Difference between revisions of "Talk:2323: Modeling Study"

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: One of my friends who studied thermal engineering remarked that if his model agreed with the test data to within ten degrees, it was acceptable, but if it agreed to less than five degrees, he was suspicious, because it was probably over-fit to the peculiarities of his thermal chamber, thermocouple placement, and so on, and less applicable for the system's real operational environment.  --[[User:NotaBene|NotaBene]] ([[User talk:NotaBene|talk]]) 23:40, 22 June 2020 (UTC)
 
: One of my friends who studied thermal engineering remarked that if his model agreed with the test data to within ten degrees, it was acceptable, but if it agreed to less than five degrees, he was suspicious, because it was probably over-fit to the peculiarities of his thermal chamber, thermocouple placement, and so on, and less applicable for the system's real operational environment.  --[[User:NotaBene|NotaBene]] ([[User talk:NotaBene|talk]]) 23:40, 22 June 2020 (UTC)
 
::We got trolled by our physics teacher in high school, during a calorimetry experiment (where you measure the changes in temperature of a system). All our measurements were way off from theoretical results, so we "adjusted" the reported values to make them fit the expected curve. Unfortunately, the prof knew that the thermometers were too inaccurate to produce precise results, so it was more of a test of our honesty, which we all failed miserably :-/[[Special:Contributions/162.158.158.167|162.158.158.167]] 13:19, 23 June 2020 (UTC)
 
::We got trolled by our physics teacher in high school, during a calorimetry experiment (where you measure the changes in temperature of a system). All our measurements were way off from theoretical results, so we "adjusted" the reported values to make them fit the expected curve. Unfortunately, the prof knew that the thermometers were too inaccurate to produce precise results, so it was more of a test of our honesty, which we all failed miserably :-/[[Special:Contributions/162.158.158.167|162.158.158.167]] 13:19, 23 June 2020 (UTC)
 +
:::In our Physics A-Level (normal post-Secondary and pre-University stage, for non-UKians) class, the 'trick' played on us was a 'black box' of components that we had to record the resistance/impedence/whatever of when raising the voltage (can't recall if DC or AC) from zero up to a level and then back down again. One of a number of such tests, to be done by rotating around the lab, you'd be tempted to just run it up and record the down as mirror image, or fudgingly near. Except that there was some sort of latching trip, once a given voltage went through the box, that changed the circuit significantly on the return trip. Only the honest (and possibly honest enough to show the 'error' that crept in, when thinking they'd messed it up - and no time to rerun it from scratch!) gave in the two-slope graph or whatever was the record. Can't tell you whether I was a Goody-Two-Shoes or not, though I like to think I was (and would have known about zenor diodes and self-reinfor ing flip-flop circuits, which this may have crudely used). [[Special:Contributions/141.101.98.130|141.101.98.130]] 23:44, 23 June 2020 (UTC)
 
:I once proof read a master thesis, where an experimental setting to optimize a problem in certain network arrangements was set up (basically a laboratory with 15 desktop PCs, communicating with each other on a specific protocol, etc.). The guy who wrote it found out on the first afternoon after setting it up, that the professor who found and described the problem he was about to tackle made a mistake, and the problem didn't exist. By that time he had already - due to university standards - handed in the name of his thesis. While negative results in research are also good results, the problem is, that by the same standards of his university his master thesis had to be a certain size - if I remember correctly, at least 50 pages in small font, excluding data and images - he managed to stretch his afternoons work and some subsequential tests on it to the required number of pages though. I am sure there is a lesson to be learned here, but... I haven't figured it out yet. --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 05:37, 23 June 2020 (UTC)
 
:I once proof read a master thesis, where an experimental setting to optimize a problem in certain network arrangements was set up (basically a laboratory with 15 desktop PCs, communicating with each other on a specific protocol, etc.). The guy who wrote it found out on the first afternoon after setting it up, that the professor who found and described the problem he was about to tackle made a mistake, and the problem didn't exist. By that time he had already - due to university standards - handed in the name of his thesis. While negative results in research are also good results, the problem is, that by the same standards of his university his master thesis had to be a certain size - if I remember correctly, at least 50 pages in small font, excluding data and images - he managed to stretch his afternoons work and some subsequential tests on it to the required number of pages though. I am sure there is a lesson to be learned here, but... I haven't figured it out yet. --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 05:37, 23 June 2020 (UTC)
 
::well, I gues the most important lesson would be "minimum length of text" is not a good requirement for any academic work. ;) [[User:Elektrizikekswerk|Elektrizikekswerk]] ([[User talk:Elektrizikekswerk|talk]]) 06:50, 23 June 2020 (UTC)
 
