good.

      To quote the great sage Lucy Van Pelt, "In all of mankind's history, there has never been more damage done than by people who 'thought they were doing the right thing.'" (18 Nov 1971)

    27. Re:2015: Still using Facebook by Actually,+I+do+RTFA · · Score: 2

      Imagine that, if you will - a near future in which you have a fairly accurate social media profile rather you want one or not.

      Near future? Ever since they convinced your "friends" to let them mine their phones for numbers, they figured out your social links, and developed fairly accurate profiles of you like 5+ years ago.

      --
      Your ad here. Ask me how!
    28. Re:2015: Still using Facebook by Anonymous Coward · · Score: 0

      There is nothing cowardly about thinking your actions in this life are unlikely to help you in an afterlife. It is just common sense.

      You may want to consider that it only seems like common sense because the alternative is outside of the scope of human life experience. Of course, all you've really done is further rationalize your view.

      You may want to consider why you feel a need to justify your worldview in the first place, however.

      And nobody with an iota of intelligence worries about the afterlife... they either don't believe in it in the first place, or else they have a belief system that has driven them to make life choices that will, to the best of their understanding or beliefs, avoid any eternally undesirable consequences.

    29. Re:2015: Still using Facebook by narcc · · Score: 1

      And nobody with an iota of intelligence worries about the afterlife

      The greatest minds in history excepted, of course.

      --
      Required reading for internet skeptics
    30. Re:2015: Still using Facebook by Wootery · · Score: 1

      If you accept the idea of the existence of God, then you probably accept the existence of some kind of afterlife and/or reincarnation.

      I don't agree. We have drugs that can knock you out for surgery. No consciousness at all, because it shuts off parts of your brain. And yet you are suggesting that consciousness can somehow survive the obliteration of the brain, and live on in an after-life.

      It seems to me that the question of an afterlife is easier to answer than the question of a creator.

    31. Re:2015: Still using Facebook by gsslay · · Score: 1

      Google "Facebook shadow profile". The near future already exists.

    32. Re:2015: Still using Facebook by mrchaotica · · Score: 1

      If, when you die, that's it... you are done and over with, and none of the choices you would have made will actually have any bearing on you, then you can do whatever you want, live your life as irresponsibly as you want, in full assurance that death will enable you to escape whatever consequence might otherwise befall you.

      If you need fear of damnation to stop you from doing evil things, then you are a sociopath.

      --

      "[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz

    33. Re: 2015: Still using Facebook by meustrus · · Score: 1

      where I have the most friends...and have no real connection to that town anymore.

      Right.

      --
      I sometimes ask revealing, often ignorant-seeming questions. Maybe they're harder to answer than you think.
    34. Re:2015: Still using Facebook by mythosaz · · Score: 1

      So you're willing to sell off your privacy for a few bucks?

      Parts of it, sure.

      That's what you're doing if you didn't realize it.

      Of course I realize what I'm giving up.

      Same goes for any 'rewards club' type cards at retailers: You're giving them permission to gather personally identifiable data on you, for a few measly bucks. How does it feel knowing that there are complete strangers out there that think they know you because of the data they collect on you about purchasing habits?

      It feels great sving money in exchange for something I place little value on. I DNFAG that Safeway knows I prefer Coke over Pepsi and that I buy the name-brand cheese that's on sale. I DNFAG that Facebook and Google buy this information and pair it with my driving habits and use it to try to feed me ads or sell it to other advertisers.

      How will you feel about it when someone gets it wrong?

      I won't care, no matter how outraged YOU get over it.

