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Peak Oil and Bayes' Theorem

General discussions of the systemic, societal and civilisational effects of depletion.

Re: Peak Oil and Bayes' Theorem

Unread postby entropyfails » Sat 24 Dec 2005, 16:51:10

$this->bbcode_second_pass_quote('Ludi', '
')I strongly disagree. Assigning meaningless numbers does nothing to increase our understanding. The number of neurotransmitters and activated neurons may have little to do with anything meaningful about emotions, such as the degree of discomfort I experience while reading and posting on PO.com.


I agree with your comment on meaningless numbers. Bayes’ Theorem helps us determine which numbers have meaning and which have no meaning.

Does that make sense?

And you know full well that the number of neurotransmitters has EVERYTHING to do with your mental state. Otherwise, what reason would you have to laud anti-anxiety medication? How do you think they found out if the medication had any merit? They used Bayes’ Theorem, that’s how. *grin*
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Re: Peak Oil and Bayes' Theorem

Unread postby Ludi » Sat 24 Dec 2005, 16:55:25

Dear me, this is difficult and takes us a bit OT.

The numbers do nothing to explain the quality of experience of the mental state.

Hmm. I wish I were a better communicator.

Suffice to say, you and I have a very different understanding of the universe. Not saying your way is wrong, just very different.

If I'm understanding you correctly, you say we can plug meaningless numbers into Bayes Theorem and it will tell us they are meaningless?

I'm sorry I'm such a dolt, but, there it is, we all know it.
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Re: Peak Oil and Bayes' Theorem

Unread postby entropyfails » Sat 24 Dec 2005, 17:04:44

$this->bbcode_second_pass_quote('Ludi', 'D')ear me, this is difficult and takes us a bit OT.

The numbers do nothing to explain the quality of experience of the mental state.
See, you use a rating system here, namely Quality of Experience. Now you may define it in a fuzzy manner “good”, “bad”, etc. but you can easily reduce that to a number as well using fuzzy logic.

$this->bbcode_second_pass_quote('Ludi', 'I')f I'm understanding you correctly, you say we can plug meaningless numbers into Bayes Theorem and it will tell us they are meaningless?
Exactly.

We have a whole system set up for it. We call it the scientific method. The meaningless numbers predict certain occurrences in reality. If they accurately predict reality, we say that a theory has merit. If they do not, we say it has no merit. We use Bayes’ Theorem to help us determine that merit.

$this->bbcode_second_pass_quote('Ludi', 'I')'m sorry I'm such a dolt, but, there it is, we all know it.
Don’t be so hard on yourself. *smile*
I blame the education system. *grin* Take a look at the link about Bayes’ Theorem in the post. I feel certain that if you study it, you’ll understand what I’m trying to get at.
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Re: Peak Oil and Bayes' Theorem

Unread postby Ludi » Sat 24 Dec 2005, 17:20:00

Ugh.

If we already know the numbers are meaningless, why do we need Bayes Theorem to tell us they are?

(my training is in art, not science - all the science junk I've had to pick up on my own)
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Re: Peak Oil and Bayes' Theorem

Unread postby entropyfails » Sat 24 Dec 2005, 17:38:29

$this->bbcode_second_pass_quote('Ludi', 'U')gh.
If we already know the numbers are meaningless, why do we need Bayes Theorem to tell us they are?

Well, from here we would have to delve into what we mean by “meaning.” *grin* All systems of symbolic transformation have no ultimate meaning, being computed reflections of reality. However, the do have “meaning” in that we can use them to build things that work in the real world. Or make predictions such as how long it will take an object to fall to the ground, or what probability we have of wiping out the ecosystem.

