Home | Community | Message Board

Cannabis Seeds - Original Sensible Seeds
This site includes paid links. Please support our sponsors.


Welcome to the Shroomery Message Board! You are experiencing a small sample of what the site has to offer. Please login or register to post messages and view our exclusive members-only content. You'll gain access to additional forums, file attachments, board customizations, encrypted private messages, and much more!

Unfolding Nature Shop: Unfolding Nature: Being in the Implicate Order

Jump to first unread post Pages: 1
OfflineShroomerited
Male User Gallery

Registered: 06/12/10
Posts: 1,974
Last seen: 7 years, 10 months
Bayes' Theorem applied to drug testing
    #18745103 - 08/23/13 12:19 AM (10 years, 6 months ago)

http://en.wikipedia.org/wiki/Bayes'_theorem#Drug_testing

If you ever fail a test, just tell them you're more likely to NOT be a drug user than to be a drug user.


Extras: Filter Print Post Top
InvisibleModestMouse
IM WALKIN ON SUNSHINE
 User Gallery

Registered: 05/06/13
Posts: 19,227
Loc: Upstate
Re: Bayes' Theorem applied to drug testing [Re: Shroomerited]
    #18745150 - 08/23/13 12:30 AM (10 years, 6 months ago)

:imout:


--------------------
Anyone got a lowpass filter in this biiiiash?


Extras: Filter Print Post Top
OfflineLed Zeppelin
Tripper


Registered: 05/17/10
Posts: 3,962
Last seen: 3 years, 5 months
Re: Bayes' Theorem applied to drug testing [Re: ModestMouse]
    #18745295 - 08/23/13 01:14 AM (10 years, 6 months ago)

the only thing I understood was the part about speaking to the person on the train. common sense?


Extras: Filter Print Post Top
OfflineShroomerited
Male User Gallery

Registered: 06/12/10
Posts: 1,974
Last seen: 7 years, 10 months
Re: Bayes' Theorem applied to drug testing [Re: Led Zeppelin]
    #18745306 - 08/23/13 01:18 AM (10 years, 6 months ago)

Just read the part about the drug test. If a test is "99% accurate" and .5% of the population uses a drug and you test positive for it, you have a a 33% chance of actually being a drug user. So you're more likely to not be a drug user.


Extras: Filter Print Post Top
OfflineShroomerited
Male User Gallery

Registered: 06/12/10
Posts: 1,974
Last seen: 7 years, 10 months
Re: Bayes' Theorem applied to drug testing [Re: Shroomerited]
    #18745311 - 08/23/13 01:21 AM (10 years, 6 months ago)

This is only if .5% of the population uses the drug. If 10% uses the drug, there's a 93% chance you used it.


Extras: Filter Print Post Top
OfflineKonyap

Registered: 06/30/07
Posts: 33,945
Loc: Planet Piss
Last seen: 4 years, 3 months
Re: Bayes' Theorem applied to drug testing [Re: Shroomerited]
    #18745341 - 08/23/13 01:35 AM (10 years, 6 months ago)

I fucking hated probability I got an average of like 40 in it at some point.


Extras: Filter Print Post Top
Offlinedontknow
It's all in the reflex


Registered: 07/05/13
Posts: 3,889
Last seen: 7 years, 4 months
Re: Bayes' Theorem applied to drug testing [Re: Shroomerited]
    #18745342 - 08/23/13 01:36 AM (10 years, 6 months ago)

i can't rap my head around this one
:hanky:


--------------------
:box:

The discerning heart seeks knowledge, but the mouth of a fool feeds on folly. -Proverbs 15:14

:tripping2: :shroomer:  :trippinballs: :shroomin:

“Imagination is everything. It is the preview of Life’s coming attractions.”
Albert Einstein


Extras: Filter Print Post Top
OfflineKonyap

Registered: 06/30/07
Posts: 33,945
Loc: Planet Piss
Last seen: 4 years, 3 months
Re: Bayes' Theorem applied to drug testing [Re: Konyap]
    #18745345 - 08/23/13 01:38 AM (10 years, 6 months ago)

I understand the formula it's just this is a very odd scenario.