    35. Re:2015: Still using Facebook by cornjones · · Score: 1

      That's an interesting take on it. I often thought it was somewhat the other way around. ie, it would be very comforting to think of a paternal god figure watching and guiding events. If I were less disciplined, it would be 'nice' to forget my doubts and the (seemingly logical) conclusions of the lack of existence or at least lake of interest of the divine. imho, it takes courage to accept that we are not special souls that will live through eternity.

      that said, I wasn't being facetious above, i hadn't considered the weight of responsibility of actions that last for eternity... doesn't change my mind but I do like the orientation...B)

    36. Re:2015: Still using Facebook by kheldan · · Score: 1

      So how will you be feeling about having sold off this 'privacy' thing that you seem to value so little, when your health insurance premiums go through the roof because they know you like to drink Pepsi, which as everyone knows will lead to obesity and diabetes, and since you're one of those people who eat and drink unhealthy foods, you probably lead an overall unhealthy lifestyle, therefore heart disease is in your future too, and probably cancer -- therefore you're going to cost them a lot of money down the road -- therefore they charge you up the ass now, since you're such a big risk. Or maybe it's your life insurance company that raises your premium, or flat-out cancel your policy, since you're too big of a risk.

      Sound outrageous? Think again. With every year that passes that people throw away more and more of their right to privacy, more and more profiling of people's lives, right, wrong, accurate, or inaccurate, is happening. That's been the trend, and if nobody says anything about it, it'll continue until scenarios like the above start happening. Or worse things.

      --
      Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
    37. Re:2015: Still using Facebook by mythosaz · · Score: 1

      Charging at-risk people more for health insurance (myself included) doesn't sound outrageous at all. If I post to Facebook regularly about how I like to smoke cigarettes, my insurer should charge me the smoker rate.

      I find this no different than car insurance companies who'll let you connect an ODB2/GPS device to your car in exchange for better rates if you drive slower, accelerate slower, brake smoother, etc.

  3. All in the definitions by BarryHaworth · · Score: 5, Insightful

    The comment that the algorithm does better at predicting personality than a person's friends will depend very strongly on how you define a friend. I have a very large number of Facebook friends about whom I know almost nothing, so I am not at all surprised that an algorithm will do better.

    --
    I am a Statistician. One false move and you are a Statistic
    1. Re:All in the definitions by Bite+The+Pillow · · Score: 3, Informative

      It is not explicit, but it is clear that they did not use Facebook friends, preferring real ones instead.

  4. Reddit ? by denisbergeron · · Score: 2

    I hope nobody will ever be able to use my reddit's comments to predicts my personnality ever!!!

    --
    Ceci n'est pas une Signature !
    1. Re:Reddit ? by pkinetics · · Score: 2

      Don't worry. The NSA already has your file and is sharing it with the FBI and Interpol

  5. What if you're a Facebook Refusenick by Anonymous Coward · · Score: 0

    Heck, what if you won't even sign into Slashdot to leave this statement?

    1. Re:What if you're a Facebook Refusenick by Anonymous Coward · · Score: 0

      You don't exist. Go away.

    2. Re:What if you're a Facebook Refusenick by Anonymous Coward · · Score: 0

      Of course he exists. He's anonymous coward; he's everywhere on here AND on El Reg.

  6. Why are these factors? by Anonymous Coward · · Score: 0

    Why not any arbitrary factor like "prefers organization" or "prefers at least n but not more than p quiet evenings per month?"

    How about "diligently pretends to be these five things?"

    1. Re:Why are these factors? by Anonymous Coward · · Score: 3, Informative

      The names of the factors are guesses. Factor analysis looks at the covariance matrix of items, and finds sub-matrices of the total matrix that meaningfully covary. Each one of those sub-matrices is called a factor, or latent variable, which is measured by common covariation between the questions. The number of latent factors found in a questionnaire is typically derived both by theory (we made a questionnaire intended to measure these 6 different things) and empirical facts (of which typically would be Horn's parallel analysis or the Kaiser criterion [which simply means all eigen values of the covariance matrix that are greater than one]). The factors are named because that is what was a suitable commonality between the items first measured, along with external criterions like predicting other theoretically related constructs. The Big 5 are an enormously well studied problem space, and the stability and pervasiveness of these concepts have been well documented and linked to specific gene expressions, developmental trends, et cet.

