
Birth Order Effects Exist and Are Strong - imartin2k
http://slatestarcodex.com/2018/01/08/fight-me-psychologists-birth-order-effects-exist-and-are-very-strong/
======
tgb
I was taught birth order effects in middle school in the 2000's in the US in a
"health" class (in the same unit we also did handwriting analysis). We were
literally shown a video of a family in which everyone explained why they were
the rebel as the second child, the overachiever as the first child, the
spoiled brat as the youngest, etc. Birth order effects might exist... but even
if that were true we _should not_ teach them to middle-schoolers as
determining their life. This is for the same reason that we would not want a
video of a "typical community" showing a white male doctor, a white female
kindergarten teacher, and a black male janitor even if all of those
occupations are statistically more likely to be held by those demographics
than the others. Because we live in a time and a place where children get to
choose that they are not like their statistical cohort if they put their mind
to it.

The only positive thing I took out of that class was the number of other
students going "this is bullshit, I'm a first child and am the rebel of the
family" or whatever. And it was a good introduction to not trusting authority.

~~~
AstralStorm
Devil's advocate here: why shouldn't we teach people their position in life is
largely predetermined? We have precedent in Confucian and Hinduist
philosophies.

If it isn't, wouldn't we state so? I am looking for an utilitarian valid and
true argument.

~~~
pas
We should teach people about these things that have a great effect on their
life trajectory, but maybe, just maybe, middle-schoolers are not ready to
appreciate the complex interplay between overlapping Gauss curves, path
dependence, self-fulfilling prophecies.

Of course people should know where they come from and what does that mean,
just as it's usually important to tell kids if they are adopted or have some
serious congenital problem. (Usually because it can mean life or death, as we
all seen it in [medical] dramas where people search for organ donors and so
on.) But the question of when and how to tell is a big one, and there are
probably many good answers, but alas probably all of them are forged in hard
compromises between hurting the kid now, or letting them finding it out by
accident.

~~~
d33
> maybe, just maybe, middle-schoolers are not ready to appreciate the complex
> interplay between overlapping Gauss curves, path dependence, self-fulfilling
> prophecies

I'd say that only applies if you want it to. Otherwise, are you suggesting
that there's a specific age which one needs to reach in order to grok basics
of statistics?

~~~
pas
No, I'm just stating the current reality of lack of basic rationality in
education, which makes young people especially susceptible to drawing the
wrong (sometimes literally fatal) conclusions from events that they
experience, information they hear/read/see.

------
tallanvor
The author is cherry picking studies to try and prove his hypothesis, ignoring
that the "studies" he cites show only a possible correlation.

First, he's taking the results of a voluntary survey of users of his own site.
He'd be better off asking a polling firm to randomly contact people, ask if
they regularly read any more well-known sites that are more "intellectual" in
nature, and then ask about the person's birth order.

Second, he uses anecdotal data about Harvard students, which ignores several
potential sources of bias. As one example: Harvard is expensive, and students
are more likely to come from families with large incomes. High-income families
have fewer children. Another example: younger siblings often specifically
don't want to go to the same school as their older siblings, so if an older
sibling gets into Harvard, they are less likely to bother applying.

There's also a bit about males being more likely to be gay based on having
more older brothers. I could probably spend an hour listing reasons you
shouldn't take that research seriously.

~~~
naasking
> The author is cherry picking studies to try and prove his hypothesis,
> ignoring that the "studies" he cites show only a possible correlation

Not really, he starts out explaining that most previous research on birth
order effects was well and truly debunked. This doesn't disprove the existence
of birth order effects, and he makes a decent case.

> First, he's taking the results of a voluntary survey of users of his own
> site

And he thoroughly discusses the self-selection bias.

> Another example: younger siblings often specifically don't want to go to the
> same school as their older siblings, so if an older sibling gets into
> Harvard, they are less likely to bother applying.

If first-borns are more likely to go to Harvard, that's a birth order effect
too. If they're not more likely to go to Harvard, then Harvard should have an
even mix of birth orders and so aren't subject to the bias you point out.

------
torgoguys
For an effect this prevalent and strong my first reaction is "check your
data." Then I read this:

>It’s unlikely that age alone is driving these results. In sibships of two,
older siblings on average were only about one year older than younger
siblings.

And I really start thinking you have to check your data. The _average_ age
difference in that cohort is only one year and humans have a 9 month
gestation. Something is likely wrong with your data or your sample.

~~~
CarVac
He clarified in the comments

> No, the difference between the average age of all older siblings taking the
> survey, and the average age of all younger siblings taking the survey, was
> one year.

