

Children of older fathers have lower IQs - ksvs
http://www.guardian.co.uk/science/2009/mar/10/child-intelligence-older-fathers

======
hachiya
With an average difference of only _3_ IQ points that this study found, these
children appear to be missing out on little with regards to intelligence.

I would be more inclined to believe any differences in intelligence, if there
really are any, are due to the environment in which the child was raised,
rather than genetic advantages and disadvantages. In today's world, I would
guess that children born to 50 year old men are being born into a family where
the wife is not the father's first wife, and the father is not as likely to be
as dedicated a father as the younger fathers plan to be. This is a sweeping
generalization, but I would wager that for those 50 year-olds who are
remarried (once, twice, or more), by the fact that they did not care to keep
the family intact the first time (excluding cases where the wife died), these
men and their current wives would be less likely to provide a nurturing
environment compared to a young father.

A sweeping generalization, but my gut feeling, based on the likely fact that
many of those 50 year old fathers are remarried once, twice, or more,
indicating to me that they are not as good a father as the SOME of the 20 year
olds will be.

Also, statistics on society's accepted geniuses do not seem to show a
correlation between fathers' ages and the intelligence of the offspring.

Here is a list I have compiled. IQ scores may be disputed, but the
intelligence of these people generally are not.

Genius IQ Father's age

\------ -- ------------

Einstein about 160 31

Galileo 185 44

==========================================

Bobby Fischer 187 Likely father, Paul nemenyi: 48

    
    
                             Birth certificate father, Hans-Gerhardt Fischer: 35
    
                             http://www.nndb.com/people/455/000024383/
    

==========================================

Madame de Stael 180 33

Ludwig Wittgenstein 190 42

Blaise Pascal 195 35

Gottfried Wilhelm Leibniz 205 49

John Stuart Mill 200 33

Emanuel Swedenborg 205 34

Johann Wolfgang von Goethe 210 39

As you can see, one of the highest IQ's, Leibniz's, had a father who as 49
years old.

Einstein's, considered the lowest at 160, had a father of 31, the youngest in
this list.

So this is opposite the study's findings. However, I don't really see a
correlation overall.

With the study's difference of only 3 IQ points on average, I am inclined to
believe that age makes no difference in the intelligence of their offspring,
especially in those families that provide a nurturing environment, regardless
of the parents' ages.

~~~
katz
> I would be more inclined to believe any differences in intelligence, if
> there really are any, are due to the environment in which the child was
> raised, rather than genetic advantages and disadvantages.

Intelligence measured by the general intelligence factor is _highly_
heritable. The general intelligence factor is a factor analysis of
intelligence and is a measure of “innate” intelligence and attempts at
“boosting” this fails. The test that measures this the best is Raven's
progressive matrices which is culture and language negative. The general
intelligence factor is highly correlated with IQ and highly correlated with
future success. The performance of a person in these tests has to do with the
physical make-up of the brain (there are a lot of online articles by (dr/prof)
Haider that is fairly readable that sheds light on this subject.)

> Here is a list I have compiled. IQ scores may be disputed, but the
> intelligence of these people generally are not.

A note about your cited IQs – it is probably not correct. The popular press
like to “guesstimate” the IQ of historic persons – but this is of little
value. Rigorous intelligence tests (such as IQ tests) is a 20th century
phenomenon. Leibniz lived in the 17th century – well before these tests. So to
try and determine any IQ or measure of intelligence from him is a waste of
time.

Also – you collected only a point sample - I bet someone could get the same
example with selecting a different group of famous persons. You also only
selected the top 1% and not the general populations – so to draw assumptions
of this sample to the general population would be wrong.

I do agree with you that the study is somewhat worthless. Here are several
conflating factors:

People involved in menial labour (i.e. without tertiary qualifications)
generally get children at a younger age. A lot of older financially secure men
would generally marry younger less intelligent women (trade-up/Russian bride
phenomenon). The age of child bearing of different social classes differs
significantly.

Also - a three point IQ difference with all these conflating factors would
probably fall under the heading "not statistically significant".

