5 ms·

This study seems to base its conclusions for the most part on a study from 2016[0] and a study limited to Norway[1]. Both of these studies base their findings o

This study seems to base its conclusions for the most part on a study from 2016[0] and a study limited to Norway[1]. Both of these studies base their findings on data from 1995-2005 (with the exception of the Netherlands and Britain which both span larger periods) this data itself is collected from variety of experiments with varying sample size and testing methodologies. There certainly appears to be something interesting here, but I'd be hesitant to draw any conclusions from this data the way TFA does, which reeks a bit of sensationalism. At best I'd call it something worth investigating more thoroughly, at worst it's statistical noise. [0] https://www.gwern.net/docs/iq/2016-dutton.pdf https://www.gwern.net/docs/iq/2016-dutton.pdf [1] http://differentialclub.wdfiles.com/local--files/assigned-topics-iq/End%20of%20Flynn%20effect%202004.pdf http://differentialclub.wdfiles.com/local--files/assigned-to...

jandrese 7y ago
This is the kind of study where I expect in a few months to see headlines about IQ NOT dropping, and then more headlines about how IQ is dropping and in the end the whole thing is inconclusive. The more attention grabbing the headline is the more skeptical I am of the study.
- magicnubs 7y ago
  Hasn't it only "fallen" by something like 1 point? That seems like it may easily be due to some (potentially very hard to identify) confounder.
  - rocqua 7y ago
    If it fell 1 point per 10 years, but used to grow 3 points, that is a much stronger change than the bare number suggests. (My numbers are made up and unsourced)
wcunning 7y ago
I wish that I saw more of these comments on HN links to science articles that explain some research paper. From now on, every such comment that analyzes the underlying study's power and significance, I'm going to upvote, as a general policy.
rladd 7y ago
If it is in fact happening, perhaps carbon dioxide levels during pregnancy and early brain development are critical? We know that elevated CO2 is negatively correlated with cognitive scores: https://www.yaleclimateconnections.org/2016/07/indoor-co2-dumb-and-dumber/ https://www.yaleclimateconnections.org/2016/07/indoor-co2-du...
- phonypc 7y ago
  From your link: >"But a new Danish study failed to confirm these findings. The paper, published in February 2016 in the journal Building and Environment, reports no cognitive decline even when subjects breathed air containing 5,000 ppm carbon dioxide." >"Even scientists who have found an effect say more research is needed before they are convinced that modest amounts of carbon dioxide are a public health problem. Satish says that, so far, nobody even knows by what biological mechanism carbon dioxide might dim the brains of test subjects." I feel like people are way too readily accepting this CO2 cognitive decline thing. There are other comments here saying that we know CO2 causes cognitive decline.
stOneskull 7y ago
i see 'outrage culture' being a big part. instead of thinking and talking, it's easier to just say 'bigot-racist-homophobe'.
- tastygreenapple 7y ago
  Also, those most outraged are currently importing massive amounts of third worlders into developed countries. Mean IQ of a population decreases when millions of lower-IQ people enter that population.
  - stOneskull 7y ago
    the citizens in 1984 would have a lower IQ because of what they're allowed to think. and i see groups, whether they're left, right, whatever, like mirrors, each thinking their group is the 'good guys' and they maintain the party line even if it isn't their own thought. that cognitive dissonance leads to other IQ-lowering factors like medications and violence.
    - chillacy 7y ago
      IQ is a psychometric measurement and the best ones are "culture independent" like a bunch of matrix rotations or memorizing sequences of numbers. You can have a high IQ and still live in a political bubble (actually most of us probably do, regardless of IQ)
  - rfrey 7y ago
    Do you have evidence that economic migrants are lower IQ than people in more affluent countries?
    - RedComet 7y ago
      Just take a look at the average IQ of the countries that the migrants are coming from vs their destinations.
    - tastygreenapple 7y ago
trhway 7y ago
>Substantial gains in GA were apparent from the mid 1950s (test years) to the end 1960s–early 1970s, followed by a decreasing gain rate and a complete stop from the mid 1990s. [...] It is concluded that the Flynn effect may have come to an end in Norway. The single and/or the first children have higher IQ, so the Flynn effect is a reverse to the number of children per family, ie. it is a reverse to that graph: https://data.worldbank.org/indicator/SP.DYN.TFRT.IN?locations=NO https://data.worldbank.org/indicator/SP.DYN.TFRT.IN?location... And on the other side of the world - the "one child” policy results are in: "An increase of intelligence in China 1986–2012" https://www.sciencedirect.com/science/article/pii/S0160289613000901 https://www.sciencedirect.com/science/article/pii/S016028961... https://data.worldbank.org/indicator/SP.DYN.TFRT.IN?locations=CN https://data.worldbank.org/indicator/SP.DYN.TFRT.IN?location...
gingabriska 7y ago
So it's reversion to mean which is often seen in nature. If we see that today we don't really need high IQ to navigate our way through the cities, nation or even continent because we've GPS and other technologies which drastically reduce the amount of complexity we need to keep up with. Why should a higher IQ exist then? If we look at the past and see when and where the IQ increase took place, we see it increasing when when we were required to complex terrain and protect ourselves from harsh climate.

