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Predict civilization collapse with Python and World3 model
- AzzieElbab 5y agoCan I trade this for civilization prosperity in rust(optional)?
- tunesmith 5y agothis model is very sensitive to certain inputs if smidged a little bit yield vastly different projections. Models are more convincing when they are robust to that sort of thing. For instance go here: http://bit-player.org/extras/limits/ltg.html http://bit-player.org/extras/limits/ltg.html and try increasing the "output consumed (fraction)" input a little bit.
- mushufasa 5y agoNeat package. For reference, the field of looking at future civilization direction w/r/t climate change is called "Integrated Assessment Models," and DICE (from Nordhaus) is one of the most used and also open source https://williamnordhaus.com/dicerice-models https://williamnordhaus.com/dicerice-models . Here's the UNFCCC page on them. https://unfccc.int/topics/mitigation/workstreams/response-measures/integrated-assessment-models-iams-and-energy-environment-economy-e3-models#eq-1 https://unfccc.int/topics/mitigation/workstreams/response-me... . All models are wrong, some models are useful.
- teabee89 5y agoI would recommend reading/watching Steve Keen's critique of Nordhaus's work (e.g., https://www.youtube.com/watch?v=vwwvZ8g5eHE https://www.youtube.com/watch?v=vwwvZ8g5eHE). Steve Keen is the author of Debunking Economics.
- tomrod 5y agoSteve Keen is a name I haven't heard in a long time. From what I recall, he is pretty heavily critiqued, not in a "he might be right" sort of way, but more in a "totally misunderstands the basic philosophy underpinning what he critiques and sets up a strawman" kind of way.
- mushufasa 5y agoAfter reviewing the video, that seems fairly apt criticism.
- sideshowb 5y agoThe video seemed like a reasonable critique to me - what within it did you think was a strawman?
- mushufasa 5y agoThe critique is reasonable but it's a straw man -- Nordhaus is already well aware of the critiques he raised and has responded to them. My source: Nordhaus was my thesis advisor in 2016 and I wrote my thesis according to the same critiques Keen raised in this video, and Nordhaus responded to them... this video was from 2019.
- sideshowb 5y agoSo specifically what is Nordhaus' response to the criticism that a linear (or quadratic) model of gdp vs temperature fitted across space doesn't account for tipping points? Such as, say, if there is a severe scarcity of suitable land for growing food then the effort required to obtain food would likely rise in a very nonlinear fashion? (Not to mention that if that effort is reflected in price it could even show up as a positive in gdp when it's clearly a Very Bad Thing?) If the model described above is not what he actually did, then what is it he did do? Feel free to link your thesis if its the most succinct answer...
- mushufasa 5y agoHere's a speech nordhaus gave in 2009 on the topic. https://cowles.yale.edu/sites/default/files/files/pub/d16/d1686.pdf https://cowles.yale.edu/sites/default/files/files/pub/d16/d1... My thesis modeled the tipping points and extrapolated the damage function via monte carlo. Even in worst case scenarios the models didn't return overall damage functions that provoked the dismal theorem. Fundamental solow growth is too resilient (A = innovation). I didn't submit my thesis for publication so it's just in the university archives. Someday i'd like to revisit it with the latest science and another computational implementation and submit to publication. To be clear, I'm not saying Keen or Weitzman (Keen here is just parroting the late Weitzman) are wrong -- I'm partial to that intuition hence my thesis work. I'm just pointing out that this speech isn't really engaging with the latest literature on the subject meaningfully.
- truthwhisperer 5y agoinstead of peak oil this model suggests we are now in peak population? Funny Interesting package. Neat work
- ausbah 5y agomaybe it's referring to how the rate of change of population growth is decreasing?
- errcorrectcode 5y agoGlobal population stopped accelerating (had an inflection point, or: the "second derivative" went from a positive to a negative value) in the early 1960's. And so, overall population growth has been slowing ever since. It's difficult to say if or when population will reach a new, lower carrying capacity. It's curious that population growth peaked in most Axis countries before Allied ones in WW2. It would make sense if each country's values were more aligned with others in their faction.