::well, I gues the most important lesson would be "minimum length of text" is not a good requirement for any academic work. ;) [[User:Elektrizikekswerk|Elektrizikekswerk]] ([[User talk:Elektrizikekswerk|talk]]) 06:50, 23 June 2020 (UTC)
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:Well, whoever makes statements like the one paraphrased above from the 2016 US election, or merely one like "there is a 75% chance of rain tomorrow", is a moronic pseudoscientist, and ought to be flogged, tarred, feathered, and sentenced to clean out public toilets 8h/d for two months, in that order. Such "measures" (of course they aren´t, they are merely a statement about how firmly one believes in his model extrapolating past measurement results into the future) have only one advantage for the "statistican" and newspapers, they can never be proved wrong. --[[Special:Contributions/162.158.92.44|162.158.92.44]] 20:38, 23 June 2020 (UTC)
 
:Well, whoever makes statements like the one paraphrased above from the 2016 US election, or merely one like "there is a 75% chance of rain tomorrow", is a moronic pseudoscientist, and ought to be flogged, tarred, feathered, and sentenced to clean out public toilets 8h/d for two months, in that order. Such "measures" (of course they aren´t, they are merely a statement about how firmly one believes in his model extrapolating past measurement results into the future) have only one advantage for the "statistican" and newspapers, they can never be proved wrong. --[[Special:Contributions/162.158.92.44|162.158.92.44]] 20:38, 23 June 2020 (UTC)
 +
:Ummm. If you run a thousand related but variously hedging weather simulations and 750 of them suggest rain (for a given set of criteria - temporal, geographical and terminological limits), then there's 75% chance of rain. This doesn't mean it'll rain only 75% of the typical raincloud or be raining steady for just 45 minutes in any hour. And the same with polling. No, you ''can't'' prove it "wrong" (unless you said 0% or 100% chance and it did or did not happen; anyone who said such things would be taking their own risk), and that's the point. If the models suggest a majority of at least one vote (EC, ideally, but based on the balloting levels) for one party in 85% of circumstances, it is valid to suggest an 85% chance. However tightly packed the scatter is across all half-reasonable patterns. (Which can be enumerated, for those that understand the enumerations, but how many who don't understand the original figure would understand any additional ones?) So you can't prove it wrong, just an unfortunate 'miss' (like a bet that two dice won't come up snake-eyes; even more certain, but it still does fail to go the promised way), and yet some would say it invalidates all modelling. That they don't like the look of. They'll happily use spurious/selective models that seem to share their viewpoint. (As will many different people with many different viewpoints, of course. Hopefully enough people consider enough competent models to appreciate enough of the true uncertainty. But I'm not sure the models support the more optimistic levels of 'enough'.) [[Special:Contributions/141.101.98.130|141.101.98.130]] 23:44, 23 June 2020 (UTC)
  
 
[https://dilbert.com/strip/2020-06-23 Dilbert makes the same point the next morning in a slightly different way]--[[User:Seebert|Seebert]] ([[User talk:Seebert|talk]]) 13:30, 23 June 2020 (UTC)
 
[https://dilbert.com/strip/2020-06-23 Dilbert makes the same point the next morning in a slightly different way]--[[User:Seebert|Seebert]] ([[User talk:Seebert|talk]]) 13:30, 23 June 2020 (UTC)

Revision as of 23:44, 23 June 2020

Also known as

I still have no clue about my subject, partly because I devised this study when I knew even less, but I need to write a paper anyway or I can never finish my PhD programme ...

vs.

I have now fiddled four years with my model assumptions to get the data to fit without, well, fiddling with the data, so please bear with me and my paper, and for heavens sake graduate me so I can save what is left of my soul and sanity ...  ;-) --162.158.94.94 20:23, 22 June 2020 (UTC)