------
leoedin
I would be interested to know how only children fall into this analysis. If
the oldest child has more intellectual curiosity because they received more
attention, you'd expect only children to have received even more attention
still.

~~~
erfgh
Yeah but then you have nobody to compare with.

~~~
theptip
The average of the population? (In this case, the average SSC reader.)

If you have a big enough sample, you can ask if the average only child scores
higher "Openness" than the average reader, or if their self-reported IQ is
higher. That's a meaningful comparison I believe.

------
searealist
It's pretty likely that first born children were more likely to respond to the
survey given that Scott openly stated he expected more first born children to
be among his readership, giving people an impression that first born is better
and they might feel good about themselves vs second born children who might
feel bad about themselves.

~~~
Yvain
I don't remember mentioning that prominently before the survey. Can you link
me to the relevant quote?

~~~
searealist
[https://slatestarcodex.com/2017/12/25/preregistration-of-
hyp...](https://slatestarcodex.com/2017/12/25/preregistration-of-hypotheses-
for-the-ssc-survey/)

    
    
        7. I plan to confirm or disprove, once and for all,     
        whether our community has more older siblings. For lack 
        of a fancier way to do this, I’ll take the set of all 
        people who have exactly one sibling, and see what 
        percent of them are older vs. younger. If it’s 
        significantly above 50% older, I’m going to interpret 
        this as a birth order effect. I’ll do the same with the 
        set of people who have two siblings, three siblings, 
        etc, and combine them all for a final determination. 
        Half-siblings will be ignored. If you have any problems 
        with this methodology, tell me now.

~~~
Yvain
That post starts with "Please don’t read on until you’ve taken it, since this
could bias your results."

But I checked the data I received before and after I posted that, and the
birth order effects are about equally strong throughout.

~~~
darepublic
The prevalence of older siblings could be because of other reasons perhaps?
Only people born with a certain period of time are likely to be interested in
transhumanism and of those more are older siblings than otherwise.

~~~
losvedir
He explained that, too. The average age of all the older siblings that
responded and the the average age of all the younger siblings that responded
were within 1 year.

------
trgv
I thought it was conventional wisdom that sexual orientation in males is
influenced by birth order. If that's the case then I'd be surprised if there
were no other effects.

[https://en.wikipedia.org/wiki/Fraternal_birth_order_and_male...](https://en.wikipedia.org/wiki/Fraternal_birth_order_and_male_sexual_orientation)

~~~
Froyoh
Huh. First time hearing about this!

------
civilian
There's a handful of comments kind of getting tripped up here. Scott is
relying on a 1-2 punch-- First, that openness to experience was decently
different in the two groups (73rd percentile vs 69 percentile) and then that
most Big5 tests aren't done well. (

Big5 is a valid personality test-- it gets decent test/re-test scores, but
it's still weak. Myers-Briggs fails because, despite being very similar to the
Big5, it doesn't have good enough test/re-test scores.)

Scott cites another study that says when you test openness properly, you get a
wider distribution. So if you pair those two together, you get a decent sized
effect. Maybe.

------
stupidcar
This doesn't seem to be a "birth order" effect, so much as a "first born"
effect. Once you get past the first child, there doesn't seem to be much
influence. That makes me very skeptical of any biological explanation, as you
would expect to see more of a tail-off.

I think it's more likely a measurement error, or some subtle statistical
effect caused by a combination of probability skewing and demographic changes.

~~~
kstenerud
Or is it a physiological change that occurs in the mother after giving birth;
one that doesn't change much further on subsequent births? Death rates due to
complications after childbirth were quite high during 99.999% of our history.
It's not out of the question for there to be an evolutionary adaptation that
puts a little extra oomph into the firstborn in case the mother dies before
having a chance for a second, even if it caused a higher risk of death (due to
giving the embryo more of the mother's resources in vitro) to do so.

~~~
larrik
I have 2 boys, both adopted, and both biologically the youngest.

Yet, "oldest children are more conservative, youngest children are more
creative, etc." and the oldest being more intellectually curious describes
them _perfectly_.

So, anecdotally, my study of 1 data point says it's probably nuture and not
nature.

------
alkonaut
There is also a disproportionate amount of people online that are born jan 01
1900, and have mothers with the maiden name "asdf". Several thousand % more
than you would expect.

~~~
rocqua
As explained in other comments[1], being the eldest sibling wasn't the default
answer to a question. Instead, people were asked to enter into a text field
their number of older brothers, older sisters, younger brothers, younger
sisters.

[1]
[https://news.ycombinator.com/item?id=16105462](https://news.ycombinator.com/item?id=16105462)

------
utopkara
Reading a random person rant about scientifying stuff, should perhaps be
evenly distributed across siblings; until you realize that writing style does
give away a lot about the person writing it. You can write a decently
performing classifier that predicts gender (and several other demographics)
from stuff they write, even from tweets, and chats. It would be stupid to
think that people do not pick up the demographic clues in writing, and set
their preferences accordingly.

