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John Taves

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The conventional wisdom of demographers is fundamentally flawed.

In the conversation "Why do so many think that population growth is an important issue for the environment? Don't they know the facts of demographics?" Hans Rosling uses the "facts" of demography to argue we don't have to worry about population growth. Demographers have fundamental flaws in their thinking. In short, they are dead wrong.

Consider a belief that has these 2 characteristics: 1) believers average more than 2 children, and 2) they successfully pass along that belief to the next generation to at an average of at least 2 of those children. This belief will overpopulate the planet. Imagine that 99% of the population are non-believers, and 1% are believers. It would take many generations for the believers to rise to sufficient numbers so that demographers would notice them, but in the end, the birth rate will be determined by the believers.

This logic shows us flaws in the data collection and interpretation techniques that demographers use. Demographers must prove that these belief characteristics cannot exist if there is any hope that the downward trend of birth rates will continue and stay at or below an average of 2 children.

Their sampling techniques filter out beliefs that are passed to the next generation. This error means that if demographers tried to find groups that have beliefs that are not behaving according to the demographic transition predictions, they won't find them in their data.

Demographers use extrapolation techniques to predict future birth rates, but the logic dictates that they must find groups that are averaging the most children, and monitor their growth.

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  • Apr 23 2012: I think you make a good point.

    What you're saying is that while it may be true that "on average" people tend to have less children as they get more affluent, it doesn't mean that the population will eventually peak or even slow down.
    This is because it only takes one subgroup to buck the "average" behaviour and continue to keep having lots of children even as they grow more affluent and eventually that subgroup will become a majority, and then the "average" behaviour will be to have more children even if affluence increases.

    I think you've identified a fatal flaw. Well done.
    • Apr 23 2012: Yes, that is a correct interpretation of what I am trying to convey.

      I will add that I also reject the demographers conclusion that affluence causes a lower birth rate. I agree it seems to correlate to it, but correlation is not a mechanism. We certainly know one mechanism, and that mechanism is opposite of their correlation findings. Averaging more than two children causes our numbers to attempt to grow to infinity, and nature can only stop that growth by killing children. That is poverty. Averaging more then two, eventually causes poverty.

      Oh, and another thing. I will not say that the population will not eventually peak. It will peak regardless of how we behave. That is the nasty reality of being on a finite planet. Please also see http://www.ted.com/conversations/10955/the_conventional_wisdom_of_dem.html (oops, that is this conversation. I meant http://www.ted.com/conversations/10956/humans_have_almost_always_been.html).
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        Apr 26 2012: If I was to try and boil your hypothesis down to a lamens comedy routine.

        Basically, smart people stopped having random reproductive sex, and started family planning, about 50 years ago... So, while it has seemed like the population was leveling out and getting smarter... Underneath it all... Stupid people, who had previously been on the decline, were just bangin away, and indoctrinating their children with nonsense.

        Now... The population didn't rise as fast as expected, but a whole bunch of smart people, have been repopulated by stupid people... and now our population is going to explode, with no one left who knows enough science to save us?

        Poetic isn't it?
        • Apr 27 2012: I enjoy the humor. But I cannot help pointing out a flaw... I just can't hold back.

          Assuming the stupid smart thing is humor, then the flaw is to assume that the population will rise. If we average more than 2, we attempt to grow the population exponentially. Whether it grows or not is determined by the capacity of the environment to provide for the increase. We certainly might be able to be more efficient at getting our sustenance, but given that the planet is finite, we cannot be infinitely efficient, and thus there is a limit.

          This is not some minor point. The UN estimates for future populations predict a peak of maybe 9 billion. Many people mistakenly use this as some sort of proof that there is no long term population problem. The fact that the population will peak is not news worthy. It must peak given that this planet is finite. Will it peak because we comprehend we must manage the birth side of the equation so that the death side is not forced to stop the growth?
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        Apr 27 2012: Oh... I think we're going to get to 12 or 13 billion before we reallize that 10 was unsustainable, as people who've been living exclusively on corn syrup start dropping dead at 25. I don't think we're going to hit the peak because we saw it coming and reacted, certainly the believers, who are in the vast majority won't... they don't believe in reacting to stimulus, they don't believe in facts, or numbers, or experiments. They believe that god created humanity, and loves us more than anything else, so we should just have faith in him, and everything will be alright.