- truthwhisperer 5y agoYes but on the other hand Hans Rosling described in this book/talks the world population will peak around 2100 with 11 billion people. The models seems to predict differently.. https://fs.blog/hans-rosling-population-growth/ https://fs.blog/hans-rosling-population-growth/
- dane-pgp 5y agoAnother inflection point could arguably be the year in which global fertility levels reach less than replacement level. Technically the global population can keep growing after that point, just by people living longer, but if life expectancy starts reverting to the mean then birth rates will have already past the threshold for decreasing global population. Here's what a recent Economist article says: "The world’s fertility rate, which stood at 3.5 births per woman in the mid-1980s, fell to just 2.4 in 2019. Indeed it is possible, given observed declines in rich-world births during the pandemic, that covid-19 may have pushed the world as a whole within sight of a replacement-level fertility rate, if only temporarily." https://www.economist.com/finance-and-economics/2021/12/11/why-the-demographic-transition-is-speeding-up https://www.economist.com/finance-and-economics/2021/12/11/w...
- doener 5y agoWatch this video to see what this is about: https://www.youtube.com/watch?v=kVOTPAxrrP4 https://www.youtube.com/watch?v=kVOTPAxrrP4 https://news.ycombinator.com/item?id=29525410 https://news.ycombinator.com/item?id=29525410
- giantg2 5y agoI think I'd rather be ignorant about this.
- xwdv 5y agotldr: Civilization should collapse some time around 2030.
- bencollier49 5y agoMore like 2015 from what I read in those graphs.
- xwdv 5y agoIs it possible than when civilization collapses we can only really realize it in hindsight? Kind of like how the only way to really know we went through a recession or depression is after the fact or at some point during it? Maybe we are already living in post-collapse.
- ncmncm 5y agoUS life expectancy has started down. That could be a consequence of absurdly inflated sugar intake (without adequate fiber) causing Metabolic Syndrome that causes a host of different acute, often enough fatal ills. But persuading Americans to ditch sugar and eat more fat will be a hard sell after so much propaganda against the has spilled.
- bart_spoon 5y agoOne (of the many) problems with predicting a societal collapse is the word itself, "collapse", being incredibly vague. What would define a collapse? For most it seems to conjure up visions of apocalyptic disasters. But it could potentially be a long, drawn out change to the trajectories of many metrics surrounding human population and economic activity. Who knows? I doubt we will even be able to define what a "collapse" is, let alone predict when that collapse might occur using modeling techniques.
- geoalchimista 5y agoNot sure I understand the reason this kind of model keeps getting spawned every few years. Idealized models with no relevance to empirical observations are nowhere near predicting civilization collapse. They can't even explain the observed past trajectories.
- jnurmine 5y agoDuring the 1970s the Club of Rome made "The Limits to Growth" with the World3 model and, whatever it predicts, some scenarios like the Business As Usual (BAU) seems to have tracked quite well for ca. 50 years already. The latest check-up is by Gaya Branderhorst in 2020, https://dash.harvard.edu/handle/1/37364868 https://dash.harvard.edu/handle/1/37364868. Of course, one has to understand that such a model doesn't show you "on the year 2028 the population is size 16.2931 billion". That is not the point. The point is to show how something grows, or shrinks, and the interrelations of the tracked variables. As x goes higher, y starts to diminish and soon after z goes through the roof, that kind of thing. The collapse of, for example, industrial output levels might be a form of a Seneca cliff. That is, the growth of the industrial output becomes harder and harder to achieve, while the difficulties compound and actually keep on growing long after the growth of industrial output itself has stagnated or started to drop slightly. This will dramatically increase the inhibitory effect, thus creating a growth curve which starts to slow down and then drops fast ("collapse"). Why dismiss the model? The BAU scenario seems to reflect reality for over 50 years now, so is it not rational to try to understand it? The Limits to Growth is fundamentally a realization that the world has finite resources. It is not illogical to consider this as a truth. At some point there won't be new resources to obtain, and hence growth in systems based on capturing resources will simply slow down (and perhaps even drop fast, "collapse", because difficulties compound). Circular economy and recycling are good but they cannot expand the available resource pool of e.g. raw materials.