~~~
rocqua
Are you suggesting that the effect found could be explainedby first-borns
liking the style of the blog rather then the content?

~~~
asdfaefasdf
His writing indicates he believes his readers are "more intelligent", and he
believes that first borns are "more intelligent". So yeah, if you were a
second born, who was more intelligent, you'd dismiss his blog as BS, and would
not be counted among the survey respondents.

~~~
gjm11
For that to work, you (our hypothetical more-intelligent second-born) would
need to:

1\. Have seen Scott express the opinion that first-born children are more
intelligent.

2\. Interpreted that claim in a way incompatible with your own experience of
being an intelligent second-born (e.g., taken Scott to be saying first-borns
are _always_ more intelligent).

3\. Been sufficiently offended (or otherwise unimpressed) by this to stop
reading his blog when you would otherwise have been happy to read it.

For this to explain the apparent firstborn bias in Scott's survey respondents,
_thousands_ of potential readers would need to have done this. So, how
plausible is it?

1\. I've been reading Scott's blog for years and don't remember ever seeing
him say anything like "first-born children are more intelligent" before this
post we're discussing now. That doesn't mean he never did, and I'd be
extremely unsurprised to find that he did -- but it does suggest that if he
did it was easy to miss.

2\. The distinction between "on average firstborns have an IQ one point or so
higher than non-firstborns" and "firstborns are always smarter than not-
firstborns" is not exactly subtle.

3\. Well, anyone can get upset about anything, but this really doesn't seem to
me like the sort of thing that would make thousands of people swear off an
otherwise interesting blog in disgust.

I'm going to rate it _very implausible_. No way is anything remotely like this
a non-negligible fraction of the explanation for the apparent firstborn bias
in Scott's survey respondents.

------
nl
It's odd to discuss this without also mentioning the very strong apparent
affects of birth order on sporting ability, eg [1].

I'd never heard of the supposed higher intelligence of first born, but I've
heard a lot about the sporting side and anecdotally I've noticed it too (I am
the oldest sibling in my family).

[1]
[https://www.ncbi.nlm.nih.gov/pubmed/20435800](https://www.ncbi.nlm.nih.gov/pubmed/20435800)

------
rplnt
This doesn't seem like a valid approach to me. To take a specific group,
measure something, and assume that metric had an impact on them being in that
group.

It's interesting nevertheless.

~~~
hamandcheese
Well I think it’s fair to say that membership in the group didn’t impact the
participants birth order.

~~~
AstralStorm
It did. The data set is biased towards being older sibling about 3:1. If the
statistical distribution is fully shown then it could be some sort of an
argument.

~~~
AstralStorm
No idea about the downvote. This is a specific likely skewed sample. The study
has to be reproduced on general population.

~~~
xyzzyz
What do you mean by "reproduced on general population"? This is explicitly a
study of SSC readers. Obviously in general population you won't find that
oldest siblings outnumber younger siblings by 3:1.

------
chrisbrandow
The birth order effect is fascinating to me because my bias is to trust the
scientific consensus, but as a parent I see such obvious patterns in my
children and in the dozens of friends kids that I’ve watched over the years.

It’s hard to reconcile.

~~~
_red
Fully agreed, its uncanny when you see it in person.

It makes sense from a genetic perspective: Similar how to allocate investment
funds (primary funds in safe conservative investments, additional funds in
more speculative 'moonshot' investments).

------
belorn
> _But these demand strong effects of parenting on children’s later life
> outcomes, of exactly the sort that behavioral genetic studies consistently
> find not to exist_

Would like to hear more details to that claim. When ever I read about genetic
factors (For example on the topic of depression), I keep hearing that without
the environmental factors the genetic indicators loose their predictive power.
Genetic factors in behavioral science make a person more effected by
environmental factors, but alone the genetic factor tend to have no effect.

To take the explicit example in the article. Is there an measurable effect in
adult life that correlate to the amount parents focus and dedicate time to
them as child? In rats I have heard enough studies to show a very strong
correlation between stress in adult life and time that the rat got groomed as
young by the mother. Could it be so simple that parents spend a bit more
time/focus with the first child during the first few years, while the second
child receive a bit less since there is now two children and the parents are a
bit more experienced and feel more secure in parenting. While rats and humans
are not identical, it is a strong hint that "parenting style" might carry an
effect into adult life.

Source:
[https://www.gwern.net/docs/genetics/2016-plomin.pdf](https://www.gwern.net/docs/genetics/2016-plomin.pdf)

 _Although heritability estimates are significantly greater than 0%, they are
also significantly less than 100%. As noted earlier, heritability estimates
are substantial between 30% and 50%.... No traits are 100% heritable (e.g.,
Plomin, 1989; Turkheimer, 2000)._