In that sense, they have “meaning.” Bayes’ Theorem tells us which theory accurately reflects reality and which theory has no bearing on reality. That seems like useful (i.e. meaningful) information to know. You may have the general feeling that constantly eating your home leads to ruin, but having numbers that prove it so makes it much easier to get people to change their minds.
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Re: Peak Oil and Bayes' Theorem

Unread postby Ludi » Sat 24 Dec 2005, 17:46:45

$this->bbcode_second_pass_quote('entropyfails', ' ')You may have the general feeling that constantly eating your home leads to ruin, but having numbers that prove it so makes it much easier to get people to change their minds.


Ok, I'm starting to understand.

Some of those numbers are available, now, how do we apply them?
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Re: Peak Oil and Bayes' Theorem

Unread postby entropyfails » Sat 24 Dec 2005, 18:12:00

$this->bbcode_second_pass_quote('Ludi', '')$this->bbcode_second_pass_quote('entropyfails', ' ')You may have the general feeling that constantly eating your home leads to ruin, but having numbers that prove it so makes it much easier to get people to change their minds.


Ok, I'm starting to understand.

Some of those numbers are available, now, how do we apply them?

Take a list of hypotheses and what you currently think the probability of each hypothesis should be.

Then take a list of predictions. For each hypothesis, calculate the probability of that prediction happening.

Then, get experimental data and if the hypothesis predicts the theory, raise its credibility. If it fails to predict the data, lower its credibility.

Let us take a quick example.

We have 2 hypotheses, Objects accelerate at most 9.8 meters per second per second when dropped on earth and Objects accelerate at most 1 meter per second per second when dropped on earth.

Now lets say I’m crazy and I think both are equally likely, ie the probability of it falling is 50% and the probability of it floating slowly down is 50%.

The falling hypothesis states the probability of dropping is 99.9% that it will fall at 9.8. The theory puts getting 9.7 at 95% and 9.6 at 90% (because it allows for experimental error and drag). It puts 11.0 at 0.1%. (ie our theory seems false if things fall much faster than 9.8 m/s^2)

The floating theory states that 99.9% of the time it will fall at 1 m/s^2 and 0.1% at any amount far above that (ie > 2).

I have no idea of which one better reflects reality, so I have to test it. I know about air resistance so I’ll choose a rock to drop and I get the following values.

9.6
9.8
9.7

After the 9.6 test, if you do the Bayes’ Theorem math, the probability of “fall” hypothesis becomes 98.9% and the probability of float becomes 1.1%. The experiment showed that the fall rate was beyond what the 1m/s^2 theory predicted.

The “junk number” has been ferreted out even after 1 trial. Then we take this 98.9% number and use it as the prior probability for the “fall” theory for the 9.8 and 9.7 numbers. Very quickly, the probably of the 1m/s^2 theory has gone far below 0.0001%.

Bayes’ Theorem has found the junk theory. Each additional datapoint reinforces the “fall” theory because it closely maps with reality, unlike the “float” theory.

Now our theories of civilization also make predictions with certain probabilities. Hence we can use Bayes’ Theorem to discern which one has more merit.
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Re: Peak Oil and Bayes' Theorem

Unread postby Ludi » Sat 24 Dec 2005, 18:15:42

I don't know how to turn the data into probabilities...

:?
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Re: Peak Oil and Bayes' Theorem

Unread postby Ludi » Sat 24 Dec 2005, 18:26:16

Sorry, I don't know how to do that....

Maybe you can do it. Here's some numbers:


