Editing Talk:2476: Base Rate

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"''Aaaand we're back!''"<br>[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 17:01, 15 June 2021 (UTC)
: What happened? [[User:Bischoff|Bischoff]] ([[User talk:Bischoff|talk]]) 09:02, 16 June 2021 (UTC)
::I missed you! [[Special:Contributions/141.101.98.244|141.101.98.244]] 19:18, 15 June 2021 (UTC)
:::There is this : [https://www.explainxkcd.com/wiki/index.php/explain_xkcd:Community_portal/Miscellaneous#So_what_happened_to_the_site.3F post], but it does not help much yet... But great to be back live as long as it stays like this --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 12:08, 16 June 2021 (UTC)
:I never realised how much I relied on this site to keep me busy until it went down. <span style="text-shadow:0 0 7px black">[[User:Beanie|<span style="font-size:11pt;color:#dddddd">Beanie</span>]]</span> <sup><span style="text-shadow:0 0 4px #000000">[[User talk:Beanie|<span style="font-size:8pt;color:#dddddd">talk</span>]]</span></sup> 10:29, 17 June 2021 (UTC)
:: [[903: Extended Mind]] --[[Special:Contributions/172.69.33.111|172.69.33.111]] 05:19, 18 June 2021 (UTC)

I can't tell if cueball is holding the pointer in his left or right hand [[Special:Contributions/141.101.98.122|141.101.98.122]] 21:30, 15 June 2021 (UTC)
:If he's facing the audience, it's in his right hand. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 21:32, 15 June 2021 (UTC)

I wonder if we can expect a comic soon about fan sites going offline. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 21:32, 15 June 2021 (UTC)
:I really don't think Randall keeps an eye on this page... --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 11:36, 16 June 2021 (UTC)

I removed the claim that Cueball was left-handed; I don't think we can tell whether he is or isn't. --[[Special:Contributions/172.70.130.82|172.70.130.82]] 22:36, 15 June 2021 (UTC)
:There's now a claim that he's ''right''-handed, and I don't think that's reliable either. Yes, the "proper" way to do a presentation is to be facing away from the screen, but I've seen a lot of not-very-good presenters. [[User:BunsenH|BunsenH]] ([[User talk:BunsenH|talk]]) 04:30, 16 June 2021 (UTC)
::I’ll bet that about 90% of the not-very-good presenters you’ve seen were right-handed, therefore if Cueball is not very good, he’s probably right-handed.[[Special:Contributions/172.69.34.190|172.69.34.190]] 04:53, 16 June 2021 (UTC)
Wouldn't cueball be technically correct, despite his logical error? Given a set of people who make base-rate errors, with no other qualifications, and given that 90 percent are right handed, wouldn't that make 90 percent of the people who make base rate errors right handed? [[Special:Contributions/172.69.71.180|172.69.71.180]] 13:21, 16 June 2021 (UTC)
:That's the thing about base rate errors; they're not technically wrong, but they are useless from a practical standpoint in doing anything to help the problem, and are misleading about the nature of the issue leading people to make false conclusions, even if there is no detail that is not technically correct on its own.  Though 90% of the problem is with right handed people, that is only because 90% of all people are right handed, and trying to incorporate a focus on right handed people in any potential solution is no help at all.--[[Special:Contributions/172.70.126.2|172.70.126.2]] 23:12, 29 June 2021 (UTC)
:The triangle formed between his legs and the floor is isosceles. This would require either that he his stance is perpendicular to the viewer, or else he has non-standard hip geometry. With that premise, if we look at the lines of his arm on the 'right' (from the reader's perspective) the line between his arm and leg are parallel. In order for him to be facing the audience, but yet pointing backwards with his left hand, he would have to either rotate his torso, which would cause the arm/leg lines to be not parallel, or have a missing scapula in his right shoulder (normal human arms can't rotate backwards that far. Alternately, due to the visual placement of the whiteboard, cueball would have to be a very short individual for the base line to show between his biceps, or the board would have to be hung unusually high on the wall. None of that is conclusive, but the most reasonable explanation is that Cueball is left-handed, even if that's bad presentation form.[[Special:Contributions/172.69.68.79|172.69.68.79]] 15:21, 17 June 2021 (UTC)

:: Sure, but i think his non standard hip geometry is pretty evident given that his femurs attach directly to his spine. I think I've seen cueball shrug, from which i might infer that he had scapula, but from looking at him, I think it's easily likely that he has a tendon connecting his humeri to his skull. But i do think he's rotating his trunk anyway, because of his chin position. I find irony in the fact that a right - handed person would be making this erroneous analysis. Btw I appreciated this postural analysis so much that i made an account and am posting my ever comment[[User:Mx. Creant|Mx. Creant]] ([[User talk:Mx. Creant|talk]]) 05:15, 19 June 2021 (UTC)

:: Welcome to the community! Please be mindful of the fact that written communication lacks so much context. Your post could be reasonably read to be pretty mean and dismissive in tone. That's how I read it at first. I'm making the conscious choice to re-read it in the best possible light and say thanks for the kind comment re: my post inspiring you to join the community. :) [[User:DevAudio|DevAudio]] ([[User talk:DevAudio|talk]]) 14:32, 21 June 2021 (UTC)

Can someone explain here in the comments how, in the explanation, we go from that example of 1% / 5% false-positive rate to a 17% / 83%? [[Special:Contributions/172.69.34.190|172.69.34.190]] 17:14, 16 June 2021 (UTC)
:Take a population of 10,000 tests. From the premise: 1% (100) are true positives and 99% (9,900) are true negatives, regardless of testing. 5% of those TNs (9900*5% = 495) register positive, falsely. We aren't given a false-negative rate, so assuming all 100 TPs register as positive, correctly. 495+100=595 people showing as positive, but only the 100 TPs actually truly were, which is slightly ''less'' than 17% (100/595 = 16.8ish%) who have an accurate positive test, leaving a whopping value of slightly more than 83% of tested-positive individuals who were ''wrongly'' identified as positive. [[Special:Contributions/162.158.158.105|162.158.158.105]] 18:11, 16 June 2021 (UTC)
::Another explanation: the 5% is the answer to "What's the change of having a positive test knowning I'm healthy?" the 83% is the answer to "What's the change of being infected knowing I've got a positive test ?".
:::The latter answers "What's the chance of '''not''' being infected, knowing I have a positive test?", as I'm sure you really meant, but that's otherwise an excellent form of summary. [[Special:Contributions/141.101.99.177|141.101.99.177]] 13:33, 17 June 2021 (UTC)

Removed the example from the first paragraph.  Preserving it here for future reference/improvement.  The example is more complex and harder to understand than the example in the comic.

"For instance, imagine a disease that is present in 1% of the population, for which there is a test with a 5% false-positive rate. This test might be presented as "95% accurate", and so people who receive a positive result from such a test are likely to think they have the disease. However, someone who receives a positive test result has only a 17% chance of actually having the disease; a much more likely reason for the positive result, occurring in 83% of all positive test results, is a false (wrong) positive."
[[Special:Contributions/172.70.35.69|172.70.35.69]] 00:03, 18 June 2021 (UTC)