~~~
tomp
Check out [1] - _Top 10 Replicated Findings From Behavioral Genetics_

In particular, "all psychological traits show significant and substantial
genetic influence" mostly contradicts your comment, also "the heritability of
intelligence increases throughout development" \- i.e. environmental factors
(parenting) matter when kids is young, but less so when they turn into adults.

[1]
[https://www.gwern.net/docs/genetics/2016-plomin.pdf](https://www.gwern.net/docs/genetics/2016-plomin.pdf)

~~~
belorn
from the abstract:

 _Finally, we note that 4 of the top 10 findings (Findings 2, 7, 8, and 9) are
about environmental influences rather than genetic influences. Via genetically
sensitive designs such as twin studies, behavioral genetics has revealed
almost as much about the environment as about genetics._

You have to elaborate a bit more if your claim is that this paper disprove
environmental influences.

A second key aspect from the abstract:

 _Most important, heritability does not imply immutability (Plominet al.,
2013)._

~~~
tomp
> You have to elaborate a bit more if your claim is that this paper disprove
> environmental influences.

Not at all, but I think it disproves this part:

> but alone the genetic factor tend to have no effect

~~~
belorn
I disagree. Take the immutability aspect highlighted. Without environmental
influences, how do you cause a change? Genes can technically change during
life, but I doubt thats what the study referees.

The idea that genes dictate outcomes in immutable ways is exactly what the
authors of this study disagree with.

To make a direct example on the study of a particular gene and depression. If
you take a person with this gene, they have (if i recall right) 6 times higher
risk factor for depression compared to other people, but only if they also
have had a child hood trauma. People with the gene and no such trauma has no
higher risk for depression than people without the gene and no trauma. The
gene has a environmental aspect to it.

Page 5: _For example, a heritability of nearly 100% implies that environmental
differences that exist in the population do not have an effect on a particular
phenotype assessed at a particular stage in development.

Title: Finding 2. No traits are 100% heritable. Although heritability
estimates are significantly greater than 0%, they are also significantly less
than 100%. As noted earlier, heritability estimates are substantial between
30% and 50%,_

The study is very clear here. Environmental influences are estimated to be
between 70% and 50%, and never as low as 0% for any single trait.

Further more on page 6: _Many others have noted that no traits are 100%
heritable (e.g., Plomin, 1989; Turkheimer, 2000)._

My original claim was that alone the genetic factor tend to have no effect,
ie, no genetic factor gives 100% heritability for a trait in behavioral
science. This study support this claim. I am sorry to say that either you read
the study wrong or you misinterpreted my comment.

~~~
tomp
Definitely misinterpreted your comment. My interpretation of "no effect" is
0%, not <100%. Looks like we're mostly in agreement.

------
ACow_Adonis
Speaking informally, but as a professional analyst here who is unfortunately
at a computer with no analysis tools setup :( but who has worked with his fair
share of social, survey and demographic information.

Check your data. My first gut-instinct on seeing data like that is not "Eureka
- i found a huge first-birth-order effect", but rather "huh...looks wrong, I
wonder why that is?".

What do I mean "looks wrong"? Keep in mind I have no real "pony in the race"
on first-born effects (although I admit I am one), but intuitively it "doesn't
look like real social data looks like".

The effect is too big. Its too loud. Its too constant. Its too nice. Something
else is driving it and its your job to find out what...

The first place I'd look is data quality. Have you proven your data got into
your final histogram data set right? I had problems with your csv opening it
in libre office...looks like it interpreted it as having some value migration
between the variable in whatever you did. Could be my computer, but in my
experience, if there's a problem with the csv, these kind of things correlate
with other mistakes.

The second place i'd look is survey design: was there a default option, are
people clicking through by default, are the response frequencies of other
variables lining up as would be expected (gender, birthdays, that kind of
thing). If not, why not?