~~~
tokenadult
_The test that measures this the best is Raven's progressive matrices which is
culture and language negative._

I've attended a lecture by John Raven, the publisher of that test, and he
doesn't make that claim.

The long, careful examination of what the Raven tests show, in conjunction
with other evidence, can be found in James R. Flynn's excellent book What Is
Intelligence?, which is about to come out in a new, expanded edition.

[http://www.amazon.com/What-Intelligence-Expanded-PB-
Beyond/d...](http://www.amazon.com/What-Intelligence-Expanded-PB-
Beyond/dp/0521741475/)

Also very good for reconsidering the importance of IQ tests is Keith
Stanovich's What Intelligence Tests Miss.

[http://yalepress.yale.edu/yupbooks/book.asp?isbn=97803001238...](http://yalepress.yale.edu/yupbooks/book.asp?isbn=9780300123852)

[http://www.amazon.com/What-Intelligence-Tests-Miss-
Psycholog...](http://www.amazon.com/What-Intelligence-Tests-Miss-
Psychology/dp/030012385X/)

~~~
katz
> I've attended a lecture by John Raven, the publisher of that test, and he
> doesn't make that claim.

I never said that he made that claim. Several other people compared RAPM and
other intelligence tests to determine the g-loading. It was found by other
people (not Dr. Raven) that RAPM has a high g loading. Testing for the general
intelligence factor and the use of RAPM is widely accepted. Here is an example
of a recent article: “Just one g: consistent results from three test
batteries”, (Wendy Johnson, Thomas Bouchard, etc...) 2004. Using Google
scholar you can find several other results. Even if you reject RAPM as a
measure of g, there are less g-loaded tests (such as IQ) that can be used that
predicts more or less the same thing (heritability of intelligence, etc...).

> The long, careful examination of what the Raven tests show, in conjunction
> with other evidence, can be found in James R. Flynn's excellent book What Is
> Intelligence?, which is about to come out in a new, expanded edition.

My problem with most of Flynn's books is that he is a political scientist and
a passionate left-wing campaigner. He is basically a Gould-light – distorting
science to fit his own world view.

I usually prefer to read papers or books on intelligence matters from people
with a PhD in areas such as educational psychology or neurology when it
concerns brain structure (e.g. prof. Haier).

~~~
tokenadult
_My problem with most of Flynn's books is that he is a political scientist and
a passionate left-wing campaigner. He is basically a Gould-light--distorting
science to fit his own world view._

There are a lot of Ph.D. psychologists who disagree with that statement. Here
is what Arthur Jensen said about Flynn quite a few years ago, and he hasn't
retracted this statment: "Now and then I am asked . . . who, in my opinion,
are the most respectable critics of my position on the race-IQ issue? The name
James R. Flynn is by far the first that comes to mind." Modgil, Sohan &
Modgil, Celia (Eds.) (1987) Arthur Jensen: Concensus and Controversy New York:
Falmer. Here's what Charles Murray (all right, not a psychologist nor a
geneticist) says in his back cover blurb for Flynn's book I mentioned in this
thread: "This book is a gold mine of pointers to interesting work, much of
which was new to me. All of us who wrestle with the extraordinarily difficult
questions about intelligence that Flynn discusses are in his debt." As
Mackintosh (1998, p. 104) writes about the data Flynn found: "the data are
surprising, demolish some long-cherished beliefs, and raise a number of other
interesting issues along the way." Flynn has earned the respect and praise of
any honest researcher who takes time to read the primary source literature.
Robert Sternberg, Ian Deary, Stephen Pinker, Stephen Ceci, Sir Michael Rutter,
and plenty of other eminent psychologists recommend Flynn's research.

As for what we can conclude about the Raven Progressive Matrices test, one
thing we certainly can't conclude is that it is not influenced by the cultural
background of the test-taker. The test publisher says culture matters in Raven
scores.