        It's not just stupid, it's actually willful ignorance, it's intentional... it's evil. They want to believe that everything they do is right, no matter how horrible the consequences of their actions are, it's psychopathic behavior, but non believers / smart people... aren't calling them out for it. We believe in post modernism, and moral relativism now, so everyone has a right to believe whatever they want, no matter how destructive it is.

        Anyone else reminded of the old expression "The greatest trick the devil ever pulled, was convincing the world he didn't exist". If there is any group of organizations, that is constantly intentionally manipulating children into a violent and unsustainable life, it's the various modern religious organizations... Yet we constantly tell ourselves "but they're mostly nice people, and they mean well"... Thus, in terms of sexual selection... They're kicking our ass, and now they run the show again.

        With them running the show there is absolutely no hope for humanity to move below 2 children per family... So... I would argue, that we're definately going to kill each other over resources, rather than peaking by choice, specifically because, we believe in love, god, and faith. The irony is delicious. Things are funny when they're true.
        • Apr 28 2012: I certainly agree that as the number of believers grows, it gets harder and harder to stop it. I am hoping to find people that comprehend that the only solution to prevent these beliefs is universal knowledge that a belief with these characteristics is morally wrong.

          However, note that in your writing you do not seem to use the same definition of believer that I defined above. Yours use of the word "believer" seems to cast a wider net. I want to make it clear that I do not intend to agree with that. I am sticking to the definition I provided and will not include smart/stupid, this religion or that religion.
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        May 5 2012: Just so you know, I didn't actually mean to suggest that people who believe in religion, are all stupid, or all reproducing in unsustainable numbers. When I joked about believers in this context, being stupid, I meant people who take their religious beliefs, like "go forth and multiply", so seriously, that they don't care if the belief is sustainable. They are a part of the wider net though, and I think the secular world, and other believers, need to call them on it.
        • May 7 2012: That was the clarification I was hoping you would make. It is excellent, thanks.

          I agree that everyone needs to understand it is wrong to average more than 2 children.

          Just to be clear, "everyone" is the same set of humans that understands murder is wrong.
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    May 8 2012: But demographers have never said that their projections are 100% accurate. That's not needed either.

    Stating that because 1% of a population of 7 billion may have a birth rate that deviates from projections, and that this is a huge problem for demography -- that's really a silly topic.

    Demographers have been mostly right about population trends. I don't see any reason why their sophisticated statistical techniques would suddenly become invalid because of some strange, opaque little theory about "1% believers".

    I still don't get the point. I'll just continue to read demographers' projections and take them as they are: projections with a high degree of certainty.


    I see a bit of a similarity between what the Climate Change community does: nobody can predict the future, but they can, with varying degrees of certainty, project what will happen. And they come to a consensus, offering a rather clear picture of the trends and threats.

    Demography is not calculating the elliptical track of a planet. It doesn't have to be. It's a ridiculous comparison.
    • May 9 2012: If an astronomer used the projection technique from the perspective that the Earth is the center of all orbits to predict where stars and planets will be, they would be totally capable of positioning a 100x telescope to track anything in the sky for the next several hours. They would be useless for anything more significant, like for example putting a person on the moon, or finding large objects on a collision course with Earth.

      Demographers are in an analogous situation. Their failure to comprehend the concept I describe here, has led to the conclusion that we only need to improve women's education and rights, and ensure access to birth control. The conclusion is that if we do that, the total fertility rate will come down and we will not suffer deaths due to over breeding (listen to the 2 TED talks referenced above). I totally agree that we need to do these things. The logic shown in this topic dictates that those actions are not sufficient to ensure we end deaths due to over breeding.

      In order to end deaths due to over breeding we must all comprehend that a belief with these characteristics is morally wrong, because that is the only way to ensure a belief with these characteristics cannot happen.