If you've crossed and ticked all those, only after that would I start the
analysis...but again, a pattern and effect of that size and consistency is
something that you should default to needing explained in the data. Reach the
conclusion that its real only after you've eliminated everything else.

~~~
aetherson
It wasn't a default option (you were asked to enter into a text field your
number of older brothers, older sisters, younger brothers, younger sisters).

He can't cross-reference by gender very well because his audience is
overwhelmingly male, to the point where there's probably not a lot of
statistical significance in the female audience.

But yes, I think that these data are very open to an "impossibly hungry
judges" critique. If birth order effects were so very visible and so very
strong, why haven't we noticed them before?

~~~
alien_at_work
>If birth order effects were so very visible and so very strong, why haven't
we noticed them before?

I'm not sure where you're from but everyone I know (including a psychologist)
sees birth order effects as very real with noticable effect. Have you never
seen the stats of first borns being overrepresented in management, for
example? Am I misunderstanding what you mean by "haven't noticed them before"?

~~~
aetherson
As the article mentions in like the first couple of paragraphs, those results
haven't generally withstood replication.

But more so, the effects in the Slate Star Codex survey are _extremely_
strong. You'd expect that an effect that strong would be part of the common
wisdom, not something that has to be teased out in a psychological study.

~~~
dclowd9901
Well, to what you just mentioned, it -seems- to be a "common wisdom" that is
disregarded by scientific study. So, maybe this is a case where the study was
ill-designed, but everyone took it for granted?

~~~
aetherson
I don't think it is common wisdom. Like, look: which of your coworkers are
first-born? How many of them did you intuit that without explicitly asking?

~~~
AstralStorm
That depends on the field. The guesses can be very accurate based on ancillary
data like profession.

------
lumberjack
To me it seems most likely that it is entirely due to environmental/nurturing
reasons rather than some innate effect of being first out of their mother. For
example money for school can vary, and the parents attitude towards nurturing
thier children definitely does.

------
saycheese
Found the aggerate survey data:

[https://goo.gl/forms/8bmb7dwWyBtS5nDM2](https://goo.gl/forms/8bmb7dwWyBtS5nDM2)

And it is pretty obvious the sample is bias, though take a look to see for
yourself and comment if you notice anything too.

~~~
asdfaefasdf
1/3 of respondents are still in school. 2/3 of respondents have been reading
the blog for >1 year. 94% consider the blog "favorable"

Pretty skewed results.

~~~
gjm11
What do you mean by "skewed"?

Obviously the SSC readership is a very long way from being an unbiased sample
of (say) the whole world's population. No one would expect it to be, and in
fact that's _the point_ here: a survey of people who are obviously unusual in
some respects (whatever combination of quirks turns someone into a likely SSC
reader) turns out to be unusual in another respect with no obvious connection,
namely having substantially more firstborn children than you'd expect.

Whatever it is that makes someone more likely to read SSC, it seems like it's
probably a combination of things that surely can't correlate with birth order
(e.g., being a native English speaker) and, broadly speaking, personality
traits (e.g., being interested in the sort of thing Scott writes).

So the results show evidence of a link between birth order and personality,
and (from the survey results) apparently a strong one. Which is interesting if
true. And all of this only works _because_ the SSC readership is far from
typical of the population of a whole.

So, again, what do you mean by "skewed"? And why is it a problem?

------
godelski
Anyone else find it strange that the author used SAT scores as a metric for
intelligence? I think it is kind of absurd to think that a test that is
specifically not designed to test intelligence and designed to give trick or
misleading questions is a good metric. Not to say there isn't a decent
correlation between intelligence and test scores, but a significant amount of
people fall through the cracks. From what I understand, even the academic
communities don't place a lot of weight on tests like SAT, ACT, GRE, etc. I
think it is fine to use this method to measure intelligence, but not in
isolation.

~~~
dragonwriter
> Anyone else find it strange that the author used SAT scores as a metric for
> intelligence

Since SAT scores are very highly correlated with IQ test scores, and they are
often more available, no, not at all.

I'm much more concerned with how the sample (if it can even be called that)
was generated, which kind of makes the whole thing worthless. The pointers to
peer-reviewed studies (even though almost certainly cherry-picked) are more
useful than the original “research” reported.

~~~
savanaly
I'm confused what a "sample" group means in this context.

Take people who have one and only one sibling:

For the studied population (people who chose to take the SSC survey) the % of
people who were the older sibling was some number.

The "sample" to compare that to is...what? The human population as a whole?
Then we don't need a sample group, we know it has to be 50%.

So if the number he got in his study is much different from 50% that says
something about the population in the study being different.