[http://www.eyeonsociety.co.uk/resources/RPMChangeAndStabilit...](http://www.eyeonsociety.co.uk/resources/RPMChangeAndStability.pdf)

~~~
katz
> are the most respectable critics of my position on the race-IQ issue?

The race-IQ issue is separate from the issue of general intelligence and
neuroscience of the brain. Even if he is a successful political scientist, it
would not make him an educational psychologist or neuroscientist. Much of the
popularity of Flynn is his opposition to certain views of Intelligence - not
his research.

> one thing we certainly can't conclude is that it is not influenced by the
> cultural background of the test-taker

With language and cultural negativeness I meant that there is no cultural
specific references. One of the main complaints of the IQ test was that it
contained western concepts and examples and language (i.e. it was culturally
loaded). For example – the pictures in RPM are the same and contains the same
meaning from whatever culture you are. Here is a quote from “How Biased are
Culture-Loaded Tests?” (Jensen, A):

> Probably the best known and most widely used of such tests s Raven's
> Progressive Matrices (citations). Such nonverbal tests are expressly
> designed to reduce item dependence on acquired knowledge and to keep
> cultural and scholastic content to a minimum while getting at basic
> processes of intellectual ability.

Also note that that study did not just use RPM but included a verbal section.

The study you gave me showed differences in RPM between what they labelled
“cultures” - other authors used other “labels” to try and explain the
difference between groups. Here is a quote from the study you gave me:

> On the one hand, the absence of cross-cultural differences in RPM scores
> between cultures which do differ on a variable

~~~
tokenadult
Thanks for the reply. My friendly response to the suggestion that I should
consider mostly what subject a person has earned a Ph.D. in as the basis for
whom to believe on what subject is that sometimes good ideas for one subject
come from people who learned another subject. Sometimes that's the best way to
make progress in a subject that has become stuck in outmoded theories. I
observe that Ph.D. psychologists

1) were taken by surprise by Flynn's research on IQ test score trends over
time, having initially predicted precisely the opposite trend,

2) proposed very stringent standards for acceptable data before believing the
trend was real (and Flynn credits Jensen, who has just the sort of credentials
you have recommended, as being especially tough in demanding certain kinds of
evidence),

3) reviewed his publications before allowing them to appear in the leading
journals in the field of psychology,

4) invited Flynn to attend major conferences written up in specialized
monographs with acknowledged experts in psychology,

[http://www.amazon.com/Nature-Intelligence-No-233-Novartis-
Fo...](http://www.amazon.com/Nature-Intelligence-No-233-Novartis-
Foundation/dp/0471494348)

5) praised his work in standard textbooks on human intelligence,

6) devoted whole monographs specifically to his findings,

<http://books.apa.org/books.cfm?id=431712A>

and generally accorded Flynn greater honor as a researcher on psychological
phenomena than most psychologists gain in a lifetime.

[http://www.cambridge.org/us/catalogue/catalogue.asp?isbn=978...](http://www.cambridge.org/us/catalogue/catalogue.asp?isbn=9780521741477)

