7 ms·

This is so poorly thought out. I really don't get why some people can't seem to tell the difference between things like MBTIs and astrological signs/zodiacs/hor

This is so poorly thought out. I really don't get why some people can't seem to tell the difference between things like MBTIs and astrological signs/zodiacs/horoscopes in terms of their potential to classify people in a meaningful way... One is an arbitrary mapping of a person's date of birth to an set of traits and prophesies. The other is a brief summary of a person's personality/behavioral inclinations based on a survey of that person's stated behavior and inclinations. When you say MBTI can be "just as arbitrary," what you're claiming is that it might be true that there is zero correlation between how any individual person of a given personality type answers any of the 93 MBTI questions. Sure, there is variation in people's self-assessments (and personalities for that matter, but let's ignore that for the moment) over time, but it wouldn't be "just as arbitrary" unless it had no correlation at all with basically anything about the person. I find that claim to be completely implausible. The only way it could be true that it is meaningless is if upon repeated testings, knowing a person's formerly reported MBTI provided no insight at all into what MBTIs are more likely than for the average person in subsequent testings. That's certainly not the case that's been found in the research, so at the very least, it provides insight into what a person thinks that they are like. Even if it were the case that all the MBTIs are only related to positive traits (which isn't true), the idea that it is meaningless is just nonsense.