------
mcguire
" _I first started thinking this at transhumanist meetups, when it would
occasionally come up that everyone there was an oldest child._ "

Alternative hypothesis: first-born children wish to escape their siblings so
much that they would prefer to leave the species.

~~~
AstralStorm
This is not what is being analysed and either conclusion is data dredging.

------
testplzignore
> It’s unlikely that age alone is driving these results. In sibships of two,
> older siblings on average were only about one year older than younger
> siblings. That can’t explain why one group reads this blog so much more
> often than the other.

It would be interesting to investigate the relationship between the age of the
respondent and the effect of birth order. For example, does birth order matter
less for millennials than it does for baby boomers, or vice versa?

Also would be interesting to investigate how much the age difference between
siblings matter. For example, does birth order matter more if the siblings are
born 1 year apart vs 10 years apart?

~~~
guelo
You can download the data if you want to do those analyses.

------
hamandcheese
Not an issue with this study, but possibly worth noting that, naturally, there
_must_ be more firstborns than subsequent-borns (not counting the generic
middle-child grouping). This could lead to a larger preceived effect.

~~~
kstenerud
Actually, it would be impossible for there to be more firstborns than
subsequent-borns (barring death) because siblings require 2+ people, of which
one and only one will be firstborn.

~~~
hamandcheese
For every second born, there must be a first born, but not vice versa. For
every third born, there must be a second born and a first born, but not vice
versa...

So you're more likely to encounter a first born in the real world than any nth
born, since some families will have only had one child.

------
losteverything
Few things helped me more understanding people and family than knowledge of
birth order.

First born, middle, baby, only... Quite helpful as how to understand and
predict people's actions. And how to communicate with them.

Also, the cases where the first born or first son being expected to behave
like a FB but are naturally not...often they dont realize this until
adulthood.

The book by Leman (The Birth Order Book) i bought shortly after entering the
workforce. A great read.

------
psynapse
For those interested in the topic, I can recommend Judith Rich Harris' superb
book, The Nurture Assumption[1].

It mostly deals with debunking common views on parent->child effects, but
includes some material on birth order effects.

[1] [https://jamesclear.com/book-summaries/nurture-
assumption](https://jamesclear.com/book-summaries/nurture-assumption)

------
KirinDave
> It’s unlikely that age alone is driving these results. In sibships of two,
> older siblings on average were only about one year older than younger
> siblings. That can’t explain why one group reads this blog so much more
> often than the other

So, uh... People understand that "average difference" is a miserable plan here
right?

------
Tepix
The reason is probably that the first child gets the most attention, right?

~~~
teamhappy
Could be one factor. I read a thing the other day that said something about
child birth triggering some sort of immune reaction in the mother's body. That
could mean that the second child is born under slightly less ideal conditions
or something like that.

------
doku
There are some articles on HN about boredom and creativity. Perhaps its just
that firstborn have more time alone. It'd be interesting to see age
differences vs creativity.

------
owens99
For me, the movie Gattaca perfectly captures the importance of nature vs
nurture. The equalizer is how one responds to adversity.

~~~
carlmr
Gattaca is feel-good-about-the-human-spirit fiction. I wouldn't use it as a
source.

------
workthrowaway27
Wow, I'm impressed that the average IQ of Scott's readership is so high (at
least if you use SAT as a proxy for IQ).

------
canjobear
Didn't he also run a control condition on Mechanical Turk? Why isn't that
analyzed here to show the effect?

------
ggggtez
Not convinced. What about the effect of selection bias? That done probably
accounts for the entire "study"

------
olympus
Sure they exist, but we don't want to talk about it. There is a strong
motivation to be able to say that everyone is created equal, regardless of how
uncontrollable factors affect you (birth order, height, race, gender). We
don't want to kill someone's motivation to study for college just because they
are a third child. But stereotypes exist for a reason. The hard part is
separating hatred-based stereotypes from the stereotypes based on observations
throughout history.

Regarding birth order, the "middle child" stereotype is prevalent in Western
society. Did the middle child stereotype spring from some sort of effort by
first-borns to keep their lower-ranked siblings in line (a la racism?)? I
doubt it. The middle child stereotype probably came from hundreds of years of
observations. It's a similar story for the first-born and last-born
stereotypes- they weren't created out of any prejudice, but probably from
hundreds of years of mothers chatting about their kids.

Like the article says, denying that the differences exist prevents us from
ever finding out why (because people won't do research on something that
doesn't exist). So let's acknowledge that some groups of people are different
than other groups, and then respectfully do research to figure out why. The
differences could be societal- perhaps first-borns are treated with more care
by their parents, or they could be biological- perhaps the hormonal changes in
a pregnant woman are different for each successive child, or they could be
something else entirely- I had many of the same teachers as my older sister,
and I often benefited from them having a pleasant experience with her, making
my time in class much easier.