    2. Re: Why are these factors? by Anonymous Coward · · Score: 0

      Except that the Big Five aren't orthogonal, which means they are fairly useless as a personality theory. It might as well be "two or three traits with which you might identify"

    3. Re: Why are these factors? by Anonymous Coward · · Score: 2, Interesting

      Except that the Big Five aren't orthogonal, which means they are fairly useless as a personality theory.

      Nothing is going to be explicitly orthogonal, and forcing them to be doesn't make the conceptual issue you seem to have any better or worse (n.b., orthogonal connotes a lack of meaningful correlation between the factors. What the parent is complaining about is that each of the latent factors is meaningfully correlated with the other four to different extents). First, we are of course talking about an exploratory (EFA) approach (haven't read the article but the 10-fold CV referenced above makes sense), and partially the distinction between principal components and factor analysis. The Big 5 model itself has been tested using SEM and confirmatory factor analysis, and the five interrelated but not redundant number of latent factors validates repeatedly. Second, remember that EFA solved using maximum likelihood can be used to assess the null hypothesis that no more factors are necessary to produce acceptable fit within the sample. Thus (although this, from a statistical fishing perspective, would be bad) we can actually sequentially find the minimum number of factors necessary to reproduce a non-significantly different correlation matrix, when compared to the original sample. Therefore, with multiple independent studies (and k-fold CV like this study did) we can say that five is pretty well empirically demonstrated.

      Now, the distinction between PCA and EFA. PCA is a technique explicitly designed to remove redundant covariation between items, and as such, the more dimensions you allow to represent the data, the better your overall fit. If you have nine items, nine principal components will capture 100% of the total, 9 item variance. However, it may be that 1 PC captures 65% of the variance, 2 represent 90% and the remaining 7 PCs make up the remaining 10. EFA works with correlations, and as such the most variance that can be reproduced is not 100%, but instead something analogous to the signal to noise ratio in engineering. It's a technique designed to identify and structure signals within noisy data, and therefore by default it doesn't assume everything being input is actually pure signal. Again, we're not measuring one thing chopped into 5 bits (or two, three etc) but 5 different things that have been repeatedly found to best fit data, when tested simultaneously, therefore controlling for each other. That means that the structure found represents statistically independent latents.

      However, that is not to say that the five latent factors do not share commonality that is meaningful (although when you run these procedures, a correlation of .3-.5 is generally pretty high, meaning at most a .1-.25% information redundancy between factors). If interested, and you have a sample and the required number of parameters, you can build hierarchical factor models, in which common latents underly multiple lower level latents, which then underly the observed item responses. Alternatively, you could even say that there is just one personality latent, let's call it `everything', and that only one latent underlies (it helps if you think of latents as causes of the observed variables/items) all 100 or whatever personality items, like in this study. There is a specific rotation procedure, the bifactor/Schmid–Leiman factor rotation.

      What this will do is examine global model fit: the question of whether the regression slopes from the observed items to the common covariances meaningfully reproduce the sample's covariances; does the data here empirically validate the correlational pattern we would expect if only one informational construct was represented (measured) in the data. Next (actually simultaneously), it will estimate whether, controlling for that one believed general latent factor, is there still meaningful latents estimable from the data. So, it's asking: is there still statistically significant relationships between items, once we've rem

    4. Re: Why are these factors? by meustrus · · Score: 1

      You should really sign in when posting something so informative (although some citations would be really nice). That way you can get good karma to give your posts an automatic +1 or +2 and it's easier to track when people reply.

      --
      I sometimes ask revealing, often ignorant-seeming questions. Maybe they're harder to answer than you think.
    5. Re: Why are these factors? by semper_statisticum · · Score: 1

      You should really sign in when posting something so informative (although some citations would be really nice). That way you can get good karma to give your posts an automatic +1 or +2 and it's easier to track when people reply.

      fair point. I lost my old account a good six years ago and never created a new one.

