
Top Replicated Findings from Behavioral Genetics (2016) - erentz
http://journals.sagepub.com/doi/full/10.1177/1745691615617439
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groceryheist
While behavioral genetics is claiming victory in the replication crisis, it
should not rest on it's laurels. Replicability is a sign that studies can be
conducted consistently. However in the case of behavioral genetics, one fears
that all they have managed to do is reproduce and scale up erroneous research
designs.

Consider finding 3: "Heritability is caused by many genes of small effect"

This is exactly what you would expect to find if you do a regression with
1000s of variables: many effects, mostly small ones.

Of the 10 findings only 1 is clearly not a fact about statistics in settings
where dimensionality is very high relative to sample size.

Finding 5. The heritability of intelligence increases throughout development

Observe that this finding is based not on associations between particular
genes and traits, but instead on twin studies. Twin studies have their own
problems when it comes to causal identification.

That said, the overall claims here make sense and have some empirical support.
My point is that the field has long made outsized claims based on dubious
science that is legitimized by it's appropriation of genetics (even though it
is a branch of psychology, not biology).

Panofsky's book "Misbehaving Science: Controversy and the Development of
Behavior Genetics" is excellent.

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nonbel
I don't think this paper was even about replication.

A replication is when one person/group does something, they write down
instructions for someone else to do the same thing, and then the results are
compared. Is there a single mention of this happening in that paper? I
expected a table of such results.

Ie, replication is about doing some very specific thing, instead I see a bunch
of vague stuff like "abnormal is normal"...

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Xcelerate
Wow, I didn't realize so much progress had been made in behavioral genetics in
the last decade. Some of these findings are pretty mind-blowing.

The article mentions multivariate regression quite frequently—does anyone know
if more recent machine learning techniques have made their way into the field?

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groceryheist
| does anyone know if more recent machine learning techniques have made their
way into the field?

Oh god I hope not.

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svachalek
As someone with a background in neither genetics or psychology beyond a
layman's interest, this was surprisingly readable and informative.

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nurettin
The research starts off with citing stats against psychological research,
which I am fine with. What I don't understand is; how do governments and
private companies appear to have such an absolute grip on human behavior? They
can control your carreer, they can make you buy things you don't need, make
you sick without you being aware of it and place every complaint under the
labels of "fuss" and "conspiracy", those academics publishing unreplicatable
papers look like fools in comparison, despite being the actual cited experts.

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raihansaputra
because while governments and companies do it all the time, they don't really
know what exact part that they do is actually effective, while the academics
job is to dissect and explain what exactly works and why.

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danieltillett
Tweet sized: genes are everything, shared environment zero, and measurement
error the rest.

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jnordwick
From the paper:

> 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, typically between
> 30% and 50%, but this range of estimates is a long way from 100%.

Besides, some of the findings look significantly over generalized, and the
ones that aren't don't seem very revolutionary or intetesting.

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danieltillett
You are not going to be able to put this nuance in a tweet, but the major
problem with estimating the heritability of phycological factors is the error
bars are massive. You can’t even get near the same results when you measure
the same person on different days.

While there is obviously a non-shared environmental component, it is really
noise. The only factors that people care about are the factors that can be
studied; shared environment (that is all the environmental factors that can in
theory be measured) and genes. Non-shared environment is just what is left
over once you account for measurable environmental factors and genes.

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new299
If I've understood correctly, what you're saying is that there's really too
much noise is the results which can neither be explained by shared
environment, or genetics?

I've browsed the paper, but must of missed it. How big are the error bars? Is
it possible to get a sense of how much variation is explained by genetics
alone?

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danieltillett
There are three components to the variance: genetics, shared environment, and
non-shared environment (noise basically). Shared environment is almost
immeasurable for most of these traits (under 10%) while most is the variance
is due to genetics or non-shared environment. The way non-shared environment
is determined is by subtracting genetics and shared environment from the total
varience. The worse the test the bigger the component that ends up in the non-
shared environment factor.

The error bars depend on the trait being measured. Some are relatively small
(like g), while others like "agreeableness" (just choosing a random trait)
will be quite large as it is hard to measure this accurately and consistently.

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yters
If genetics determines behavior then we should be able to gene edit our way to
perfect virtue.