One of my friends who studied thermal engineering remarked that if his model agreed with the test data to within ten degrees, it was acceptable, but if it agreed to less than five degrees, he was suspicious, because it was probably over-fit to the peculiarities of his thermal chamber, thermocouple placement, and so on, and less applicable for the system's real operational environment. --NotaBene (talk) 23:40, 22 June 2020 (UTC)
We got trolled by our physics teacher in high school, during a calorimetry experiment (where you measure the changes in temperature of a system). All our measurements were way off from theoretical results, so we "adjusted" the reported values to make them fit the expected curve. Unfortunately, the prof knew that the thermometers were too inaccurate to produce precise results, so it was more of a test of our honesty, which we all failed miserably :-/162.158.158.167 13:19, 23 June 2020 (UTC)
In our Physics A-Level (normal post-Secondary and pre-University stage, for non-UKians) class, the 'trick' played on us was a 'black box' of components that we had to record the resistance/impedence/whatever of when raising the voltage (can't recall if DC or AC) from zero up to a level and then back down again. One of a number of such tests, to be done by rotating around the lab, you'd be tempted to just run it up and record the down as mirror image, or fudgingly near. Except that there was some sort of latching trip, once a given voltage went through the box, that changed the circuit significantly on the return trip. Only the honest (and possibly honest enough to show the 'error' that crept in, when thinking they'd messed it up - and no time to rerun it from scratch!) gave in the two-slope graph or whatever was the record. Can't tell you whether I was a Goody-Two-Shoes or not, though I like to think I was (and would have known about zenor diodes and self-reinfor ing flip-flop circuits, which this may have crudely used). 141.101.98.130 23:44, 23 June 2020 (UTC)
I once proof read a master thesis, where an experimental setting to optimize a problem in certain network arrangements was set up (basically a laboratory with 15 desktop PCs, communicating with each other on a specific protocol, etc.). The guy who wrote it found out on the first afternoon after setting it up, that the professor who found and described the problem he was about to tackle made a mistake, and the problem didn't exist. By that time he had already - due to university standards - handed in the name of his thesis. While negative results in research are also good results, the problem is, that by the same standards of his university his master thesis had to be a certain size - if I remember correctly, at least 50 pages in small font, excluding data and images - he managed to stretch his afternoons work and some subsequential tests on it to the required number of pages though. I am sure there is a lesson to be learned here, but... I haven't figured it out yet. --Lupo (talk) 05:37, 23 June 2020 (UTC)
well, I gues the most important lesson would be "minimum length of text" is not a good requirement for any academic work. ;) Elektrizikekswerk (talk) 06:50, 23 June 2020 (UTC)
No. The most important lesson is "always name your thesis vaguely enough you can scale the content between 5% and 2000% or what you originally planned to do". -- Hkmaly (talk) 22:15, 23 June 2020 (UTC)

Various "<Problem> Denier" groups, (Climate Change, Covid, other things not necessarily starting with "C") do tend to lose their shit over "models" that aren't right (whether 1% out or 50%, they'll take any 'error', or just the failure to model what happened later because the model was heeded and behaviours changed to avoid the outcome) ironically using their clutched-at-straws to model all future models as wrong/intentionally-misleading-for-nefarious-intent. They also misunderstand the models (witness them dragging out old "85% chance Hillary will win" predictions against the roughly(-and-slightly-more-than) 50% of the votes she got - a different measure and far from incompatible with the other), whether innocently or deliberately, to 'prove' their point. And that's just done by regular Joes/Josephines. I'm sure you can be far more competently incompetent in your modelling (i.e. sneak sneaky shit past more and more learned people) if you're an actual modeller yourself who feels the need to drive towards an end for which you then look for the means. (Or modes, or medians.) 162.158.155.168 11:58, 23 June 2020 (UTC)

I'm nearly 18 hours late reading this comic, but the above is exactly why I'm so surprised to see it. Given Randall's apparent faith in mathematical modeling from other comics that this should be linked to (including the infamous vertical hockey stick temperature graph stretching back several millennia, and all the pro-Hillary bandwagon comics) I found this comic shocking in the extreme- he clearly knows the limitation of the method, and yet is still a true believer. Either that or he's finally growing up on the "A man who is not a liberal when he is young has no heart, a man who is not a conservative when he is old has no brains" spectrum. Seebert (talk) 13:27, 23 June 2020 (UTC)
Well, whoever makes statements like the one paraphrased above from the 2016 US election, or merely one like "there is a 75% chance of rain tomorrow", is a moronic pseudoscientist, and ought to be flogged, tarred, feathered, and sentenced to clean out public toilets 8h/d for two months, in that order. Such "measures" (of course they aren´t, they are merely a statement about how firmly one believes in his model extrapolating past measurement results into the future) have only one advantage for the "statistican" and newspapers, they can never be proved wrong. --162.158.92.44 20:38, 23 June 2020 (UTC)
Ummm. If you run a thousand related but variously hedging weather simulations and 750 of them suggest rain (for a given set of criteria - temporal, geographical and terminological limits), then there's 75% chance of rain. This doesn't mean it'll rain only 75% of the typical raincloud or be raining steady for just 45 minutes in any hour. And the same with polling. No, you can't prove it "wrong" (unless you said 0% or 100% chance and it did or did not happen; anyone who said such things would be taking their own risk), and that's the point. If the models suggest a majority of at least one vote (EC, ideally, but based on the balloting levels) for one party in 85% of circumstances, it is valid to suggest an 85% chance. However tightly packed the scatter is across all half-reasonable patterns. (Which can be enumerated, for those that understand the enumerations, but how many who don't understand the original figure would understand any additional ones?) So you can't prove it wrong, just an unfortunate 'miss' (like a bet that two dice won't come up snake-eyes; even more certain, but it still does fail to go the promised way), and yet some would say it invalidates all modelling. That they don't like the look of. They'll happily use spurious/selective models that seem to share their viewpoint. (As will many different people with many different viewpoints, of course. Hopefully enough people consider enough competent models to appreciate enough of the true uncertainty. But I'm not sure the models support the more optimistic levels of 'enough'.) 141.101.98.130 23:44, 23 June 2020 (UTC)

Dilbert makes the same point the next morning in a slightly different way--Seebert (talk) 13:30, 23 June 2020 (UTC)