jandrese 7y ago

This is the kind of study where I expect in a few months to see headlines about IQ NOT dropping, and then more headlines about how IQ is dropping and in the end the whole thing is inconclusive. The more attention grabbing the headline is the more skeptical I am of the study.

magicnubs 7y ago
Hasn't it only "fallen" by something like 1 point? That seems like it may easily be due to some (potentially very hard to identify) confounder.
- rocqua 7y ago
  If it fell 1 point per 10 years, but used to grow 3 points, that is a much stronger change than the bare number suggests. (My numbers are made up and unsourced)

wcunning 7y ago

I wish that I saw more of these comments on HN links to science articles that explain some research paper. From now on, every such comment that analyzes the underlying study's power and significance, I'm going to upvote, as a general policy.

rladd 7y ago

If it is in fact happening, perhaps carbon dioxide levels during pregnancy and early brain development are critical? We know that elevated CO2 is negatively correlated with cognitive scores: https://www.yaleclimateconnections.org/2016/07/indoor-co2-dumb-and-dumber/ https://www.yaleclimateconnections.org/2016/07/indoor-co2-du...

phonypc 7y ago
From your link: >"But a new Danish study failed to confirm these findings. The paper, published in February 2016 in the journal Building and Environment, reports no cognitive decline even when subjects breathed air containing 5,000 ppm carbon dioxide." >"Even scientists who have found an effect say more research is needed before they are convinced that modest amounts of carbon dioxide are a public health problem. Satish says that, so far, nobody even knows by what biological mechanism carbon dioxide might dim the brains of test subjects." I feel like people are way too readily accepting this CO2 cognitive decline thing. There are other comments here saying that we know CO2 causes cognitive decline.

stOneskull 7y ago

i see 'outrage culture' being a big part. instead of thinking and talking, it's easier to just say 'bigot-racist-homophobe'.

tastygreenapple 7y ago
Also, those most outraged are currently importing massive amounts of third worlders into developed countries. Mean IQ of a population decreases when millions of lower-IQ people enter that population.
- stOneskull 7y ago
  the citizens in 1984 would have a lower IQ because of what they're allowed to think. and i see groups, whether they're left, right, whatever, like mirrors, each thinking their group is the 'good guys' and they maintain the party line even if it isn't their own thought. that cognitive dissonance leads to other IQ-lowering factors like medications and violence.
  - chillacy 7y ago
    IQ is a psychometric measurement and the best ones are "culture independent" like a bunch of matrix rotations or memorizing sequences of numbers. You can have a high IQ and still live in a political bubble (actually most of us probably do, regardless of IQ)
- rfrey 7y ago
  Do you have evidence that economic migrants are lower IQ than people in more affluent countries?
  - RedComet 7y ago
    Just take a look at the average IQ of the countries that the migrants are coming from vs their destinations.
  - tastygreenapple 7y ago

trhway 7y ago

>Substantial gains in GA were apparent from the mid 1950s (test years) to the end 1960s–early 1970s, followed by a decreasing gain rate and a complete stop from the mid 1990s. [...] It is concluded that the Flynn effect may have come to an end in Norway. The single and/or the first children have higher IQ, so the Flynn effect is a reverse to the number of children per family, ie. it is a reverse to that graph: https://data.worldbank.org/indicator/SP.DYN.TFRT.IN?locations=NO https://data.worldbank.org/indicator/SP.DYN.TFRT.IN?location... And on the other side of the world - the "one child” policy results are in: "An increase of intelligence in China 1986–2012" https://www.sciencedirect.com/science/article/pii/S0160289613000901 https://www.sciencedirect.com/science/article/pii/S016028961... https://data.worldbank.org/indicator/SP.DYN.TFRT.IN?locations=CN https://data.worldbank.org/indicator/SP.DYN.TFRT.IN?location...

gingabriska 7y ago

So it's reversion to mean which is often seen in nature. If we see that today we don't really need high IQ to navigate our way through the cities, nation or even continent because we've GPS and other technologies which drastically reduce the amount of complexity we need to keep up with. Why should a higher IQ exist then? If we look at the past and see when and where the IQ increase took place, we see it increasing when when we were required to complex terrain and protect ourselves from harsh climate.