Anyway, scientific issues aren't decided by credentials, but by data. Flynn
found and analyzed some very important data that caused a lot of psychologists
to reexamine their assumptions. John Raven takes care to write, "The results
surprise many psychologists. Eductive ability has turned out to be more easily
influenced by appropriate educational and developmental experience than
reproductive ability." In other words, what Jensen and others took as a
"culture fair," "g-loaded" IQ test turns out to reflect modifiable educational
experiences that children have or do not have.

~~~
katz
I agree with you that my comparison of Flynn with Gould was not entirely fair.
Flynn found the Flynn effect which is an important part. But a book by Flynn
is _not peer reviewed_ and may be influenced by his political views (he is
author of “How to Defend Humane Ideals: Substitutes for Objectivity” after
all).

> Anyway, scientific issues aren't decided by credentials, but by data.

This is true – but data in peer reviewed journals not books.

> In other words, what Jensen and others took as a "culture fair," "g-loaded"
> IQ test turns out to reflect modifiable educational experiences that
> children have or do not have.

The majority of psychologists believe that the g-factor is an innate and
immutable property. The g-factor correlates with reaction times, glucose
metallisation rate and is highly heritable. This indicates that the g-factor
most likely have a neurobiological basis (see articles by Haier for example).

In a recent article the g-factor also appeared in a battery of 42 tests
(Johnson,W Bouchard, TJ, “Just one g: consistent results form three test
batteries”). Here is a quote from the abstract:

> The concept of a general intelligence factor or g is controversial in
> psychology. Although the controversy swirls at many levels, one of the most
> important involves g's identification and measurement in a group of
> individuals. If g is actually predictive of a range of intellectual
> performances, the factor identified in one battery of mental ability tests
> should be closely related to that identified in another dissimilar
> aggregation of abilities. We addressed the extent to which this prediction
> was true using three mental ability batteries administered to a
> heterogeneous sample of 436 adults. Though the particular tasks used in the
> batteries reflected varying conceptions of the range of human intellectual
> performance, the g factors identified by the batteries were completely
> correlated (correlations were .99, .99, and 1.00). This provides further
> evidence for the existence of a higher-level g factor and suggests that its
> measurement is not dependent on the use of specific mental ability tasks.

~~~
tokenadult
A definitive reply to most of that outmoded thinking about g can be found in
Nisbet's new book,

[http://www.psychologicalscience.org/convention/program_detai...](http://www.psychologicalscience.org/convention/program_detail.cfm?abstract_id=15178)

or in Stanovich's.

[http://yalepress.yale.edu/yupbooks/book.asp?isbn=97803001238...](http://yalepress.yale.edu/yupbooks/book.asp?isbn=9780300123852)

Stanovich is very clear on the distinction between "intelligence" (he is a
mainstream psychologist in calling "intelligence" what I would simply call
"IQ") and "rationality," an aspect of human cognition hardly tapped at all by
most IQ tests. Stanovich comes at these issues from the framework of cognitive
science, which also informs much of current behavioral economics. He
previously wrote a textbook on understanding psychological research that has
gone through a number of editions.

~~~
katz
> A definitive reply to most of that outmoded thinking about g can be found in
> Nisbet's new book,

If you feel that these views are outmoded – give me peer reviewed research
articles (not books). I do not have immediate access to books and books are
not peer reviewed. The article that I referenced above was written in 2004 –
you can find more recent articles in Google Scholar if you want to. I did not
see that the above article (or any of the others) have been refuted. I doubt
that you can refute thousands of research articles (a lot of them recent) and
a discovery that is probably the hallmark of modern psychometrics with a
simple reference to a book (calling anything that you oppose “outmoded”).

> Stanovich is very clear on the distinction between "intelligence" (he is a
> mainstream psychologist in calling "intelligence" what I would simply call
> "IQ")

Also I think you are confusing “intelligence” with the general intelligence
factor (g) (also intelligence does not equal IQ. IQ is just a standardised
intelligence test that is fairly well correlated with the g factor). The
general intelligence factor is a factor that is common to almost all different
tests on intelligence. While the general intelligence factor is immutable
other parts of intelligence can be changed by training/learning (i.e. by the
environment).

> "intelligence" (he is a mainstream psychologist in calling "intelligence"
> what I would simply call "IQ") and "rationality," an aspect of human
> cognition hardly tapped

The purpose of intelligence tests is to test intelligence – not factors such
as rationality, emotion and inter-personal skills such as Stanovich's book
suggest. The latter are all factors that is undoubtedly environmental and the
value of such tests are doubtful to the intelligence debate.

------
ShabbyDoo
I wonder if the study controlled for the selection bias inherent in the
decisions of males of various ages to reproduce and in their preferences for
mates. Presumably, 50 year-old men are not procreating with women their age.
Do older men choose younger, but dumber women to mate with? Do dumber men end
up having children later in life? Are 50 year-old men worse parents?