•Our world population has grown more since 1950 than it has in the pre v i o u s four million years. With these additional people come additional demands on our earth: eighty perc e n t of the original rain forests have been c l e a red or degraded; one-third to one- half of the Eart h ’s land surface has been transformed.
•We lose one or more entire species of animal or plant life every 20 min- u t e s—some 27,000 species a year. This rate and scale of extinction has not o c c u rred in 65 million years.
•C u rre n t l y, 505 million people live in countries with water- s t ress or water- s c a rce conditions. By 2025, almost 48% of the Eart h ’s population–between 2.4 and 3.4 billion people–will be living in a reas of water stress or scarc i t y. This f reshwater shortage could intensify diff i- culties in meeting human consumption levels, and wreak devastating effects on our delicately balanced ecosystems.
•Only 0.3% of the planet’s water is available for human use. Due to
mismanagement, over 40% of the g roundwater in the U.S. is contaminat- ed by industrial, agricultural, and household pollution,making it e x t remely difficult and costly to purify.
•It takes 23 times more water to pro d u c e 1 ton of beef than it does to produce 1 ton of grain. Only about 2.5 billion people could be fed on a diet compara- ble to a developed country diet, in which approximately 35% of calories a re derived from animal sourc e s .
•Americans are only 5% of the world’s population, yet we consume 25% of the world’s re s o u rces. Resulting social and environmental problems re v e r b e r- ate around the world.
•Six million acres of prime farm- l a n d—an area the size of Ve rm o n t —w e re lost in the United States alone between 1982 and 1992. Four of those six million acres were usurped by urban and suburban expansion. The other 2 million acres were lost t h rough erosion caused by defore s t a- tion, unsustainable farming practices, and animal over-grazing.
•While the number of people living in 58 US metropolitan areas rose 80%
between 1950 and 1990, the land cov- e red by those areas expanded 305%.
•One U.S. citizen consumes about 30 times as much as a citizen of India. If e v e ryone on earth lived like the average N o rth American, it would re q u i re four m o re earths to provide all the material and energ y.
•Although the U.S. accounts for less than 5% of the world’s overall popula- tion, we produce 25% of all gre e n- house-gas emissions. In 50 years the U.S. will add 114 million people and Africa an additional 1.2 billion. Yet, it’s expected that the carbon emission for the U.S.’s 114 million will be the same as for Africa’s 1.2 billion.


http://www.populationconnection.org/Com ... 202002.pdf
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Re: Peak Oil and Bayes' Theorem

Unread postby bobcousins » Sat 24 Dec 2005, 19:08:07

$this->bbcode_second_pass_quote('MonteQuest', 'A')nd just what is your contribution here, besides just another ad hominem attack that does nothing to address the merits of the debate?


I think he has a novel and interesting approach, I would like to give it a fair hearing instead of dismissing it out of hand. Perhaps you could use your knowledge and intellect to help him refine the approach? After all, we are supposed to be exploring issues are we not?

Whenever someone suggests civilisation might continue, you throw up your hands and say "infinite growth, bah, impossible! End of discussion". Clearly infinite growth is impossible, and no one is suggesting it is. How does introducing that strawman help to explore anything? You just use it stifle further discussion. I guess you are uncomfortable with real debate lest it challenge your preconceived mindset.

Of course, it is you that are Senior Moderator, not me. Does "moderating discussion" mean anything to you? Do you not feel some tiny obligation to encourage discussion? Instead, as soon as a discussion starts to veer from your own viewpoint, you stomp on it. There is no chance to let people build a consensus. You stamp your authority on it. Everyone thinking of posting is warned, back off, Monte does not approve, this does not follow the official line.

$this->bbcode_second_pass_quote('', 'W')e are not doomed, we just can no longer continue on the same path of unsustainable nonsense.


That is just tautology, unsustainable means "cannot be continued". I have yet to see you explain how we are not doomed, you keep saying die-off is inevitable, and I have yet to see you explain what this sustainable civilisation looks like, one that cannot use any refined metals because apparently that is impossible without fossil fuels.

You are a stuck record Monte, and it is getting very boring. I just don't expect anything intelligent or positive from you any more. Move this to the Hall of Flames if you like, like the other posts that challenge you to accept that, just possibly, you don't know everything.
Last edited by bobcousins on Sat 24 Dec 2005, 19:20:05, edited 1 time in total.
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Re: Peak Oil and Bayes' Theorem

Unread postby smiley » Sat 24 Dec 2005, 19:13:26

I like the effort Entropy, but I fear that Bayer's theorem would not be practical in this case. In order to use these kinds of theories you need to define your triggers in extremely clear and verifiable terms.

