It's of course correct that rejecting a hypothesis at the 5% level doesn't mean that there is a 95% confidence in the alternative. However, in the case of global warming, we really only have two options (natural, not-natural/anthropogenic). If we can reject with 95% confidence that more than 50% of the observed warming was natural, then we can say that it is extremely unlikely that more than 50% of the observed warming was natural. Is it then strictly correct to say that it is extremely likely that more than 50% of the warming was anthropogenic? Maybe from a strictly statistical perspective this is wrong, but given that there isn't an alternative in reality, it's hard to see how it's all that misleading (i.e., if we're very confident that nature can't be responsible for more than 50% of the observed warming, then we can be pretty confident that more than 50% of it is anthropogenic/man-made).
What's P(H) for the target problem, doc, and how would you represent "The consistency of observed and modeled changes across the climate system, including warming of the atmosphere and ocean, sea level rise, ocean acidification and changes in the water cycle, the cryosphere and climate extremes points to a large-scale warming resulting primarily from anthropogenic increases in GHG concentrations"?
It only takes one scientist to solve a problem. I think the most interesting development on this issue came up on Tallbloke’s Talkshop and the Mensa Debating Forum. So what is the probability that man-made warming was ‘zero percent’ if the ‘Climate Change’ problem was solved in 1871 by James Clerk Maxwell when he mentioned the Poisson curve for gravity in ‘Theory of Heat (1871)’. The same curve used by Ned Nikolov & Karl Zeller in the ‘Unified Theory of Climate (2011)’ for the ‘Pressure-induced Thermal Inertia Greenhouse Effect’ on the surface of Venus, Earth, Mars, Europa, Titan and Triton. And then what is the probability for the repeated coincidence that the average temperature at the one bar pressure points on each of the planets, is the same, adjusted for distance from the Sun, despite the different main gases, Nitrogen for the Earth & Titan, Hydrogen for Jupiter, Neptune, Saturn & Uranus and Carbon Dioxide for Venus, which is also located on the Poisson curve for gravity. Gravity causes the Pressure. Does this produce a probability that Climate Change is 100% natural. From the Tallbloke website. The most important lesson in Climate science you are ever likely to watch: https://tallbloke.wordpress.com/2021/09/06/ned-nikolov-demystifying-the-atmospheric-greenhouse-effect
A must-read op-ed in the WSJ has the eye-opening headline “Covid censorship proved to be deadly.” I added my own thoughts on this superlative, important and profoundly-true essay. The link to the WSJ article is available in the Reader Comments if you can’t access the pay-walled version.
What the author (and I) are really saving is that Norman's writing - if it had been seen by many more people - could have saved countless lives and prevented misery of an epic scale.
Your coin example is excellent and accurately represents the current state of The ScienceTM.
Evidently, if you want to find out if a coin is double headed, you don't toss it five times. You simply take it and look at both faces. It doesn't require knowing the Bayes' theorem, or a prior probability, and provides an unequivocal answer.
Using models to estimate if the Earth is warming, and if the culprits are us, is as stupid as tossing a coin five times to estimate if a coin is double-headed.
Of course, with the coin, there is an absolutely correct and scientific way to test the hypothesis. With the anthropogenic climate change, there is no scientific way of estimating the human contribution. The uncertainty is too high.
A 2009 survey by Peter Doran found 97.4% publishing scientists agreed humans influence temperature, 2010 Bill Anderegg found 97% among most active publishing scientists agreed that humans caused warming and endorsed by organisations from 80 countries
Hello, I don't think the 2013 consensus paper has been debunked by the article that you link. The non relevant papers were rejected from the 21 years of scientific papers and in those remaining there was a 97% consensus. Three other studies also found majority agreement. The question as to what degree has human activity changed the climate was not really relevant as it is virtually impossible to assess as so many factors such as solar, pollution, volcanoes and el nino and la nino affect warming. We only need to know if humans are affecting climate even if only in a small way (as we in a period of solar cooling and la Nina even a little warming means a lot of anthropogenic warming), on which there is consensus, yes humans affect the climate. Unless you survey non-climate scientists and manage to get 0.3% of them to sign a headline grabbing Petition Project rejecting the consensus.
Whether the stats on the 95% that more than half of climate change is human made are flawed or not doesn't change anything either as I have shown above. The proportion of climate change at this point is not relevant and is difficult to assess.
You haven't debunked anthropogenic climate change in any way shape or form. Just maybe educated some as to what stats and claims of percentages can and can't show.
Professor Fenton, painstakingly helping the world to understand statistical legerdemain, one inquiring mind at a time.
Thanks for another helpful and informative exposition, Professor. The learning curves can be awfully steep, and a bit of guidance is greatly appreciated.
I remember seeing a photograph of a weather station in the middle of a field of grass and a subsequent photograph of it in a parking lot next to a building built long after the first photograph was taken. Same data acquisition point in a radically modified environment, producing just the long term temperature tread that the IPCC thrives on.
That’s melted my brain!!! Not being a mathematician or statistician I had to read that a couple of times! In my course language the IPCC and their scientists are bullshitting the world with their scaremongering!!!