~~~
latortuga
While I was reading this article I felt almost the exact same thing - the
whole article feels like bad science because they present the conclusion that
"many scientists believe that genetic mutations that build up in the sperm of
older men are to blame." Presumably, the only thing this study has shown is
that lower intelligence is correlated with older fathers but the cause could
be any number of factors like what you said or even, for example, that people
with lower intelligences are predisposed to postpone having children.

Basically, thanks Freakonomics for bringing correlation/causation to my mind
every time I read an article like this.

~~~
mhb
Correlation - xkcd

<http://xkcd.com/552/>

------
ChrisMac
As far as I know, a three point IQ difference doesn't have any practical
effect. It may be statistically significant, but it's hardly a huge advantage
to score three points higher than someone else.

------
sounddust
I have always wondered - when reading articles like this - whether it would
just be better to freeze one's sperm at age 20 and then save it for when you
want to have a child. In fact, it might even be better to save sperm from age
14 or so to reduce even further the chance of generic mutation.

I don't know if this is easy or even possible to do (or whether using frozen
sperm brings its own complications), but it's worth researching further.

~~~
whacked_new
I have wondered about this too, but I recall reading that sperm quality also
varies with the current bodily state. Maybe the end of high school would be
the best age. But it is a strange thought to have: you are essentially
depositing unborn babies into a bank, and retrieving them when you decide you
want them.

To take it further, you could freeze enough sperm for 100 conceptions, then
get a vasectomy. Which probably yields an even more efficient outcome, with
stranger connotations.

~~~
pavel_lishin
My stepfather has said a few times that he wishes he had taken the "further"
option.

I'm not sure if I ever want kids, but something about freezing my sperm and
getting a vasectomy worries me. A fire at the sperm bank, and my genetic
legacy is lost forever.

(Of course I could go in for a reversal, but those don't always take, etc.,
etc.)

------
cosmo7
Can we draft a law preventing journalists from trying to interpret statistics?

~~~
tokenadult
First let's teach college teachers of statistics (who usually aren't
statisticians) how to teach statistics. One of my favorite articles on that
subject

<http://statland.org/MAAFIXED.PDF>

is so thoughtful that I reread it from time to time just to savor the
language. Another good article about how to teach statistics

[http://repositories.cdlib.org/cgi/viewcontent.cgi?article=10...](http://repositories.cdlib.org/cgi/viewcontent.cgi?article=1002&context=uclastat/cts/tise)

is helpful in guiding people who have studied statistics before to rethink
what they think they have learned. It is by a very eminent statistician.

------
mhb
_The same study found that children's IQ was marginally higher if they were
born to older mothers, a finding scientists have put down to those women
spending more time caring for and nurturing their infants._

Maybe younger fathers are more nurturing.

------
tokenadult
It looks like several journalists need to read the new book Intelligence and
How to Get It by Richard E. Nisbett,

<http://www.wwnorton.com/catalog/winter09/006505.htm>

which I am reading just now. Nisbett reviews the best recent literature on IQ
testing and what it means, and punches holes in the fallacious reasoning used
by many advocates of a strong hereditarian view of influence on IQ.

A really good book for background reading on IQ testing and how it works is IQ
and Human Intelligence by N. J. Mackintosh,

[http://www.amazon.com/IQ-Human-Intelligence-N-
Mackintosh/dp/...](http://www.amazon.com/IQ-Human-Intelligence-N-
Mackintosh/dp/019852367X/)

which includes very clear explanations of how IQ tests have developed
historically, how they are currently constructed and validated, and what we
still don't know about human rationality despite a century of IQ testing.

------
vermontdevil
This is purely anecdotal but my grandfather was 60 when my dad was born. By
all accounts my dad was a highly intelligent man who achieved well in the Navy
despite not finishing high school (needed money).

~~~
huherto
On the anecdotal side. A friend was born when her father was 75. Some people
say she is a genius (clearly an exaggeration) but she s smart any way.

------
known
You are a product of your environment. --Clement Stone