The term large blackout is subject to interpretation. How many megawatts is a large blackout? Will you be inclined to rate a blackout in the west higher than one somewhere else due to the press coverage?

Then you have to have a good dataset. Such a dataset should include the entire world, since it is no given that the effects will start everywhere simultaneously.

I experienced several blackouts affecting a few million people in Cuba. None of them were recorded by the international press. So your dataset is already missing one of the countries which is most prone to blackouts.

You have to be extremely careful not to let the human judgment into the equation. I think the subject is too ambiguous to avoid that. Then you shouldn't embark on these kind of studies. You'll end up like the scientist who tried to verify the existence of God using these methods, and came to probabilities ranging from 1% to 99% depending on their personal conviction.
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Re: Peak Oil and Bayes' Theorem

Unread postby rockdoc123 » Sat 24 Dec 2005, 19:35:16

Wow....probably one of the best threads to be started here in my opinion. I am a huge fan of Baysian theory.....pretty much every projection I make for my field of endeavour is based on Monte Carlo or similar approach. I think this is a huge challenge however....as stated earlier pretty much everything can be expressed by a mathmatical equation or numbers can be applied to everything....that being said it requires a huge database of numbers to add any statistical validation to the results...as well....we have the old "unknown variable" issue. There are so many variables already in this equation that I think it is probably better handled with chaos theory....but not being a maths person I won't go there.
This is a worthwhile approach..but make sure you identify independent versus dependent variables....it makes a huge difference in the result. Just my tuppence worth.
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Re: Peak Oil and Bayes' Theorem

Unread postby smiley » Sat 24 Dec 2005, 20:15:09

I agree with rockdock that the amount of variables are going to pose a problem.

perhaps we should try something simpler.

There are a great number of predictions for the oil production: WOCAP Campbell, EIA, DOE, World Bank etc. Perhaps this methodology can be used to rate these models.

I mean you're just talking about one parameter oil production vs time, which is something which is verifyable and undisputable.

just an idea.
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Re: Peak Oil and Bayes' Theorem

Unread postby entropyfails » Sun 25 Dec 2005, 21:58:27

$this->bbcode_second_pass_quote('smiley', 'I') like the effort Entropy, but I fear that Bayer's theorem would not be practical in this case. In order to use these kinds of theories you need to define your triggers in extremely clear and verifiable terms.

The term large blackout is subject to interpretation. How many megawatts is a large blackout? Will you be inclined to rate a blackout in the west higher than one somewhere else due to the press coverage?


Yeah, that ends up being the rub of a lot of the arguments around here. We should try to find a way of unambiguously determining what constitutes evidence. If we cannot even agree on the evidence, then we really can say nothing about which theory has validity. By trying to find a consensus on what constitutes evidence and using Bayesian analysis, maybe we can make some progress here instead of running around in circles.

EUP seems like a fairly neutral metric that we all agree on. Taking public power use and dividing it by published population numbers should allow us to see of the 0.67% decline in EUP. I’ve seen EUP numbers up to the year 2000 but I haven’t seen much published on what has happened over the past 5 years. Does anyone have that data?

As for the 2012 blackouts, we can say that seems pretty unambiguous as well. Either we see them in at least 75% or so of large energy consuming countries or we don’t see them. Olduvai theory predicts them to be country wide issues with different causes in each country. (Though it predicts the underlying EUP decline as the root cause) Of course, if it comes to pass we won’t be able to get on this site to discuss it. *grin*

For the ever increasing country blackouts until the world event in 2012, I agree that we need to find a good system for measuring them. Does anyone know of a database of blackout numbers by country? As for the reporting issue, I think we actually see more reports from the East than we do in the west at this point. But the papers have strategic reasons for their reporting and culling the data from news reports could lead to the evidence wars problem discussed above. Can anyone help out with this? I’ll be posting to this thread when I find gems online.