Analemma_ 10y ago
> I really don't get why some people can't seem to tell the difference between things like MBTIs and astrological signs/zodiacs/horoscopes Then let me try to help clarify. MBTI has no predictive power ("I'm an INTP, so... ?") and is not falsifiable. Those are the delineators between science and pseudoscience, so that's why I bucket it with astrology.
- trendia 10y ago
  Add to that "People receive different MBTI results even in the same week."
  - 0xfffafaCrash 10y ago
    That proves what? If you want to argue that people's MBTI fluctuates too wildly to be meaningful, the proper question is whether there's any information gain from knowing a person's previous MBTI results for subsequent tests, not whether it is exactly the same. And the answer to that is yes. If you know I scored INTP on my last test, am I equally likely to score say ESFJ on a subsequent test as opposed to INTP or something closer to it (there are four dimensions after all) than a randomly selected person? Nope. If I ask you what your weight and height is today, it's indicative of what your weight and height will be a year from now even if the number doesn't fit into exactly the same rounded range. Doesn't mean weight and height are meaningless if the answers change classifications a bit.
    - DanBC 10y ago
      Height and weight are things we can objectively measure.
    - ivan_gammel 10y ago
      Some people may score same results for the entire life, just as some unlucky molecula of oxygen can stay in same cubical centimeter of the room for a long time. Statistically it's possible. But it does not matter, when you need predictions for the entire ensemble. If real predictive power of MBTI is low, if the cost of mistake is high (e.g. when you do not hire a star because of this test or when you promote to management position a guy with promising test score), then this typology does not make sense and must be avoided. Since there's no scientific proof of predictive power of this theory, then it's garbage.
    - Bartweiss 10y ago
      > whether there's any information gain from knowing a person's previous MBTI results for subsequent tests That doesn't seem like the proper question. Specifically, it works only to predict future MBTI results, not anything further. That's fine for height and weight because those values are robust to small/moderate changes in value. MBTI already has low predictive power about real-world content, and high sensitivity to change (on the margins; it also suffers from applying a clustered model to non-clustered data). So if retest reliability is anything less than excellent, I worry that our predictive power has been almost totally destroyed. To provide a new analogy, this is like variance in number of fingers. The significance of 11 vs 10 vs 9 isn't proportional to magnitude, so we wouldn't accept "small" counting errors. None of that says that "I'm an INTP" is meaningless, but I suspect that MBTI is no better, or even worse, than non-formalized personality summaries.
- 0xfffafaCrash 10y ago
  If say some person knows two people and that one tested as INTP and other as ESFJ and doesn't know for a fact who had which test results. Are you really sure they won't have better than even odds at figuring out which is which based on their interactions with the people that don't involve asking for their MBTI test results? If so, based on what study? If you can't demonstrate that, on what do you base that it has no predictive power?
  - Angostura 10y ago
    Given the fact that repeated testing over a period often comes out with entirely different results - yes.
    - 0xfffafaCrash 10y ago
      By "entirely different" you mean not the exact same classification or a classification independent of the previous classification? If the latter, the evidence does not support you.
  - floopidydoopidy 10y ago
    I agree that it has a use: it helps identify gullible people. Extremely valuable in that regard.
    - Graphon1 10y ago
      ha, got a laugh from that.
  - cazum 10y ago
    You bring up an interesting case I think even you failed to consider: Since mbti essentially neuters it's own usefulness in the "round those percentages down to binary" stage, you could end up with a situation where an INTP and an ESFJ have only an 8% total difference in mbti-measured personality between them.
    - 0xfffafaCrash 10y ago
- pcmaffey 10y ago
  You're doing a disservice to astrology. MBTI is a subjective categorization. Astrology is more like your DNA. You're born with a specific set pattern. Just like we don't understand what most of our genetic patterns mean, we don't understand what most of our astrological patterns mean.
  - triplesec 10y ago
    There are no data to support the magical thinking of astrology. You are unlikely to find supporters here for your assertions of pre-enlightenment pseudo science
    - deleted 10y ago
      [deleted]
  - CoryG89 10y ago
    Much of our DNA may not mean very much at all, just like our astrological patterns. http://www.nytimes.com/2015/03/08/magazine/is-most-of-our-dna-garbage.html http://www.nytimes.com/2015/03/08/magazine/is-most-of-our-dn...
- amelius 10y ago
  .
  - AlexandrB 10y ago
    That's meaningless unless you confirm that their fitness for that task was actually correlated to their MTBI, e.g. by mixing those "fit" and "unfit" (based on MTBI) on the same task and comparing their performance. I'm pretty sure most companies don't do this. They just assume MTBI has predictive power and use it anyway since it gives them something to go on besides gut instinct.
