Scientific evidence for the MBTI assumptions

[Nails]

Hello all,

First of all, a disclaimer: I am new to MBTI and to this forum, I have been browsing through threads and did not immediately find anything on the issue, I am concerned with. So, if you guys have already discussed the issue below elsewhere or I am making the wrong assumptions about MBTI, please excuse me.

Anyway, the MBTI assumption of people being either E or I, N or S etc. seems to be valid for most of my entourage. Blackwater is very much ENTP, Economica and I are very much INTJ (even though I completely understand why people could mistake her for being E), Eco's boyfriend and Vortex are really ENFPs etc.

In general, the binarism of the four dimensions seems to be valid, most people are either one thing or the other, and there is very little doubt about what they are. Psychological mechanisms such as self-amplification (people do and improve at what they are already doing) can explain the binarism. The duality is very nice, we can then efficiently describe personalities and understand their social interaction between the various types.

But then, from time to time, I meet people that I have a really hard time classifying. Vortex has a best friend, we are pretty sure about this friend being F but the other dimensions escape us. I thought she was ENFP, Eco is fairly convinced she is ISFJ, Vortex believes her friend is xNFx but even though Vortex has known her friend since high school, she can't say for sure about the two remaining dimensions.

My concern is now, what does this mean for the MBTI binarism? If the binarism does indeed hold, with everybody being one thing or the other, then typology misclassifications may occur due to lack of knowledge or misunderstandings, but in general a large number of MBTI analysts should agree on the personality type of a specific individual.

So, what I would like to know, is this really what is happening? If a large number of analysts examines one individual, will, let's say 95 % of them or more, agree that this person is indeed e.g. ENFP? Or could it be that 45 % would say Sensing, while the remaining 55 % would pick N?

Do we have any statistics on this issue? I have seen a lot of data on scientists being mainly INxJs, policemen being all S etc, but I have not seen any statistics describing the classification of one specific individual by a large number of MBTI analysts. Please inform me, if you are aware of such statistics on the certitude of the MBTI classification of individuals.

I am sure that everyone (who knows him obviously) will agree that Eco's boyfriend is ENFP, but I could very well imagine that we would all totally disagree on Vortex' old friend. What does this mean? Could it be that most people are one thing or the other, but that some are in between? In that case, would it be more appropriate to describe people using percentages, e.g. 65 % N, 35 % S etc.?

Any thoughts or ideas on the subject are most appreciated.

BR

Edit: We are sure about the type of Vortex, it is her friend that is uncertain.

[ptgatsby]

Originally Posted by Nails

Do we have any statistics on this issue? I have seen a lot of data on scientists being mainly INxJs, policemen being all S etc, but I have not seen any statistics describing the classification of one specific individual by a large number of MBTI analysts. Please inform me, if you are aware of such statistics on the certitude of the MBTI classification of individuals.

Someone mentioned this to me before and I did a bit of reading on it, which I wasn't aware of. However, I have generally concluded that he was correct - the instrument is kurotically distributed. The binomial push really is a forced method after the instrument (whereas the instrument uses binary choices, which makes the argument that much more complicated). Course all this says is that the instrument is much more similar to other inventory responses tests.

In any case, the analysts base it on the instrument results and the certainty measurement in the test. Reliability on the instrument is relatively solid, so analysts are generally as reliable as the reliability of the instrument (with some deviation).

However, while I don't know of any statistics on the ability of people to read other types accurately... I do know that relatively speaking, and I must emphasise this, a stranger not even meeting the person can predict the person's type just as well by looking at his personal living space for 15-20 minutes as a long term friends (many years of knowing eacf other). The least accurate would be the ability to judge "at a distance" (ie: stranger meeting the person, observing or reading interviews/etc).

I don't know if that answers any of your questions, but if not, I might be able to answer a more specific question (rather than interpret the question "what does it mean for MBTI binarism" )

[Introverts_Unite!]

The statistical evidence for the Myers-Briggs Type Indicator and associated research over the years -
(but note this is NOT for other copycat indicators like Kiersey etc) -
can be found in the Manual, available through CPP - Consulting Psychologists Press, the publisher of the MBTI.
The Manual is pretty dry (not to mention expensive) but it's important if you want to seriously tackle the theoretical basis.
I became a qualified administrator for Form J in 1996 (prior to Form M). I love the stuff but it's expensive to keep up with all the seminars unless you can get a good tax writeoff, so I haven't done much lately.

the following description was copied/pasted from the publisher's website:

CPP Item Detail - MBTI Manual (A)

MBTI

[Maverick]

Originally Posted by ptgatsby

Someone mentioned this to me before

That must have been me if I remember correctly.