      It seems you missed this concept: "I have the right to have as many children as I want" is a belief that has these two conditions and nearly 100% of humans have this belief. I agree that this is a strange opaque theory, but only because you and many others are actively refusing to comprehend it. It is not about 1% believers, it is about 99.99999% of believers. 1% was simply an example number.
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    May 2 2012: I don't really understand what John Taves is saying.

    Demographers not only rely on abstract projections. They rely on hard data. Every 10 years or so, states count their population. Recently they did a massive census in India. Most countries have decadal censuses. Compare these data every 10 years and you have a trend, on which you can base a projection. Demographers fine-tune their projections based on new data and trends. They've been doing this for decades.

    When it comes to the idea of the "99% non-believers and the 1% believers", I don't see the point either: if we go from 9.5 billion in say the year 2075 to 6 billion in the year 2150, and then "the believers" pop-up and add a billion people in the year 2200, - then what's the big deal? By then we'll have plenty of technologies to cope with 7 billion people.

    Demography is sound: look at data, then compare and project. But again, maybe I simply haven't understood what the author is trying to say.

    PS: by the way, the demographic transition is not a "belief", it's a social phenomenon that simply happens. As people get wealthier and migrate to cities, their fertility rate drops - universally, everywhere. It's not belief, it's the logic of social and economic relations.
    • May 7 2012: If I watch stars moving in the night, I can spot a trend and make a projection. The planet moves n degrees in m minutes. I can project the position of the stars and planets using this technique. The accuracy depends on the goal. If you want to use the stars for navigation, it stinks. If you want to know where to look for Jupiter in a few hours, it is fine. You can improve the projection by fine-tuning based on the new data and trends. Almost everyone will ignore the point about the required accuracy and tell you that this technique is junk. The logic of this topic shows us that the projection techniques demographers use for predicting birth rates, is junk.

      As evidenced by the following points, you've shown that at least for you, the demographic transition is a belief.

      1) You demonstrated, by using the concept I showed above, that the demographic transition theory cannot predict birth rates in 2200. Yet, you do not conclude it is junk.

      2) Stopping at the year 2200 and using 99% is not proof there is no problem. It illustrates nothing. The correct logic to project this to forever, and recognize that a belief with these two characteristics is morally wrong. (note: that "I have the right to have as many children as I want" is a belief that has these two conditions and it has near 0% non-believers).

      3) You assumed that we will have plenty of technologies to cope with 7 billion in 2200. This is not a logical assumption. Humans have discovered wind, water, coal, oil, uranium through history as cheaper and cheaper sources of energy. Most people make the mistake of projecting this sequence into the future. This is, to put it bluntly, an idiotic projection. Each time we discover an energy source, like say oil, there is one less energy source to discover. I am not saying that we will not be able to cope with 7 billion, but I certainly will not assume it. Oil runs out.

      Using the projection technique so badly is justifying a belief. This is not science.
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        May 9 2012: 1) That's an odd interpretation of what he said.

        2) It is in no way logical to attempt to project the hypothetical "to forever." It's almost like you want a demographer to look through some crystal ball.

        3) You made the claim "Demographers...are dead wrong." and have made other strong claims throughout the thread. And all this is based on a hypothetical situation which in turn is founded on the assumption of a belief that is on no way supported by observation in the real world. But when an opposing point is made, you point out assumptions and "certainly will not assume it", even though it is actually supported by the observation of what is an amazing rate of advancement over the past 100 years? That is, to put it bluntly, an obscene double standard.

        If you are referring to this thread, then I agree that this is not science.
        • May 9 2012: Re. #1, this is not specific so I cannot respond.

          Re. #2, by projecting this hypothetical forward we learn what we must not do. Humans must not have a belief with these characteristics. We also learn that a projection of future birth rates that does not factor in this concept is mathematically wrong. The last paragraph I wrote in the topic could be interpreted as a demand that demographers look through some crystal ball. I intended it to say that if demographers want to predict future birth rates they must deal with this concept.