      --
      The Spanish Inquisition of Psychometrics; Burning all the heretics.
  7. Yeah sure by WillAffleckUW · · Score: 1

    If that were true I'd be a gay gerbil with diabetes, a heart condition, and wanting to date 20 yo girls.

    None are true.

    Now, 26 ...

    --
    -- Tigger warning: This post may contain tiggers! --
    1. Re:Yeah sure by Anonymous Coward · · Score: 0

      ...have you been using Facebook to browse gay gerbil porn? I didn't think any porn was allowed on Facebook.

  8. Targeted Advertising is About Targeting You by Anonymous Coward · · Score: 1

    The thing to know about all these "big data" targeted advertising systems is that they are not about finding stuff you might want to buy. They are about figuring out how best to press your buttons to manipulate you into buying whatever their customers have paid them to push on you. They don't care what kind of beer you like, they just care what kind of girls you like so that they can show you the beer commercial with the kinds of girls most likely to make you got out and buy a beer.

  9. What if I have no likes? by Gaygirlie · · Score: 2

    I have a Facebook-account due to family, but I make maybe one post a year there and I never like anything whatsoever. What does such an algorithm tell about me? I mean, it sounds to me like the algorithm is already biased towards certain kind of people from the get-go if it only applies to socially-outwards people who enjoy "liking" stuff on Facebook.

    1. Re:What if I have no likes? by AHuxley · · Score: 2

      Re " .... tell about me?"
      Its a bit like the people who use cryptography or have an interest privacy services?
      People Lacking Facebook Accounts Viewed As Suspicious (August 8, 2012)
      http://www.dailytech.com/Peopl...
      Beware, Tech Abandoners. People Without Facebook Accounts Are 'Suspicious.' (8/06/2012)
      http://www.forbes.com/sites/ka...
      It really depends on who is doing the tracking and the number of hops to friends and shared likes?

      --
      Domestic spying is now "Benign Information Gathering"
    2. Re:What if I have no likes? by Anonymous Coward · · Score: 0

      Facebook data analysis

      openness: 0
      conscientiousness: 0
      extraversion: 0
      agreeableness: 0
      neuroticism: 32767

      Let us display Prozac ads!

  10. Who fucking cares what this fucking spyware by Anonymous Coward · · Score: 0

    hands out a grades on my

    1. Re:Who fucking cares what this fucking spyware by gnupun · · Score: 1

      And you think the rest of the websites are saints when they install trackers like addthis.com scripts that can uniquely identify and track you without cookies? There is no openness about who they sell your info about your activity on their website. www == spyware

  11. machines vs factor analysis by Anonymous Coward · · Score: 0

    Regardless of the outcome ... if you mean "factor analysis" why did you say "machines"? Why not just say factor analysis.

  12. Personality is multifaceted by vix86 · · Score: 1

    All this algorithm will accomplish is showing the personality that a person shows to Facebook. The reason why it can "better predict a person's personality than their friends" is because people have different personalities around others. I've known this since high school. I had many friends and when I hung out with some just 1-on-1 they were chill and quiet; probably because that's how I was. But if you got these friends together in the same car or the same house, they suddenly became loud, rambunctious, and prone to doing stupid stuff. This still holds true today. So people have different personalities or faces depending on the people they are around and I'm sure Facebook has its own unique "face" as well.

    1. Re:Personality is multifaceted by coofercat · · Score: 1

      I saw an ad at the station for some company doing personality tests to 'unlock your potential'. That reminded me that I did a bunch of these at the start of my teens at school, primarily as a means to determine the sorts of jobs you might want to look into. I answered those tests in good faith, I wasn't trying to game them, and yet, without exception, they came out as "inconclusive", with no career suggestions at all (I wonder if they refund the test fee for that!?). I sure hope they've improved since then, because they were no use to back then.