But anyway, the first step is acknowleding that a difference exists, and that
you aren't somehow "birth order-ist" just because you acknowledge that first-
born kids often outscore lower order kids on many metrics.

~~~
nsomaru
> There is a strong motivation to be able to say that everyone is created
> equal, regardless of how uncontrollable factors affect you...

This, this, this, this, this!

People are not created equal at all! That should be obvious to anyone
evaluates the world in even a cursory manner. There are material, physical,
emotional and intellectual differences between any two individuals.

I have a (totally baseless and unvalidated) theory: If you accept that all
people are not equal you are presented with a curious metaphysical problem
when considered from a Western "Christian" perspective; why did God create
both paupers and princes?--i.e., why are some born into ridiculous wealth and
others crippling poverty? Eastern traditions handle this typically by some
appeal to "reincarnation" and/or "karma." You can't do this in the Western
view because everyone there is living to get into heaven, not escape samsara
(it's funny that in some views these are actually the same thing :)

In earlier times when I debated fundamentalists, the retort would be "each is
tested in his own way" or something along those lines. How entirely
unsatisfying, the game is rigged and we're all not starting from the same
position! For the modern, non-secular mind, it seems people would rather
maintain the fiction of equality than consider the fact that the world is a
profoundly un-equal place.

~~~
ajuc
> If you accept that all people are not equal you are presented with a curious
> metaphysical problem when considered from a Western "Christian" perspective;
> why did God create both paupers and princes?--i.e., why are some born into
> ridiculous wealth and others crippling poverty?

When I was still a catholic I "solved" this by assuming God put souls with
more capability to survive hardships in bodies that experience more hardships.
Basically the world is a level-scaling MMORPG :)

When I stopped being a catholic I just assumed there's nothing fair about
universe, it's just random, so there's nothing to explain.

The fact we don't have equal chances is obvious, even people saying otherways
usually know this deep down, they just won't admit it because ideology, so
they might say "people are equal, but society is keeping some of us down"
(clearly not the only factor - see psychological development problems), or
"people are equally talented at different things, some of us don't get to
realize these talents" \- which might be true, for general enough definition
of talent, but is quite unlikely (if nobody's supervising the distribution of
talents - how do you ensure everybody's got the same amount?). And even if
it's true - the definition has to be so general that in practice it doesn't
matter.

~~~
nsomaru
> When I was still a catholic I "solved" this by assuming God put souls with
> more capability to survive hardships in bodies that experience more
> hardships. Basically the world is a level-scaling MMORPG :)

Interestingly, if you an understand the synthesis of eastern metaphysical
concepts such as "maya" (illusion), "karma" (causation) and their logical
implications such as reincarnation, you arrive at a similar conclusion -- the
world is essentially a game (meant to be enjoyed, a journey, a sport to be
reveled in), which scales your instance based on your karma! There's
respawning too :)

Choose your own adventure!

Just thought I'd drop a book recommendation here: "The Monk and the
Philosopher" \- Jean-François Revel and Matthieu Ricard [0]. A much younger,
atheist, science-absolutionist (?-haha) me had his mind blown by this text. It
made me seriously question my world view (which would be later be shattered by
a friend with considerable philosophical talent). I do not currently identify
as a Buddhist, and I'm not sure how it would be received now, but it certainly
was useful in breaking a certain science-dogma in me.

edit: punctuation, book recommendation

[0] [https://www.amazon.com/Monk-Philosopher-Father-Discuss-
Meani...](https://www.amazon.com/Monk-Philosopher-Father-Discuss-
Meaning/dp/0805211039)

------
gaius
I’ve often thought that certain jobs should only be open to first borns. Jobs
with serious responsibilities.

------
molszanski
intellectual curiosity != slatestarcodex reader

~~~
civilian
why?

~~~
molszanski
Let me illustrate this through an analogy.

If the survey took place on a gun enthusiast website:

\- Fair claim: first borns are more likely to be gun enthusiasts

\- Far fetched claim: first borns have stronger personalities

~~~
Yvain
I agree with this, but the reason I'm focusing on intellectual curiosity was
that of all the traits measured in the survey, it was the one that did show a
significant effect of firstbornness, and it was also the only personality
trait with a significant effect of firstbornness in Rohrer's study.