In response to the OP, there's quite a bit of litterature on this already so you should take the time to google it up. Basically, there are no sound statistical reasons for asserting that most people have a preference.

There is little scientific evidence to many of the MBTI's assumptions.

[MerkW]

Originally Posted by Nails

Hello all,

First of all, a disclaimer: I am new to MBTI and to this forum, I have been browsing through threads and did not immediately find anything on the issue, I am concerned with. So, if you guys have already discussed the issue below elsewhere or I am making the wrong assumptions about MBTI, please excuse me.

Anyway, the MBTI assumption of people being either E or I, N or S etc. seems to be valid for most of my entourage. Blackwater is very much ENTP, Economica and I are very much INTJ (even though I completely understand why people could mistake her for being E), Eco's boyfriend and Vortex are really ENFPs etc.

In general, the binarism of the four dimensions seems to be valid, most people are either one thing or the other, and there is very little doubt about what they are. Psychological mechanisms such as self-amplification (people do and improve at what they are already doing) can explain the binarism. The duality is very nice, we can then efficiently describe personalities and understand their social interaction between the various types.

But then, from time to time, I meet people that I have a really hard time classifying. Vortex has a best friend, we are pretty sure about her being F but the other dimensions escape us. I thought she was ENFP, Eco is fairly convinced she is ISFJ, Vortex believes she is xNFx but even though they have known each other since high school, she can't say for sure about the two remaining dimensions.

My concern is now, what does this mean for the MBTI binarism? If the binarism does indeed hold, with everybody being one thing or the other, then typology misclassifications may occur due to lack of knowledge or misunderstandings, but in general a large number of MBTI analysts should agree on the personality type of a specific individual.

So, what I would like to know, is this really what is happening? If a large number of analysts examines one individual, will, let's say 95 % of them or more, agree that this person is indeed e.g. ENFP? Or could it be that 45 % would say Sensing, while the remaining 55 % would pick N?

Do we have any statistics on this issue? I have seen a lot of data on scientists being mainly INxJs, policemen being all S etc, but I have not seen any statistics describing the classification of one specific individual by a large number of MBTI analysts. Please inform me, if you are aware of such statistics on the certitude of the MBTI classification of individuals.

I am sure that everyone (who knows him obviously) will agree that Eco's boyfriend is ENFP, but I could very well imagine that we would all totally disagree on Vortex old friend. What does this mean? Could it be that most people are one thing or the other, but that some are in between? In that case, would it be more appropriate to describe people using percentages, e.g. 65 % N, 35 % S etc.?

Any thoughts or ideas on the subject are most appreciated.

BR

Well, MBTI isn't really a "Yes/No," "0/1," Binary system that you seem to think it is. There are 8 "cognitive functions" that make up each type. There are judging functions and perceiving functions, which can then be further broken down into the attitude of the function (i.e. extroversion/introversion), like so;

1. Judging Functions: 2. Perceiving Functions
- Extroverted Feeling (Fe) - Extroverted Sensing (Se)
- Introverted Feeling (Fi) - Introverted Sensing (Si)
- Extroverted Thinking (Te) - Extroverted Intuition (Ne)
- Introverted Thinking (Ti) - Introverted Intuition (Ni)

So for example, if you have trouble with typing Vortex accurately on the E/I, S/N, and J/P dichotomies, you should try looking at it from a functional perspective. I am too lazy to go off on a rant about Jungian functions, so I will give you some useful websites. Here is one website: Understanding the Eight Jungian Cognitive Processes / Eight Functions Attitudes
Here is another: Jungian Function Theory
And a last one: The Lenore Thomson Exegesis Wiki

When you read through some of these pages you will find that an ISFJ and an ENFP are radically different (almost opposite, in fact), and thus should be easy to tell apart. If it still seems difficult, perhaps Vortex is neither an ISFJ nor an ENFP. INFJ? INFP? Etc. After becoming more familiar with Jung's cognitive processes, it becomes much easier to type people.

[ptgatsby]

Originally Posted by Maverick

That must have been me if I remember correctly.

Regarding the distributions of the instrument, it was Fridayeyes that PMed me about it... but I think this has come up a lot between us and others. I'm slightly confused about what the OP was asking though, so I kind of hit it with a broad brush.

This is a common problem... is it the instrument or the interpretation that is the issue? I think the assumption made in the OP is about how the instrument is given (ie: the degree of interpretation), which may be the confusion.

Course, CAPT is not very open about outsiders building their own response interpretations (including using lawyers), so the whole argument is quite involved.