And as we add theories, such as expounding upon Ludi’s predictions and finding a general ecological theory that covers collapse, we’ll need to find somewhat rigorous ways of determining evidence for these theories as well. If we can find no consensus way of doing this, we won’t have much to say about any theory of collapse and we’ll be back to the flame war mentality. At a minimum, we can say that if someone has posted a theory without trying to be specific about predictions and data analysis they obviously don’t want to inform people but convert them. From most of the post around here, I’d say we all want to avoid that.


$this->bbcode_second_pass_quote('smiley', 'T')hen you have to have a good dataset. Such a dataset should include the entire world, since it is no given that the effects will start everywhere simultaneously.

I experienced several blackouts affecting a few million people in Cuba. None of them were recorded by the international press. So your dataset is already missing one of the countries which is most prone to blackouts.


Well I have read about them in the alternative media, so some reporting has taken place. Again, we need to find a good database on blackouts by country. We have enough people from enough countries to do a regional analysis if we get volunteers to compile this data. We obviously do not all have doctorates, though some do around here. We obviously don’t count as a peer reviewed journal, but we can mimic their methods and thus have more confidence in the theories we see floated around here.

I agree with you that taking this approach means work. Hopefully we will get enough people interested in the science behind peoples visions of the future to enable us to determine what has happened and will happen to our world. Maybe this will end up being too large of a project for PeakOil.com, but that would not bode well for the usefulness of this site.

$this->bbcode_second_pass_quote('smiley', 'Y')ou have to be extremely careful not to let the human judgment into the equation. I think the subject is too ambiguous to avoid that. Then you shouldn't embark on these kind of studies. You'll end up like the scientist who tried to verify the existence of God using these methods, and came to probabilities ranging from 1% to 99% depending on their personal conviction.


If this particular problem goes beyond human capabilities, then this discussion will have no merit. I don’t feel as certain as you about this, however. I think that given a bit of training and setup, we can come up with a system for processing and understanding this information. Several of the metrics in these theories such as EUP have a fairly solid definition and can be presented with little to no controversy. Hopefully we can find enough of these datapoints and predictions in order to make sense of the data. If not, we’ll just have to enjoy the ride.

Regardless, making the effort seems like the most reasonable approach at this point.
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Re: Peak Oil and Bayes' Theorem

Unread postby Ludi » Sun 25 Dec 2005, 22:08:10

How do we apply that data to Bayes Theorem? I mean the numbers I posted above?
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Re: Peak Oil and Bayes' Theorem

Unread postby entropyfails » Sun 25 Dec 2005, 22:18:48

$this->bbcode_second_pass_quote('rockdoc123', 'W')ow....probably one of the best threads to be started here in my opinion. I am a huge fan of Baysian theory.....pretty much every projection I make for my field of endeavour is based on Monte Carlo or similar approach. I think this is a huge challenge however....

Thanks!

And I agree. It would be a huge challenge for this site. In fact, that serves as the basis for my post. I want to determine if enough people around here actually want to find out the truth or if this seemingly important discussion doesn’t matter to even a critical minimum. From this thread, you can see that it will require some education of the methodology of science, finding datamining experts, consolidating the data, and testing the hypothesis and running Bayes’ Theorem to determine the likelihood of our hypothesis set.

If we cannot do this, then I’ll have to do it personally on a much rougher basis which pretty much reduces this place to another area to mine data from. That may end up being the case. This thread serves as my litmus test.
$this->bbcode_second_pass_quote('rockdoc123', 'a')s stated earlier pretty much everything can be expressed by a mathmatical equation or numbers can be applied to everything....that being said it requires a huge database of numbers to add any statistical validation to the results...as well....we have the old "unknown variable" issue. There are so many variables already in this equation that I think it is probably better handled with chaos theory....but not being a maths person I won't go there.

I agree. I would like to see a collapse theory that uses chaos theory style math. Perhaps if we get enough interest in furthering this method, we can come up with one that we can put to the test.

