Difference between revisions of "Talk:2476: Base Rate"

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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)
 
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. 595+100=595 people showing as positive, but only the 100 were actually truly were, which is slightly ''less'' than 17% (100/595 = 16.8ish%) who have an accurate positive test, slightly more than 83% who were wrongly identified as positive. [[Special:Contributions/162.158.158.105|162.158.158.105]] 18:11, 16 June 2021 (UTC)
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: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. 595+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)

Revision as of 18:14, 16 June 2021

"Aaaand we're back!"
ProphetZarquon (talk) 17:01, 15 June 2021 (UTC)

What happened? Bischoff (talk) 09:02, 16 June 2021 (UTC)
I missed you! 141.101.98.244 19:18, 15 June 2021 (UTC)
There is this : post, but it does not help much yet... But great to be back live as long as it stays like this --Kynde (talk) 12:08, 16 June 2021 (UTC)

I can't tell if cueball is holding the pointer in his left or right hand 141.101.98.122 21:30, 15 June 2021 (UTC)

If he's facing the audience, it's in his right hand. Barmar (talk) 21:32, 15 June 2021 (UTC)
Typically cueball has a slightly noticeable 'chin' that indicates the direction he is looking (ex: #2471, #2468, #2460(cell 2 he looks at Megan and cell 3 looks away from her) ). So in this case I'd say he is looking to the right with his body facing the audience. --TallJason (talk) 15:52, 16 June 2021 (UTC)

I wonder if we can expect a comic soon about fan sites going offline. Barmar (talk) 21:32, 15 June 2021 (UTC)

I really don't think Randall keeps an eye on this page... --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. --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. 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.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? 172.69.71.180 13:21, 16 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%? 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. 595+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. 162.158.158.105 18:11, 16 June 2021 (UTC)