[Economica]

Originally Posted by Nails

But then, from time to time, I meet people that I have a really hard time classifying. Vortex has a best friend, we are pretty sure about this friend being F but the other dimensions escape us. I thought she was ENFP, Eco is fairly convinced she is ISFJ, Vortex believes her friend is xNFx but even though Vortex has known her friend since high school, she can't say for sure about the two remaining dimensions.

I know this is totally tangential to the main point () but for the record, I don't have an opinion ('fairly convinced') about said friend's type (except for the IF) though I may have given that impression. I remember pointing out that she herself identified as S when she first heard about the dimensions and that our definitely ISFJ friend thinks of her as 'more like me than like all you Ns', but that could easily be true of an INFP as well (with dominant Fi instead of dominant Ni/Ne like most of the Ns the ISFJ was referring to).

That said, the problem of some people escaping classification remains... Though I have to wonder how much is due to our relative typing inexperience. For instance, I don't know any female INFP well enough to compare with Vortex's friend.

Originally Posted by Merkw

Well, MBTI isn't really a "Yes/No," "0/1," Binary system that you seem to think it is. There are 8 "cognitive functions" that make up each type. (...) After becoming more familiar with Jung's cognitive processes, it becomes much easier to type people.

I agree that Nails needs to acquaint himself with function theory (and temperament theory), but I know all the theory and the problem remains. Are you saying you have never been unable to type someone? If so, may I ask how many people you have typed (where the accuracy of the typing has been confirmed by the person and preferably also by those who know the person well)?

I sure hope my failures are due to typing inexperience...

[MerkW]

Originally Posted by Economica

I agree that Nails needs to acquaint himself with function theory (and temperament theory), but I know all the theory and the problem remains. Are you saying you have never been unable to type someone? If so, may I ask how many people you have typed (where the accuracy of the typing has been confirmed by the person and preferably also by those who know the person well)?
I sure hope my failures are due to typing inexperience...

I never doubted thy knowledge of the system. I was merely responding to Nails. And, yes, of course there are many occasions where I am unable to type someone, yet these occasions are usually with people whom I do not know very well. With people I know, I usually am quite sure that the person is either one of two possible types.

[Economica]

Originally Posted by Merkw

I never doubted thy knowledge of the system. I was merely responding to Nails.

Oh, I know.

And, yes, of course there are many occasions where I am unable to type someone, yet these occasions are usually with people whom I do not know very well. With people I know, I usually am quite sure that the person is either one of two possible types.

1. One of two possible types? That's not good enough!

2. You may be quite sure, but that's not good enough either. The first year I knew about MBTI there wasn't anyone I didn't think I had typed correctly. What I asked was: "How many people have you typed where the accuracy of the typing has been confirmed by the person and preferably also by those who know the person well?"

[Nails]

Thank you for the responses, so far. I am not quite sure what ptgatsby means by "kurotical" distribution, even though I think we are on the right track.

Let us imagine the following experiment and two possible outcomes: We ask a 100 senior members of MBTI central to type a random high school class with 30 students. 3000 interviews later, all the students have been analyzed a 100 times each and we can study the certitude of the typology. To keep the math simple, we will just study the N/S dimension, not the entire typology.

Outcome I:

There is 100 % agreement for every student in the class. This would mean that 1) the typology does indeed hold and 2) the MBTI seniors really do know their stuff.

Outcome II:

There is > 90 % agreement for 10 students. There is 75 % agreement for 10 others and only 50 % agreement for the remaining 10. (50 % agreement means that a student is typed as 50 % N, 50 % S).

Here we are in trouble, and we must try to determine the origin of the deviations in the results. Possible consequences for MBTI that I can imagine are the following:

a) Humans have no preference for the four dimensions, N does not contradict S in a personality and the MBTI assumptions do not hold.

b) People do have preferences, but these should be analyzed in a more relative manner. We could say that person A is more N than B but more S than C. People should be typed by comparison and percentages would be more suitable for describing preferences.

c) People have preferences, they are indeed binary, but the MBTI central seniors were having a hangover the day the interviews were conducted from too much and the day before.

I guess a) and b) are what ptgatsby means by a problem with the "instrument" and c) is with the "interpretation"?

My feeling, inspired by my own difficulty of classifying people, is that Outcome II of the experiment is indeed very possible, and I would be most interested in more information to find out whether a), b), c) or something else(?) is the explanation for the result.

So people, what are your thoughts on this?

And do you have any idea whether such an experiment has ever been carried out? Statistics on this would be most interesting.