    - amelius 10y ago
      Well, I know for sure that a person with an INTJ personality type is not suited for marketing and sales (statistically speaking of course). Would you claim otherwise?
      - foopityfop 10y ago
        Yes I would. Given the inconsistency of results that the Myers-Briggs test outputs for individuals, the personality of that person who tested as an INTJ could be far from it normally. Furthermore, your willingness to buy into the narrative (and others' willingness to also believe it) that by categorizing certain people into stereotypes and assuming that most of these people tend to excel at a particular set of tasks is most likely what limits them from excelling at tasks that lie outside of their respective sets just as much as their true predisposition to not excelling at them.
        amelius 10y ago
        Then please point me to the research, because the article does a lousy job at it. Saying that any profiling technique has zero predictive value is a very bold claim. Even one's astrological sign has predictive value: [1]. And yes, this has been scientifically proven. [1] http://www.medicaldaily.com/how-birth-month-influences-personality-traits-ironic-science-astrological-signs-333274 http://www.medicaldaily.com/how-birth-month-influences-perso...
ivraatiems 10y ago
When I talk about external validity, what I mean is that the MBTI does not predict how people actually behave. What it says about you, and what you actually are, do not line up often enough or non-trivially enough for it to be valuable. The problem is not variation over time - that's fine. The problem is that when someone gets a result, that result doesn't say what it claims to about them. It's similar to astrology because while it has a series of well-defined rules for making a decision, that decision does not reflect reality. It is therefore effectively arbitrary. Both MBTI and astrology are internally valid - that is, the same person will get the same or similar results the majority of the time. That doesn't mean they mean anything.
- 0xfffafaCrash 10y ago
  Do you have any serious evidence that shows that it doesn't have external validity? If say some person knows two people and that one tested as INTP and the other as ESFJ and this person doesn't know for a fact who had which test results. Are you really sure they won't have better than even odds at figuring out which is which based on their interactions with the people that don't involve asking for their MBTI test results? If so, based on what study? It's clear I wouldn't be able to tell them apart based on their birthday (unless they were super young or something), but it's not at all clear that it's the case for MBTI.
  - ivraatiems 10y ago
    That's not how science works. The burden is not on me to prove MBTI does not have external validity, the burden is on the MBTI to prove it does have it. You have the chain of cause and effect backwards. If you say "the sky is green," it's not my job to prove to you it's not. It's your job to prove it is. You're the one making the claim. But here is a (more politely worded than I) paper on the MBTI's ineffectiveness for your perusal: http://epublications.bond.edu.au/cgi/viewcontent.cgi?article=1026&context=hss_pubs&sei-redir=1 http://epublications.bond.edu.au/cgi/viewcontent.cgi?article... - simply googling "mbti external validity" will also give you plenty of explanation. I also recommend looking at the many studies that review cites, since its whole purpose is amassing information on whether the MBTI is effective.
cazum 10y ago
I believe the "arbitrary zodiac" claim is made toward people that attempt to extrapolate behavior out of mbti types. For example, "INFJs are strong leaders" is as arbitrary as saying "aquarius's are strong leaders" The problem i, and many other people find with the mbti is that most of its users, and even scientific apologists, can't help but fall into the trap of categorizing people into perceived behavioral trends based on their types, which is at best, scientifically invalid, and at worse, harmful.
II2II 10y ago
To be fair, the comparison to horoscopes was in a very specific context: the results are presented in general terms that people will be more likely to self-identify with. That particular excerpt doesn't really say much about the predictive power of MBTIs, aside from pointing to a study that suggests that the predictive power doesn't really matter when individuals assess their own results. Of course other parts of the article talk about the predictive power of the personality test. On the other hand, those excerpts don't talk about horoscopes.
psyc 10y ago
You are correct, but I predict you will not have much success arguing this point in this forum. Hacker News already made up its mind that psychological tests don't predict anything.
deleted 10y ago
[deleted]
YeGoblynQueenne 10y ago
>> a brief summary of a person's personality/behavioral inclinations based on a survey of that person's stated behavior and inclinations. I'm really a very nice person. I'm magnanimous, full of goodwill and compassion and everyone I meet immediately likes me. I am intelligent and brave and very gregarious. I am the best person to be around when you need a shoulder to cry on because I have a deep understanding of human nature, thanks to my very high emotional intelligence. That is the problem with taking into account people's stated behaviour and inclinations.