As for the data requirements, this will take a lot of work as you point out. If we can identify the major theories that we see here and figure out which variables we need to track, then perhaps we can get volunteers to help assemble the data. I know I’d be one of them. *grin*
$this->bbcode_second_pass_quote('rockdoc123', 'T')his is a worthwhile approach..but make sure you identify independent versus dependent variables....it makes a huge difference in the result. Just my tuppence worth.

Identifying good variables does serve as one of the hardest parts of any science. We want to cut down on the complexity of the world, but if we do it in a poor manner, we end up with nonsense. We can always have a theory of “everything” that predicts ANY experimental result with a 99.9% probability. Obviously Bayes’ Theorem will rate that theory highly as it predicts everything. But it has no real use to us because it doesn’t limit any possibilities and hence makes for a poor scientific theory. But we do have enough doctors and science types to spot those from a mile away, I hope.

Thanks for your input!
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Re: Peak Oil and Bayes' Theorem

Unread postby entropyfails » Sun 25 Dec 2005, 22:58:17

$this->bbcode_second_pass_quote('Ludi', 'H')ow do we apply that data to Bayes Theorem? I mean the numbers I posted above?


Hey Ludi!

Don't worry, I was getting to it. *grin*
Let us take an example from what you posted.

$this->bbcode_second_pass_quote('', 'C') u rre n t l y, 505 million people live in countries with water- s t ress or water- s c a rce conditions. By 2025, almost 48% of the Eart h ’s population–between 2.4 and 3.4 billion people–will be living in a reas of water stress or scarc i t y. This f reshwater shortage could intensify diff i- culties in meeting human consumption levels, and wreak devastating effects on our delicately balanced ecosystems.


Olduvai theory states that we will not have the energy to process the salt water and distribute it. It falls well within the 95% confidence band put beyond the 2012 date. Unfortunately, Olduvai theory says little about population pressures so we don’t know if it will predict that even 3 billion people will exist by 2025. Stated this way, water scarcity has a dependency on population growth but the theory says little about population growth itself. Hence, we need to present a paired dataset of population numbers and water scarcity probabilities. So in this example we have

People in 2025 | Probability of Scarcity in half the population
7 billion 95%
5 billion 90%
4 billion 80%
3 billion 50%
2 billion 20%

Now Civilization Theory predicts that everything will work itself out as “the market” will provide that water for them via desalination, technology, etc. Civilization Theory’s probability of that failing seems very small. Unfortunately they don’t give numbers, so we’ll have to invent some for them until the time we can get a proponent of that theory to unambiguously define their probabilities. However, it does not allow for a large drop in population absent the external factor mentioned at the start of the thread, so we do not need to link it to the population numbers. To not care for half the population would be in opposition to the idea of ever increasing standards of living, but Civilization Theory allows for outside events to “thwart the progress of civilization” so we should probably place it less than 50%. A 30% number probably accurately reflects what Civilization Theory proponents feel will be the case. Again, since Civilization Theory has scant science behind it, we have some limits in applying Bayes’ Theorem. But this comes from them not making specific claims. Hopefully they will join in and make some claims.

Probability of Scarcity in half the population in 2025 = 30%

Now since we already have a test in 2012 for the worldwide blackout, the further 2025 test will probably not be needed. What we need is a theory that straddles the middle ground. Perhaps we should call this Ecological and Systemic Collapse Theory. This seems to state that as biodiversity decreases and humans go further into overshoot, all available resources will become more and more scant with each passing year. This theory bridges the gap in that it predicts water scarcity to increase each passing year by population growth rates. (in essence, the paper you presented takes that view) The authors of this study put the median at 2.9 billion in water stress and they also assume an increasing population up to this point as well. You can usually assume a 95% confidence in any published scientific paper unless they specifically state otherwise.