I'm not just assuming it, I'm saying that two analyses showed it was the only
trait that mattered, and then it suffices to explain the current data.

~~~
molszanski
I don't disagree. Findings are definitely interesting, promising and worth
further investigation!

I preach cautiousness in the name of finding the objective truth. One should
be careful when testing a specific group of people.

------
gonational
Middle child here.

I didn’t like the methodology of this study, so I did my own little study, my
wife being the core respondent.

The results were astounding and the P value is off the charts (higher is
better in this case - trust me).

Conclusion: middle children are the best

~~~
thrav
Has this conclusion ever been called into question?

------
dvfjsdhgfv
This article is going to be flagged into oblivion into a few hours. We're not
discussing the relationship between biological and psychological traits on HN.

~~~
bildung
Alternative explanation: this article is just not good science. It:

* doesn't control whether the not-first-borns are outside the target demographic (too old or too young)

* doesn't look at children without siblings

* more importantly: is just a cross section, so no causal relationships can be gleaned from that

* also highly problematic: is self-selecting, with no discussion of the distribution of people _not_ participating. With a poll question like that that alone invalidates every result, as obviously it invites bias towards readers who deem themselves smarter than their siblings

* is not discussing, and controlling for, alternative explanations for the observed result

All in all the margin of error is almost certainly a multiple of the effect
size, thus rendering the results useless. Which they are anyway, because you
can only answer a question like the one given in the article with longitudinal
studies.

~~~
evanpw
Since birth order is immutable, what would you gain by a longitudinal study?
You still only get one data point per person.

~~~
bildung
Sure, birth order is immutable, but you would gain multiple data points for
"intellectual curiosity", which would be the point of the exercise.

------
buserror
Wierd, I'm the youngest of 6, and I'm acknowledged by the others as the
smartest of the lot, by quite a margin. "bloody little genius" has been my
nickname since I'm about 8 ;-)

~~~
jVinc
What's weird about that? On average men outrank woman in professional tennis,
that doesn't make it weird that Serena Williams would utterly destroy me and
most men on the courts 10 out 10 times.

Single points aren't anti-points to statistical effects. Now if you happened
to have a thousand friends that where also the youngest of 6 and happened to
test higher on IQ scores, that would be weird. For more than one reason.

~~~
buserror
Well it IS wierd, because you would assume than that 'eldest child' principle
would get at least linearly worse the more kids there are in a family... So I
must be particularly lucky, OR perhaps we don't really have good numbers for
the other end of the spectrum, regarding 'youngest child' general
performances?

Or, again, perhaps there is a large part of cultural bias ("eldest/heir" of
the family being _assumed_ as better) so given more attention/resources... And
that since I'm from a family with a single mother (who didn't have
time/inclination for that) I was spared that?

In any case, I think making up "exists and are strong" conclusions without
taking into account more parameters is simplistic at best...

~~~
igravious
> Well it IS wierd, because you would assume than that 'eldest child'
> principle would get at least linearly worse the more kids there are in a
> family

First. The word is _weird_.

Second. No, you would not assume that. Why would you assume that? You could
also with equal validity assume that something is present in the mother with
the first-born that is absent in all the rest. You could also assume the study
is hokum and missed something obvious.

Third. This “Single points aren't anti-points to statistical effects.” is
_exactly_ why it isn't weird. Even supposing there is some statistically
distributed effect you as a single point is a total non-issue. You are not
special. Do get back to me if you've three heads or something.

Fourth. To think it is weird suggests you are in fact not as smart as you
think you are. :)

Fifth. To continue arguing the point when it has been explained to you why you
are wrong is again indicative of not being as smart as you think you are. :)
:)

~~~
buserror
First. I love people who seems to associate spelling with intelligence and
take high pride it pointing out other people mistakes, without any knowledge
of how many languages they might be fluent in.

Second. Oops, no seconds here, First is usually enough for me to lose interest
in said people.

~~~
tortasaur
I think they pointed out the spelling error because it was made twice. I don't
see anywhere in their comment where they tied it to your intelligence.

~~~
igravious
Thank you. It was because it was made twice, not a slur on their intelligence,
I wouldn't do that.

------
JustSomeNobody
Anecdata.

My older brother was as smart as a box of rocks. Even given that, he was an
under achiever. He would couch surf and mooch off anyone. He would work a job
until the first pay check then quit. If there was ever a reason to be against
UBI, he was it. I would tell my mom he's like that first pancake that just
doesn't turn out right because you rushed.

I, on the other hand, became an engineer.

~~~
dragonwriter
I dunno, sounds to me like your brother is the kind of person whose need for
money a d resulting intermittent attachment to the labor forces drives down
efficiency and wages and, as such, is an argument _for_ UBI rather than
against it.