Extras: Filter Print Post Top
OfflineShroomerited
Male User Gallery

Registered: 06/12/10
Posts: 1,974
Last seen: 7 years, 10 months
Re: Bayes' Theorem applied to drug testing [Re: Konyap]
    #18745348 - 08/23/13 01:39 AM (10 years, 6 months ago)

Quote:

aiyobro said:
I understand the formula it's just this is a very odd scenario.



Mhmm. This.


Extras: Filter Print Post Top
OfflineKonyap

Registered: 06/30/07
Posts: 33,945
Loc: Planet Piss
Last seen: 4 years, 3 months
Re: Bayes' Theorem applied to drug testing [Re: Konyap]
    #18745350 - 08/23/13 01:39 AM (10 years, 6 months ago)

This surprising result arises because the number of non-users is very large compared to the number of users, such that the number of false positives (0.995%) outweighs the number of true positives (0.495%). To use concrete numbers, if 1000 individuals are tested, there are expected to be 995 non-users and 5 users. From the 995 non-users, 0.01 × 995 ≃ 10 false positives are expected. From the 5 users, 0.99 × 5 ≃ 5 true positives are expected. Out of 15 positive results, only 5, about 33%, are genuine.


Extras: Filter Print Post Top
OfflineKonyap

Registered: 06/30/07
Posts: 33,945
Loc: Planet Piss
Last seen: 4 years, 3 months
Re: Bayes' Theorem applied to drug testing [Re: Konyap] * 2
    #18745364 - 08/23/13 01:48 AM (10 years, 6 months ago)

Wow this makes that mandatory welfare drug testing look bad.


Extras: Filter Print Post Top
OfflineLed Zeppelin
Tripper


Registered: 05/17/10
Posts: 3,962
Last seen: 3 years, 5 months
Re: Bayes' Theorem applied to drug testing [Re: Konyap]
    #18745510 - 08/23/13 03:10 AM (10 years, 6 months ago)

I mean, is this really practical though? "yes, I know boss, I failed a test for cocaine, but you SEE, the probabilty of the percentage of the blah blah blah"


Extras: Filter Print Post Top
Offlinedruqs
ALKALOIDOHOLIC
 User Gallery

Registered: 09/11/06
Posts: 8,862
Last seen: 5 months, 12 hours
Re: Bayes' Theorem applied to drug testing [Re: Shroomerited]
    #18745519 - 08/23/13 03:17 AM (10 years, 6 months ago)

sounds like op is grasping at straws.


Extras: Filter Print Post Top
OfflineShroomerited
Male User Gallery

Registered: 06/12/10
Posts: 1,974
Last seen: 7 years, 10 months
Re: Bayes' Theorem applied to drug testing [Re: Led Zeppelin]
    #18746784 - 08/23/13 11:08 AM (10 years, 5 months ago)

Quote:

Led Zeppelin said:
I mean, is this really practical though? "yes, I know boss, I failed a test for cocaine, but you SEE, the probabilty of the percentage of the blah blah blah"



Of course not. If 10% of the population uses the drug and you fail a drug test, you have a 93% chance of being a drug user. Drug tests work because there's so many drug users.


Extras: Filter Print Post Top
InvisibleSophistic Radiance
Free sVs!
Female


Registered: 07/11/06
Posts: 43,135
Loc: Center of the Universe
Re: Bayes' Theorem applied to drug testing [Re: Shroomerited]
    #18746788 - 08/23/13 11:09 AM (10 years, 5 months ago)

Quote:

Shroomerited said:
Just read the part about the drug test. If a test is "99% accurate" and .5% of the population uses a drug and you test positive for it, you have a a 33% chance of actually being a drug user. So you're more likely to not be a drug user.




:mindblown:


--------------------
Enlil said:
You really are the worst kind of person.



