Difference between revisions of "Talk:2599: Spacecraft Debris Odds Ratio"

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('280%' joke proof)
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::::Someone who do understand this method of getting to 280% should add that to the explanation. I'm not quite sure what is meant here above, so an even better explanation would be preferable. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 08:28, 29 March 2022 (UTC)
 
::::Someone who do understand this method of getting to 280% should add that to the explanation. I'm not quite sure what is meant here above, so an even better explanation would be preferable. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 08:28, 29 March 2022 (UTC)
 
:::<u>Joke proof</u>: ''Assume'' that every year 400 people are killed by bears in the world, of which 100 are killed inside and 300 are killed outside. Then, indeed, by going outside, the probability that you will be killed by bears increases from 100 to 300: that is 300%. On the other hand, we know that walking outside every day will reduce your risk of death from cardiovascular disease by 30%. Therefore, by walking outside properly, 30% of the above-mentioned 400 people, i.e. 120 people, could in theory avoid death from the said disease, ''if'' not attacked by bears. This implies that, even if everyone in the world walked outside every day, only 120 out of the 400 bear attack victims would be potentially saved, while 280 would die anyway. Since by hypothesis only 100 are killed inside by bear attacks, going outside will clearly increase the probability of deadly bear attacks, from 100 to 280: that is 280%. —[[User:Yosei|Yosei]] ([[User talk:Yosei|talk]]) 09:52, 29 March 2022 (UTC)
 
:::<u>Joke proof</u>: ''Assume'' that every year 400 people are killed by bears in the world, of which 100 are killed inside and 300 are killed outside. Then, indeed, by going outside, the probability that you will be killed by bears increases from 100 to 300: that is 300%. On the other hand, we know that walking outside every day will reduce your risk of death from cardiovascular disease by 30%. Therefore, by walking outside properly, 30% of the above-mentioned 400 people, i.e. 120 people, could in theory avoid death from the said disease, ''if'' not attacked by bears. This implies that, even if everyone in the world walked outside every day, only 120 out of the 400 bear attack victims would be potentially saved, while 280 would die anyway. Since by hypothesis only 100 are killed inside by bear attacks, going outside will clearly increase the probability of deadly bear attacks, from 100 to 280: that is 280%. —[[User:Yosei|Yosei]] ([[User talk:Yosei|talk]]) 09:52, 29 March 2022 (UTC)
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:::As said above, 300% increase and 30% decrease gives a factor ×2.8 <u>which is a +180% increase</u> (not 280%) [[Special:Contributions/162.158.50.176|162.158.50.176]] 10:38, 29 March 2022 (UTC)
  
 
"That's a 280% increased" has a typo/grammaro. The last word should be "increase". [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 23:04, 28 March 2022 (UTC)
 
"That's a 280% increased" has a typo/grammaro. The last word should be "increase". [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 23:04, 28 March 2022 (UTC)

Revision as of 10:38, 29 March 2022

correct me if i'm wrong, but i believe 300 - 30 is 270, not 280? 172.68.50.85 22:50, 28 March 2022 (UTC)

something something percentage points maybe? idk 172.70.134.91 22:56, 28 March 2022 (UTC)Bumpf
Most likely there is an unstated chance of death by not going outside... presumably ~10% but there's no way to know the breakdown (could be nearly all cardio, could be nearly all ursine if they live in a cave next bears) 172.69.70.127 23:02, 28 March 2022 (UTC)
300% increase is multiplying by (1+3), 30% decrease is multiplying by (1-0.3) , %increases are multiplicative so the increase is by a factor of 4*0.7=2.8, which is 280% of the original value (or a 180% increase). 162.158.146.69 (talk) (please sign your comments with ~~~~)
Yeah, barring a total mistake, that must be where the number came from, but it seems odd by the inconsistent way it is expressed, as it assumes the 300% increase for the bear attack is added to the initial value for a final amount of 400%, along with a similar treatment for the 30% decrease, but the 280% is simply the final value skipping past that step to the conclusion afterwards that is not even shown for the previous numbers. But with the improper grammar, if it's not an actual typo, it may be trying to show the speaker acting dumb or irrational, as it doesn't make sense to end with "increased" instead of "increase" without changing part of the words before that number. Someone thinking that poorly though likely wouldn't be able to multiply things properly to produce that 280% number though.--172.70.130.153 01:13, 29 March 2022 (UTC)
Someone who do understand this method of getting to 280% should add that to the explanation. I'm not quite sure what is meant here above, so an even better explanation would be preferable. --Kynde (talk) 08:28, 29 March 2022 (UTC)
Joke proof: Assume that every year 400 people are killed by bears in the world, of which 100 are killed inside and 300 are killed outside. Then, indeed, by going outside, the probability that you will be killed by bears increases from 100 to 300: that is 300%. On the other hand, we know that walking outside every day will reduce your risk of death from cardiovascular disease by 30%. Therefore, by walking outside properly, 30% of the above-mentioned 400 people, i.e. 120 people, could in theory avoid death from the said disease, if not attacked by bears. This implies that, even if everyone in the world walked outside every day, only 120 out of the 400 bear attack victims would be potentially saved, while 280 would die anyway. Since by hypothesis only 100 are killed inside by bear attacks, going outside will clearly increase the probability of deadly bear attacks, from 100 to 280: that is 280%. —Yosei (talk) 09:52, 29 March 2022 (UTC)
As said above, 300% increase and 30% decrease gives a factor ×2.8 which is a +180% increase (not 280%) 162.158.50.176 10:38, 29 March 2022 (UTC)