A Climate expert that did not go along with the narrative.
https://youtu.be/7LVSrTZDopM
It's of course correct that rejecting a hypothesis at the 5% level doesn't mean that there is a 95% confidence in the alternative. However, in the case of global warming, we really only have two options (natural, not-natural/anthropogenic). If we can reject with 95% confidence that more than 50% of the observed warming was natural, then we can say that it is extremely unlikely that more than 50% of the observed warming was natural. Is it then strictly correct to say that it is extremely likely that more than 50% of the warming was anthropogenic? Maybe from a strictly statistical perspective this is wrong, but given that there isn't an alternative in reality, it's hard to see how it's all that misleading (i.e., if we're very confident that nature can't be responsible for more than 50% of the observed warming, then we can be pretty confident that more than 50% of it is anthropogenic/man-made).
What's P(H) for the target problem, doc, and how would you represent "The consistency of observed and modeled changes across the climate system, including warming of the atmosphere and ocean, sea level rise, ocean acidification and changes in the water cycle, the cryosphere and climate extremes points to a large-scale warming resulting primarily from anthropogenic increases in GHG concentrations"?
Nicely written!
It only takes one scientist to solve a problem. I think the most interesting development on this issue came up on Tallbloke’s Talkshop and the Mensa Debating Forum. So what is the probability that man-made warming was ‘zero percent’ if the ‘Climate Change’ problem was solved in 1871 by James Clerk Maxwell when he mentioned the Poisson curve for gravity in ‘Theory of Heat (1871)’. The same curve used by Ned Nikolov & Karl Zeller in the ‘Unified Theory of Climate (2011)’ for the ‘Pressure-induced Thermal Inertia Greenhouse Effect’ on the surface of Venus, Earth, Mars, Europa, Titan and Triton. And then what is the probability for the repeated coincidence that the average temperature at the one bar pressure points on each of the planets, is the same, adjusted for distance from the Sun, despite the different main gases, Nitrogen for the Earth & Titan, Hydrogen for Jupiter, Neptune, Saturn & Uranus and Carbon Dioxide for Venus, which is also located on the Poisson curve for gravity. Gravity causes the Pressure. Does this produce a probability that Climate Change is 100% natural. From the Tallbloke website. The most important lesson in Climate science you are ever likely to watch: https://tallbloke.wordpress.com/2021/09/06/ned-nikolov-demystifying-the-atmospheric-greenhouse-effect
A must-read op-ed in the WSJ has the eye-opening headline “Covid censorship proved to be deadly.” I added my own thoughts on this superlative, important and profoundly-true essay. The link to the WSJ article is available in the Reader Comments if you can’t access the pay-walled version.
What the author (and I) are really saving is that Norman's writing - if it had been seen by many more people - could have saved countless lives and prevented misery of an epic scale.
https://billricejr.substack.com/p/covid-censorship-proved-to-be-deadly?
Thanks Sir. That blew my simple mind's fuse! But 2nd read was better!
Your coin example is excellent and accurately represents the current state of The ScienceTM.
Evidently, if you want to find out if a coin is double headed, you don't toss it five times. You simply take it and look at both faces. It doesn't require knowing the Bayes' theorem, or a prior probability, and provides an unequivocal answer.
Using models to estimate if the Earth is warming, and if the culprits are us, is as stupid as tossing a coin five times to estimate if a coin is double-headed.
Of course, with the coin, there is an absolutely correct and scientific way to test the hypothesis. With the anthropogenic climate change, there is no scientific way of estimating the human contribution. The uncertainty is too high.
A 2009 survey by Peter Doran found 97.4% publishing scientists agreed humans influence temperature, 2010 Bill Anderegg found 97% among most active publishing scientists agreed that humans caused warming and endorsed by organisations from 80 countries
Hello, I don't think the 2013 consensus paper has been debunked by the article that you link. The non relevant papers were rejected from the 21 years of scientific papers and in those remaining there was a 97% consensus. Three other studies also found majority agreement. The question as to what degree has human activity changed the climate was not really relevant as it is virtually impossible to assess as so many factors such as solar, pollution, volcanoes and el nino and la nino affect warming. We only need to know if humans are affecting climate even if only in a small way (as we in a period of solar cooling and la Nina even a little warming means a lot of anthropogenic warming), on which there is consensus, yes humans affect the climate. Unless you survey non-climate scientists and manage to get 0.3% of them to sign a headline grabbing Petition Project rejecting the consensus.
Whether the stats on the 95% that more than half of climate change is human made are flawed or not doesn't change anything either as I have shown above. The proportion of climate change at this point is not relevant and is difficult to assess.
You haven't debunked anthropogenic climate change in any way shape or form. Just maybe educated some as to what stats and claims of percentages can and can't show.
https://georgiedonny.substack.com/p/climate-change-hasnt-been-debunked
Jo
A recovering liberal here. Thank you for opening my eyes to this, Prof. Fenton.
The hyperlink for "prosecutors fallacy" is broken or the website has been removed.
Professor Fenton, painstakingly helping the world to understand statistical legerdemain, one inquiring mind at a time.
Thanks for another helpful and informative exposition, Professor. The learning curves can be awfully steep, and a bit of guidance is greatly appreciated.
The data was and is tainted by bad science.
I remember seeing a photograph of a weather station in the middle of a field of grass and a subsequent photograph of it in a parking lot next to a building built long after the first photograph was taken. Same data acquisition point in a radically modified environment, producing just the long term temperature tread that the IPCC thrives on.
NASA: CO2 Greening Earth
https://m.youtube.com/watch?v=zOwHT8yS1XI&pp=ygUNbmFzYSBncmVlbmluZw%3D%3D
That’s melted my brain!!! Not being a mathematician or statistician I had to read that a couple of times! In my course language the IPCC and their scientists are bullshitting the world with their scaremongering!!!