          Re #3. The belief "I have the right to have as many children as I want" is nearly universal. It certainly satisfies the second condition; it is passed along to the next generation flawlessly. The set of humans that have this belief have never averaged less than 2, thus this belief satisfies both conditions. In short "no way supported by observation" is a bad observation. Before we observe data we must first observe logic.
        • May 9 2012: I do not see the double standard you are describing. You will need to point out any assumptions that I have made that are not logically correct. I have pointed out assumptions, and interpretations of observations, that do not make sense.

          I suspect you are misinterpreting the concept that this topic describes. It does not state that these beliefs do exist, however, the belief "I have the right to have as many children as I want" does have these 2 characteristics. It does not state that these beliefs will always exist, or must always exist. It makes no predictions of the future.

          Notice that the statement "a belief with these 2 characteristics will overpopulate the planet" does not predict the future. Similarly, "If I point this loaded gun at this child's head, and pull the trigger, the child will die" does not predict whether the gun will be fired, but the statement is totally accurate. The statement tells us what we must not do.
  • Apr 30 2012: 'Believers' - it would be beneficial if there were a definition of what is meant by this term. My first thought was that it could refer to religious beliefs, but I have reread several times and sense that it is meaning belief in bearing large families;

    My husband and I have a large family, and that choice was made for personal reasons, but not due to religious beliefs. We have always been concerned with the global aspect of the environment and personal consumption of resources. Our family lived minimally. We never were large scale consumers. I'd actually propose that our large family consumed less than a family of 2 or 3 children where there may have been more income available for such things. Also, not one of our children wants to have a large family. So the 'characteristic' presented, in this instance, does not fit.

    In countries such as Mexico, women bear multiple children for religious reasons. A woman's status in this particular culture is raised when she has a large family. Also, machismo plays a role in the family culture. Changing this deeply embedded belief would be a cultural revolution. I agree that demographers need to focus on these cultural groups mindsets and trends in order to have a true predictor of future birth rates.

    I have twin daughters (20) who are currently using birth control. But for completely different reasons. Melinda Gates addressed valid concerns which need to be addressed globally. A woman's personal reasons for using birth control should never be the issue. Access is the issue.
    • Apr 30 2012: In this context, a believer is someone who has a belief that has the 2 characteristics described above. The particular belief does not matter, as long as it has those 2 characteristics we humans have a problem.

      For example, consider the belief "It is OK to have as many children as I want". If people that have this belief average more than 2 children, and pass this belief along to the next generation to an average of more than 2 children, then humans will suffer overpopulation.

      I assume it was not lost on this audience, and you, that you and almost everyone else on this planet believes "it is OK to have as many children as I want". Clearly it is passed along to every child. It does not matter if the belief is passed along by direct teaching, or passively like this one has been. This means that it has the 2nd characteristic. It also has the 1st characteristic too, because humans have always averaged more than 2.

      Demographers will point out that the birth rate is coming down, which is to say that they belief that this particular belief will not have the first characteristic someday. Unfortunately, they do not have proof that this will happen. They have a correlation that suggests it might happen. Even if the belief "I have the right to have as many children as I want" does indeed manage to lose the first characteristic someday, nothing stops a different belief from having those 2 characteristics.

      I agree that Melinda Gates brought up some very good issues. Access to birth control is certainly a requirement, but this logic points out that access is not sufficient.

      Notice that your own logic is the same as demographers. You pointed out how you had a lot (in the past) and your children will not (the future), but there is no guarantee commensurate with the potential harm. You also used "large" instead of "greater than 2". 2 is a magic number in this topic. It cannot be replaced with "large" and "small". Demographer make both of these mistakes.
  • Apr 24 2012: I would not be surprised if rather a lot of demographers do consider these sorts of things. It was probably a demographer who raised this issue in the first place. I didn't know demographers had 'conventional wisdom'; I thought they had statistics and hypotheses. We don't need demographers here anyway; the message is simple: all should have this freedom that I personally enjoy. I found this very interesting but I was waiting to see how you tied demography in with the actual topic, the argument presented. How is it you are saying the demography is at fault here? How is demography even pertinent, except if we want to quibble about a zero here or there? All we have to know - and we can see without graphs and tables - is that the many are for whatever reason wrongly denied what we take positively for granted. End of debate, demographers sorry for your time, refunds at the door.
    • Apr 25 2012: Demographers are at fault because they are the scientists that make the forecasts on birth rates. I have been unable to find any scientists that comprehend what I wrote and have found no evidence that they are doing anything but a pathetic extrapolation of birth rates. They sample and average birth rates, which is fundamentally flawed as shown above.