- jshmrsn 5y agoI assume these are references to Isaac Asimov’s Foundation.
- shoo 5y ago
- Synaesthesia 5y agoSo an elementary model which cannot possibly hope to model all the real world variables is gonna predict the future? No no, this is too much but it's a cute toy, to play with models.
- actually_a_dog 5y agoUnfortunately, real world data since the 1970s matches up well with this "elementary model". See this comment: https://news.ycombinator.com/item?id=29535554 https://news.ycombinator.com/item?id=29535554 Do you have a more specific or substantive criticism of this work? Otherwise, I'd say it's essentially proven itself.
- bart_spoon 5y agoThe predictions from the model all match up in line with the parts of the model predicting an increase in various metrics, but the crux of the model, the inflection point and collapse, all have yet to occur yet. In other words, there would be nothing to prove that this model is any better or worse than a model that predicts these metrics continue to increase indefinitely.
- actually_a_dog 5y agoThe fact that there is good agreement between the model and real world data extending 40 years past its creation should, at least, raise your prior probability that the model is correct enough to be useful. If not, you're just being irrational.
- actually_a_dog 5y agoTo paraphrase Brahms when he first heard the Dvořák cello concerto: if I had known that it was possible to write a package like this, I would have tried it as well! I love this. It would be interesting to pair it with a decent climate model, though.
- lngnmn2 5y agoBullshit, bullshit everywhere. An abstract model can predict nothing, especially when the system is not fully observable, discrete, fully deterministic. Abstract modeling is the modern age astrology.
- betwixthewires 5y agoAs said above, no models are correct, some models are useful. I see the statement as akin (in some ways) to lies, damn lies and statistics, or the spherical cow. The models cannot predict the future. Too many charlatans have attempted to tell the public that they can, but they can't, and as a result people look for models that can, criteria by which they can trust models based on the credentials of their creators or the granularity of the source data, even reasonable implementation of the source data, but of course, no model can. But a model can teach you something about the mechanisms behind the interplay between different systems. It can tell you something general about the effects of certain situations. A good example of this can be seen in Lorenz's weather prediction models leading to the formal discipline of chaos theory. Often, algorithmic interaction between different values in models can lead to a discovery of a previously unknown mechanism by which something about the world can be gleaned, even if the model itself is useless at accurately predicting the future. But you're right, a model can predict nothing, and people need to bear that in mind, because pop science has people convinced that they should live their lives as if existing models can and do predict the future when in fact they do not.
- nl 5y agoCan we get the editorialising out of the title (currently: "Predict civilization collapse with Python and World3 model"). Putting aside the issues with the data etc, this model isn't even attempting to predict civilization collapse. The closest it comes is an attempt to model future population which isn't obviously correlated with level of civilization. The repo itself doesn't discuss "civilization" and it's unclear why the submitter thinks that is what it is doing.
- flenserboy 5y agoReminds me of an old Apple II MECC program from the early 80s called Limits. The user could "tune" various portions of the model and run projections as to when the world would reach its "limits" and collapse. Seems people have dug these sorts of automatic speculations for some time.
- ncmncm 5y agoIt may be instructive to compare individual health, where we have great experience with decline and collapse. Consider a physical activity that imposes a strain resulting in damage to tissue (muscle, tendon, cartilage, what-have-you) that heals fast enough not to accumulate. As you age, your rate of healing declines gradually. At exactly the point where rate of healing matches the rate of damage, you start into a sharp decline all out of proportion to any apparent, experienced event, as damage begins to accumulate at an unceasing rate. All contact-lens users hit such a point where their eyes seem "suddenly" to begin a rapid downslide if they do not abandon contacts. Many systems operating at global level have this character.
- deleted 5y ago[deleted]
- mclightning 5y agoRemember, Pessimist sounds smart but Optimist makes money.
- codeulike 5y agoprint('Goodbye world')