"That's a 280% increased" has a typo/grammaro. The last word should be "increase". Barmar (talk) 23:04, 28 March 2022 (UTC)

I think the actual typo is the "a" so should be "That's 280% increased" 162.158.146.69 (talk) (please sign your comments with ~~~~)

Also what's an odds ratio?? ~~Bumpf 172.70.38.41 (talk) (please sign your comments with ~~~~)

I assume something like "million to one". But the units of the horizontal axis clearly don't correspond to that. I don't know what those units are, they're not a percentage, either. Barmar (talk) 00:40, 29 March 2022 (UTC)
if you say "this is 4 times as likely" then "4" is the "odds ratio", this is the type of number appearing on the horizontal axis 162.158.146.69 (talk) (please sign your comments with ~~~~)
An odds-ratio is a way of reporting the results for predictions of binary outcomes. It's a transformation of the (not easily interpretable) regression coefficient. For example, if the OR for "males" (vs females) is "0.70", they're 70% as likely to have the outcome as females; if it's "1.32", then males are 1.32x as likely (equivalently: 32% more likely) to have that outcome as females. 108.162.249.75 Gye Greene

Did something happen to the size of the image after the initial posting? Barmar (talk) 00:40, 29 March 2022 (UTC)

What's with the asterisks on the right side? Jordan Brown (talk) 00:50, 29 March 2022 (UTC)

I think the asterisks denote that the value at this range is "significant" because its error bars do not overlap with the baseline. If you stay outdoors 5 hours or more in a day, there is a nonzero chance that you will be hit by flying space debris. Laura (talk) 08:15, 29 March 2022 (UTC)

There should probably be an explanation of what "Monte Carlo Simulation" means, as many people who would actually want an explanation of this strip would likely be unfamiliar with that term.--172.70.131.122 01:02, 29 March 2022 (UTC)

Yes, exactly! I got as far as finding Monte Carlo method via a redirect but have no idea how the bars are supposed to work, what the reference point is supposed to mean, or why the columns get skinnier toward the right. Not dumb, but next to no statistics education. Yngvadottir (talk) 07:51, 29 March 2022 (UTC)
Yes, I added some links to try to make the graph a little more explore-friendly for folks willing to click and read what's beyond, but I don't have the smarts to really explain it. Laura (talk) 08:00, 29 March 2022 (UTC)

Why is the x-axis of the chart in logarithmic spacing? Any particular reason for this, or is it part of the joke? Captain Nemo (talk) 09:29, 29 March 2022 (UTC)

Odds ratio confusion?

I am very confused by the X axis of this comic, I feel like I must be misunderstanding how this works, but I thought I understood how odds ratios worked. Maybe not. The graph "reads" that "In the reference situation, with zero hours spent outside, the odds ratio for head injuries from falling spacecraft debris is 1.0 ± 0." A 1.0 odds ratio means 1.0:1.0, or that either possibility is 50% likely. That is, there's an even chance your head will be injured by spacecraft debris or that it will not, if you stay indoors. That does not seem like it could be right, so can someone point me to my error? Thanks! JohnHawkinson (talk) 09:34, 29 March 2022 (UTC)