      A belief with these characteristics would be dreadful. We must not let this happen, and there have been zero demographers speaking out about ways to ensure this cannot happen.

      I do not understand your other comments. What freedom are you talking about? What does "all we have to know...." mean?
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    Apr 22 2012: Do you have a specific example of an error by demographers? How are they "dead wrong"?
    • Apr 23 2012: I reread my original posting, and it seems to me that I did provide an example.
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        Apr 26 2012: I reread your original post and it seems to me that you pawn off hypotheticals as examples. Also, your conclusion in the hypothetical is unfounded, confusing totals with ratios.

        You claim demographers are dead wrong. If they are dead wrong then a clear-cut example should be easy for you to come up with. Not some what-if scenario, but an actual claim made by demographers which you show to be wrong, or at least biased due to an obvious confounding factor.
        • Apr 27 2012: I don't follow your hypothetical example complaint. Please be specific.

          I thought that "Demographers use extrapolation techniques to predict future birth rates, but the logic dictates that they must find groups that are averaging the most children, and monitor their growth." is a clear-cut example. I have not been able to find any articles that state that some group has a belief with the two characteristics described above, or an article that proves it cannot exist.

          Hans Rosling's TED Talk referenced above, shows the audience how birth rates have come down as wealth has risen. This theory, the demographic transition theory, depends on extrapolation and totally ignores the possibility that this topic brings up.

          This concept is simply absent in demography. That makes their conclusions dead wrong.

          I would be thrilled to find a demographer that comprehends this concept. Please introduce me to them.
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        Apr 27 2012: I might have misread your example. I took the belief to be arbitrary with the assumed >2 birth rates to imply the spread of the belief. In this case, non-belief could have a higher birth rate which pushes a faster spread of non-belief. However, after re-reading the example a few times, I now think that you are defining the belief itself as the desire for >2 children. Is this correct? If so, then yes, the belief would spread in both total and ratio, hence population increase.

        I am not sure that this aspect is not already considered though. At least, it seems quite doable to include this aspect. There is an inverse relation between birth rate and education. It is hard to expect education to decrease when it is becoming more available. Similar information could also be used to gain an idea of the local/global change in the birth rate, i.e. is it accelerating or decelerating, and do other factors aid in predicting a deceleration of the birth rate?

        I can't speak on whether the demographers are considering said factors, but I do agree that they should, and I have also seen many flawed approaches supported by nothing more than "I passed stats in college!!"
        • Apr 27 2012: I think I see your initial confusion. It seems you get it now.

          Generally I think of these beliefs as having a blatant "god wants you to have more children" message in it, however, ultimately the message does not matter. If the effect of the message results in those two conditions, then this belief will overpopulate the planet. I agree that people with no beliefs in the birth related area could average more and do a better job of overpopulating.

          Demographers have concluded that we are not going to overpopulate the planet. When education, wealth, and women's rights exist, they see that birth rates drop. They take that correlation and conclude there is a mechanism that causes this drop. Their solution for high birth rates is to ensure we all have a good education and wealth and can freely choose how many children we want. (see the two TED talks).

          If I stated that the demographic transition theory is bogus because it is only a correlation, thus nothing ensures we will average less than two, demographers would point me to their pile of data that "proves" we do average less than two when their their variables are present. I won't make a dent in their thinking. This topic's logic shows where their logic is flawed, their extrapolation techniques are bogus, and directs them to change their data collection and data interpretation techniques.

          But, more importantly, I see no way to prove that a belief with these conditions cannot exist. I also see no great way to hunt down all those that have these beliefs and track their growth. If you think about how to prevent these beliefs, I am hoping you and everyone else that comes in contact with it, will conclude that the only way to prevent these beliefs, is with universal understanding that beliefs like that are immoral.

          I need noted experts to state that they agree with that last sentence.