Probability of Scarcity in half the population = 95%

This theory goes further than the other 2 in that it predicts a gradual increasing of water scarcity by 2% per year. Hence we will be able to test the theory with Bayesian analysis by finding the scarcity statistic (probably provided by the UN) each year and testing to see if it went up by 1.5 - 2%. If it did, then we have an incremental confirmation of that theory and we will increase its probability. If it doesn’t, we can decrease the probability. The amount depends on exactly how much margin for error in scarcity numbers they tolerate and which years it predicts the worst scarcity increases to happen. We’ll need to build out this theory on this thread.

Near term predictions have more value to us because we cannot “run an experiment” like we can in a lab. Hence we should gear our choice of predictions to those in the 2006-2012 range. After that, we’ll know if Olduvai theory has merit (and then we cannot post about it here anyway) *grin* If we still are on this site in 2012, then we take some of the longer predictions of Civilization Theory and Ecological and Systemic Collapse Theory and test them.

Does that make sense?
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Re: Peak Oil and Bayes' Theorem

Unread postby entropyfails » Sun 25 Dec 2005, 23:01:18

$this->bbcode_second_pass_quote('smiley', 'I') agree with rockdock that the amount of variables are going to pose a problem.

perhaps we should try something simpler.

There are a great number of predictions for the oil production: WOCAP Campbell, EIA, DOE, World Bank etc. Perhaps this methodology can be used to rate these models.

I mean you're just talking about one parameter oil production vs time, which is something which is verifyable and undisputable.

just an idea.


Great Idea!

Most of these have been moving targets, however. *grin* But let's date their theories (ie ASPO_dec_2005) and put together a database of their predictions. (or just a table on this site). Then each year we can test them to see which model has more validity and who comes up with the more reliable models.

Did you just volunteer yourself for that project? *laugh*
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Re: Peak Oil and Bayes' Theorem

Unread postby Andrew_S » Mon 26 Dec 2005, 04:46:55

Bayes’ Theorem is used to update a conditional probability distribution in the light of new data. So it deals with random variables, for example A and B and their interdependence. You seem to be taking two mutually incompatible hypotheses (Olduvai and Civilization) and treating them as if they are random variables (which they are not: they are hypotheses).

To put it another way, on the real number line let Olduvai be called 1.0 and let Civilization be called 0.0. You seem to be trying to estimate the relative merits of the two mutually incompatible hypotheses as if there exists a continuous parameter from 0.0 to 1.0 which can be estimated. However, as stated 0.0 and 1.0 represent two incompatible hypotheses, i.e. nothing in between.

Another way of putting it, you have defined what's characteristic of Civilization and what of Olduvai. You could just as easily say, oh things are 0.5% Olduvai-ish this week, I'm not really a fan of that hypothesis. Then if a year later things are 95% Olduvai-ish you could say yeah there's a lot to be said for Olduvai. No need for Bayes' theorem there. Bayes' works in retrospect, it doesn't predict.

A parameterization of the problem is what you really want. Some knowledge of how the parameter(s) determine the outcome (Olduvai or Civilization) and a means to estimate the parameter(s) and their time course might provide a means to test the relative merits of the hypotheses.

I like the idea of some sort of rigorous testing, though.
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Re: Peak Oil and Bayes' Theorem

Unread postby seldom_seen » Mon 26 Dec 2005, 06:28:13

I like the idea of what you're doing, but it seems that applying a mathematical formula for calculating probabilities to whether industrial civilization will go on as is (civilization theory) or collapse (olduvai theory) is the equivalent to say filling up your gas tank, driving around all day long and using Bayes theorem to determine whether you will run out of gas or not.

The answer is already deducible through scientific method. There's is a %100 chance for the 'run out of gas theory' based on the continual drawdown of a finite amount of gas in your tank.

As MQ pointed out there is a 0.00% future probability for civilization theory. The planet is finite and industrial civilization requires the constant intake of raw materials for endless growth. Therefore, industrial civilization will at some point be stopped in its tracks. This isn't debateable in a scientific context. It's only debateable, or questionable if you haven't grasped the concept that we live in a finite world.

The only undetermined factor is time.
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