InvestorsHub Logo
Post# of 252431
Next 10
Followers 73
Posts 6214
Boards Moderated 0
Alias Born 05/01/2011

Re: iwfal post# 128688

Tuesday, 10/18/2011 3:15:42 PM

Tuesday, October 18, 2011 3:15:42 PM

Post# of 252431

Ok, and would your answer be different if I told you the false positive rate on the test was 30%?



So....

There's a 30% chance I've been misdiagnosed as having a disease that will kill me, for sure, in a week.

I can take drug A, which will cure me for sure, but then has a 20% chance of killing me with side effects, OR

I can take drug B, which will cure me 70% of the time, with no side effects.

Case 1: I have the deadly disease (70% chance)

Drug A: 20% chance of death x 70% = 14%
Drug B: 30% chance of death x 70% = 21%

Case 2: False positive, I'm fine (30% chance)

Drug A: 20% chance of death x 30% = 6%
Drug B: No chance of death

I have a 20% chance of dying with Drug A, and a 21% chance of dying with Drug B. Close to a wash, but I'm still in the Drug A camp.

“The trick is in what one emphasizes. We either make ourselves miserable, or we make ourselves happy. The amount of work is the same.” Carlos Castaneda

Join the InvestorsHub Community

Register for free to join our community of investors and share your ideas. You will also get access to streaming quotes, interactive charts, trades, portfolio, live options flow and more tools.