Analemma_ 10y ago

> I really don't get why some people can't seem to tell the difference between things like MBTIs and astrological signs/zodiacs/horoscopes Then let me try to help clarify. MBTI has no predictive power ("I'm an INTP, so... ?") and is not falsifiable. Those are the delineators between science and pseudoscience, so that's why I bucket it with astrology.

trendia 10y ago
Add to that "People receive different MBTI results even in the same week."
- 0xfffafaCrash 10y ago
  That proves what? If you want to argue that people's MBTI fluctuates too wildly to be meaningful, the proper question is whether there's any information gain from knowing a person's previous MBTI results for subsequent tests, not whether it is exactly the same. And the answer to that is yes. If you know I scored INTP on my last test, am I equally likely to score say ESFJ on a subsequent test as opposed to INTP or something closer to it (there are four dimensions after all) than a randomly selected person? Nope. If I ask you what your weight and height is today, it's indicative of what your weight and height will be a year from now even if the number doesn't fit into exactly the same rounded range. Doesn't mean weight and height are meaningless if the answers change classifications a bit.
  - DanBC 10y ago
    Height and weight are things we can objectively measure.
  - ivan_gammel 10y ago
    Some people may score same results for the entire life, just as some unlucky molecula of oxygen can stay in same cubical centimeter of the room for a long time. Statistically it's possible. But it does not matter, when you need predictions for the entire ensemble. If real predictive power of MBTI is low, if the cost of mistake is high (e.g. when you do not hire a star because of this test or when you promote to management position a guy with promising test score), then this typology does not make sense and must be avoided. Since there's no scientific proof of predictive power of this theory, then it's garbage.
  - Bartweiss 10y ago
    > whether there's any information gain from knowing a person's previous MBTI results for subsequent tests That doesn't seem like the proper question. Specifically, it works only to predict future MBTI results, not anything further. That's fine for height and weight because those values are robust to small/moderate changes in value. MBTI already has low predictive power about real-world content, and high sensitivity to change (on the margins; it also suffers from applying a clustered model to non-clustered data). So if retest reliability is anything less than excellent, I worry that our predictive power has been almost totally destroyed. To provide a new analogy, this is like variance in number of fingers. The significance of 11 vs 10 vs 9 isn't proportional to magnitude, so we wouldn't accept "small" counting errors. None of that says that "I'm an INTP" is meaningless, but I suspect that MBTI is no better, or even worse, than non-formalized personality summaries.
0xfffafaCrash 10y ago
If say some person knows two people and that one tested as INTP and other as ESFJ and doesn't know for a fact who had which test results. Are you really sure they won't have better than even odds at figuring out which is which based on their interactions with the people that don't involve asking for their MBTI test results? If so, based on what study? If you can't demonstrate that, on what do you base that it has no predictive power?
- Angostura 10y ago
  Given the fact that repeated testing over a period often comes out with entirely different results - yes.
  - 0xfffafaCrash 10y ago
    By "entirely different" you mean not the exact same classification or a classification independent of the previous classification? If the latter, the evidence does not support you.
- floopidydoopidy 10y ago
  I agree that it has a use: it helps identify gullible people. Extremely valuable in that regard.
  - Graphon1 10y ago
    ha, got a laugh from that.
- cazum 10y ago
  You bring up an interesting case I think even you failed to consider: Since mbti essentially neuters it's own usefulness in the "round those percentages down to binary" stage, you could end up with a situation where an INTP and an ESFJ have only an 8% total difference in mbti-measured personality between them.
  - 0xfffafaCrash 10y ago
pcmaffey 10y ago
You're doing a disservice to astrology. MBTI is a subjective categorization. Astrology is more like your DNA. You're born with a specific set pattern. Just like we don't understand what most of our genetic patterns mean, we don't understand what most of our astrological patterns mean.
- triplesec 10y ago
  There are no data to support the magical thinking of astrology. You are unlikely to find supporters here for your assertions of pre-enlightenment pseudo science
  - deleted 10y ago
    [deleted]
- CoryG89 10y ago
  Much of our DNA may not mean very much at all, just like our astrological patterns. http://www.nytimes.com/2015/03/08/magazine/is-most-of-our-dna-garbage.html http://www.nytimes.com/2015/03/08/magazine/is-most-of-our-dn...
amelius 10y ago
.
- AlexandrB 10y ago
  That's meaningless unless you confirm that their fitness for that task was actually correlated to their MTBI, e.g. by mixing those "fit" and "unfit" (based on MTBI) on the same task and comparing their performance. I'm pretty sure most companies don't do this. They just assume MTBI has predictive power and use it anyway since it gives them something to go on besides gut instinct.
  - amelius 10y ago
    Well, I know for sure that a person with an INTJ personality type is not suited for marketing and sales (statistically speaking of course). Would you claim otherwise?
    - foopityfop 10y ago
      Yes I would. Given the inconsistency of results that the Myers-Briggs test outputs for individuals, the personality of that person who tested as an INTJ could be far from it normally. Furthermore, your willingness to buy into the narrative (and others' willingness to also believe it) that by categorizing certain people into stereotypes and assuming that most of these people tend to excel at a particular set of tasks is most likely what limits them from excelling at tasks that lie outside of their respective sets just as much as their true predisposition to not excelling at them.
      - amelius 10y ago
        Then please point me to the research, because the article does a lousy job at it. Saying that any profiling technique has zero predictive value is a very bold claim. Even one's astrological sign has predictive value: [1]. And yes, this has been scientifically proven. [1] http://www.medicaldaily.com/how-birth-month-influences-personality-traits-ironic-science-astrological-signs-333274 http://www.medicaldaily.com/how-birth-month-influences-perso...