Extras: Filter Print Post Top
Invisiblebadchad
Mad Scientist

Registered: 03/02/05
Posts: 13,373
Re: Bayes' Theorem applied to drug testing [Re: Sophistic Radiance]
    #18746955 - 08/23/13 11:50 AM (10 years, 5 months ago)

I don't think that will work.  In the case of drug testing, the worst scenario is a "false positive".  This is akin to accusing someone of using, when they don't.  The alternative, a "false negative", has lesser consequence. 

It's similar to the philosophy of you'd rather let a guilty man go free, than send an innocent man to jail.  We're much more concerned about the false positive in this case.

In this hypothetical scenario, the chances of a false positive are 1%.

It doesn't matter how many people use or don't use, the chance are 1%, period.


--------------------
...the whole experience is (and is as) a profound piece of knowledge.  It is an indellible experience; it is forever known.  I have known myself in a way I doubt I would have ever occurred except as it did.

Smith, P.  Bull. Menninger Clinic (1959) 23:20-27; p. 27.

...most subjects find the experience valuable, some find it frightening, and many say that is it uniquely lovely.

Osmond, H.  Annals, NY Acad Science (1957) 66:418-434; p.436


Extras: Filter Print Post Top
Invisiblevolcomstoner
I'll have just one more xanax
Male User Gallery


Registered: 07/20/09
Posts: 11,231
Loc: Minnesnowta
Re: Bayes' Theorem applied to drug testing [Re: badchad]
    #18746972 - 08/23/13 11:53 AM (10 years, 5 months ago)

I had a false negative once, I was pissed though because I needed to fail to get into treatment.


--------------------

HAIL SATAN

Vas donc jouer dans le traffic


Extras: Filter Print Post Top
Invisiblebadchad
Mad Scientist

Registered: 03/02/05
Posts: 13,373
Re: Bayes' Theorem applied to drug testing [Re: volcomstoner]
    #18746983 - 08/23/13 11:56 AM (10 years, 5 months ago)

Quote:

volcomstoner said:
I had a false negative once, I was pissed though because I needed to fail to get into treatment.




In clinical diagnostic tests, often times failure rates are designed around the worst possible scenario.  For example, one might argue that for HIV, a "false negative" is the worst outcome.


--------------------
...the whole experience is (and is as) a profound piece of knowledge.  It is an indellible experience; it is forever known.  I have known myself in a way I doubt I would have ever occurred except as it did.

Smith, P.  Bull. Menninger Clinic (1959) 23:20-27; p. 27.

...most subjects find the experience valuable, some find it frightening, and many say that is it uniquely lovely.

Osmond, H.  Annals, NY Acad Science (1957) 66:418-434; p.436


Extras: Filter Print Post Top
Jump to top Pages: 1

Unfolding Nature Shop: Unfolding Nature: Being in the Implicate Order


Similar ThreadsPosterViewsRepliesLast post
* Drug Test Your Teen Dot Com carbonhoots 5,468 12 01/02/04 02:16 AM
by Anno
* Failed my drug test!!!!!! djd586 4,369 9 05/16/04 09:47 AM
by ToTheSummit
* Drug Testing.... DxShroomFactor 3,011 11 11/01/03 03:55 PM
by synthesis
* Drug Tests Circlesongs 1,452 2 04/19/04 07:45 PM
by Mykey
* Stuck in a rut with drug testing :\ please help andySENSE311 2,482 13 06/05/04 09:59 PM
by ink
* tuesday night drug test
( 1 2 all )
daveball0420 3,109 21 05/13/04 10:37 AM
by Seuss
* Are you willing to submit to a drug test? *DELETED* oneducktwoducks 6,739 12 05/25/04 06:18 PM
by phi1618
* Dreams and drug tests. tak 2,106 9 10/31/03 06:58 PM
by tak

Extra information
You cannot start new topics / You cannot reply to topics
HTML is disabled / BBCode is enabled
Moderator: Entire Staff
757 topic views. 4 members, 46 guests and 46 web crawlers are browsing this forum.
[ Show Images Only | Sort by Score | Print Topic ]
Search this thread:

Copyright 1997-2024 Mind Media. Some rights reserved.

Generated in 0.023 seconds spending 0.005 seconds on 12 queries.