  13. Glad I'm not on facebook... by Karmashock · · Score: 2

    Every day a little gladder.

    --
    I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
  14. Where is the questionnaire? by Anonymous Coward · · Score: 1

    Anyone have a link to the questionnaire? I'd like to validate my self views.

  15. 500+ question psychological tests by Trax3001BBS · · Score: 1

    Really get to know someone, I've taken many. One a year while working in the nuclear field (a requirement).

    The problem that's surfacing is it's biased towards the standard white American (ie: there is no Mexican version, even it's text is in English). This even outside of the nuclear field.

    1. Re:500+ question psychological tests by meustrus · · Score: 1

      it's biased towards the standard white American

      More like the standard white American college student research subject?

      --
      I sometimes ask revealing, often ignorant-seeming questions. Maybe they're harder to answer than you think.
  16. No Precision? by Champaklal · · Score: 1
    Usually Machine Learning systems have Precision measure, or relevance measure, if the rating they produce is greyscale. The article doesn't seem to mention in how many cases how close was system to predict the personalities.

    Also, the system needs, to be scalable, a classifier to judge the qualities of shared posts on which likes were made. The error of this classifier would act as a multiplier to the overall accuracy of system.

    They mostly explain the recall of the system, which is _slightly_ better than random pick (0.5). There is a lot of invention needed in this area.

  17. Test the Big Five by Anonymous Coward · · Score: 0

    I like the theory "Test the Big Five". However, the short article is very informative. This is really digital lyf man!

  18. And this surprises anyone? by jeffb+(2.718) · · Score: 2

    Actually, I'm surprised that the algorithm doesn't outperform spouses as well.

    Do any of your friends tirelessly catalog, index, analyze and correlate every chuckle or offhand comment you make within their earshot? Do you continue to talk freely in front of them, knowing they're doing it? If so, they can probably outperform this algorithm.

    The real fun will come from correlating the physiological signals coming in from fitness bands, eye-trackers, and eventually EEG pickups. Your soul will be laid barer than lunar regolith.

    1. Re:And this surprises anyone? by meustrus · · Score: 1

      Every human being (within a range of effectiveness correlated to social intelligence) does collect and analyze every interaction they have with every other human being. We don't have the same kind of large-scale stable memory that computers do so only the results of the analysis are remembered, which is why first impressions matter so much. All of this happens in the background of our minds, rather than with some kind of conscious cataloging process. In other words, our wetware includes special architecture to solve this exact problem in a memory-constrained environment.

      Don't underestimate the human brain, and don't underestimate how hard it is to replicate some of its built-in functions. This is hard stuff; we only got this smart either by the design of a much smarter being or by MILLIONS of years of evolution (or some combination of both). Sure, we know that our computers have a lot of processing power and access to ALL THE DATA, but actually writing the algorithm is a big achievement. A big achievement for a number of hard-working people.

      Technology only marches forward through the hard work of the great many individuals that make up our humanity. Don't forget or belittle that.

      --
      I sometimes ask revealing, often ignorant-seeming questions. Maybe they're harder to answer than you think.
  19. PNAS? by die+standing · · Score: 1

    "It's bulky, but I consider it carry on."

  20. Works great for narcissists! by Anonymous Coward · · Score: 0

    Basically this works for the kind of person who will like "thousands" of things on the internet. Which to me is a definite subset of personalities, not a broad spectrum. I, for one, try pretty damn hard not to like anything unless I see it in my facebook feed and want to throw the poster a bone for pointing it out or saying it. Hitting like anywhere on the web == building an advertising profile, and I noticed when Facebook started filling my feed with advertisements gleaned from my friends' likes, and I started telling them to quit doing that. So we're talking about possibly a stupid, vain, narcissistic subset of personalities.. that a computer is now better at judging personality-wise than the stupid, vain, narcissistic friends of these people. haha That's really news!