ivraatiems 10y ago

When I talk about external validity, what I mean is that the MBTI does not predict how people actually behave. What it says about you, and what you actually are, do not line up often enough or non-trivially enough for it to be valuable. The problem is not variation over time - that's fine. The problem is that when someone gets a result, that result doesn't say what it claims to about them. It's similar to astrology because while it has a series of well-defined rules for making a decision, that decision does not reflect reality. It is therefore effectively arbitrary. Both MBTI and astrology are internally valid - that is, the same person will get the same or similar results the majority of the time. That doesn't mean they mean anything.

0xfffafaCrash 10y ago
Do you have any serious evidence that shows that it doesn't have external validity? If say some person knows two people and that one tested as INTP and the other as ESFJ and this person doesn't know for a fact who had which test results. Are you really sure they won't have better than even odds at figuring out which is which based on their interactions with the people that don't involve asking for their MBTI test results? If so, based on what study? It's clear I wouldn't be able to tell them apart based on their birthday (unless they were super young or something), but it's not at all clear that it's the case for MBTI.
- ivraatiems 10y ago
  That's not how science works. The burden is not on me to prove MBTI does not have external validity, the burden is on the MBTI to prove it does have it. You have the chain of cause and effect backwards. If you say "the sky is green," it's not my job to prove to you it's not. It's your job to prove it is. You're the one making the claim. But here is a (more politely worded than I) paper on the MBTI's ineffectiveness for your perusal: http://epublications.bond.edu.au/cgi/viewcontent.cgi?article=1026&context=hss_pubs&sei-redir=1 http://epublications.bond.edu.au/cgi/viewcontent.cgi?article... - simply googling "mbti external validity" will also give you plenty of explanation. I also recommend looking at the many studies that review cites, since its whole purpose is amassing information on whether the MBTI is effective.

cazum 10y ago

I believe the "arbitrary zodiac" claim is made toward people that attempt to extrapolate behavior out of mbti types. For example, "INFJs are strong leaders" is as arbitrary as saying "aquarius's are strong leaders" The problem i, and many other people find with the mbti is that most of its users, and even scientific apologists, can't help but fall into the trap of categorizing people into perceived behavioral trends based on their types, which is at best, scientifically invalid, and at worse, harmful.

II2II 10y ago

To be fair, the comparison to horoscopes was in a very specific context: the results are presented in general terms that people will be more likely to self-identify with. That particular excerpt doesn't really say much about the predictive power of MBTIs, aside from pointing to a study that suggests that the predictive power doesn't really matter when individuals assess their own results. Of course other parts of the article talk about the predictive power of the personality test. On the other hand, those excerpts don't talk about horoscopes.

psyc 10y ago

You are correct, but I predict you will not have much success arguing this point in this forum. Hacker News already made up its mind that psychological tests don't predict anything.

deleted 10y ago

[deleted]

YeGoblynQueenne 10y ago

>> a brief summary of a person's personality/behavioral inclinations based on a survey of that person's stated behavior and inclinations. I'm really a very nice person. I'm magnanimous, full of goodwill and compassion and everyone I meet immediately likes me. I am intelligent and brave and very gregarious. I am the best person to be around when you need a shoulder to cry on because I have a deep understanding of human nature, thanks to my very high emotional intelligence. That is the problem with taking into account people's stated behaviour and inclinations.