Difference between revisions of "795: Conditional Risk"

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(Created page with "{{comic | number = 795 | date = September 20, 2010 | title = Conditional Risk | image = conditional_risk.png | titletext = 'Dude, wait -- I'm not Amer...")
 
(Created trivia section for trivia, citation is actually needed, but the purpose of that tag is a joke so tag was removed.)
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{{comic
 
{{comic
 
| number    = 795
 
| number    = 795
| date      = September 20, 2010
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| date      = September 20, 2010
 
| title    = Conditional Risk
 
| title    = Conditional Risk
 
| image    = conditional_risk.png
 
| image    = conditional_risk.png
| titletext = 'Dude, wait -- I'm not American! So my risk is basically zero!'
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| titletext = 'Dude, wait -- I'm not American! So my risk is basically zero!'
 
}}
 
}}
  
 
==Explanation==
 
==Explanation==
The comic deals with the difference between general probability of certain event based on entire past history and the probability of the same event in particular circumstances. While the chance of any American selected randomly from general population to be killed by lightning is very low, for a particular person already being in the circumstances where lightning might strike him or her (such as being in the midst of a thunderstorm) is much higher. Since the statistics provided talks only about Americans, the other character wrongly assumes the chance to be struck by lightning for non-American is non-existant - which underlines the difference between knowing certain event can't or didn't happen and not having any data about the event.  
+
The comic deals with the difference between the general probability of a certain event based on history and the probability of the same event in particular circumstances. The chance of any American selected randomly from the general population to be killed by lightning is very low, but part of the reason for this is that an average American would seek shelter and safety when caught in a lightning storm. The joke is that someone armed with this particular statistical knowledge would not take the normal precautions and therefore leave themselves far more vulnerable.
  
The "one in six" statistic is probably invented by the author - which is also illuminates the danger of dealing with "statistical data" provided by random sources without any attribution to actual statistical surveys or hard data.  
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In the title text, since the statistic provided talks only about Americans, the other character wrongly assumes that lightning strikes ''only'' happen to Americans, rather than the data for lightning strikes for other nationalities being simply not included in the discussion. Because of this, as a non-American, he believes his chance of being struck by lightning is nonexistent - which underlines the difference between knowing a certain event can't or didn't happen and not having any data about the event. (With computers, 'null' and 'undefined' mean there is no data, while '0' means 0. Sometimes bad computer systems will assume null means zero)
 +
 
 +
The "one in six" statistic is probably invented by the author - which also illuminates the danger of dealing with "statistical data" provided by random sources without any attribution to actual statistical surveys or hard data. And of course, now all xkcd readers know the statistic, likely bringing down the death rate.
  
 
==Transcript==
 
==Transcript==
<!-- The transcript can be found in a hidden <div> element on the xkcd comic's html source, with id "transcript".
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:[Lightning strikes the ground, illuminating trees with a bright white light. Two people are standing near it. One has a walking stick.]
  -- Tip: Use colons (:) in the beginning of lines to preserve the original line breaks.
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:''CRACK''
  -- Any actions or descriptive lines in [[double brackets]] should be reduced to [single brackets] to avoid wikilinking
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:''BOOM''
  -- Do not include the title text again here -->
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:First person: Whoa! We should get inside!
: [ [Lightning strikes the ground, illuminating trees with a bright white light. Two people are standing near it. One has a walking stick.]]
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:Second person: It's okay! Lightning only kills about 45 Americans a year, so the chances of dying are only one in 7,000,000. Let's go on!
: &lt;&lt;CRACK&gt;&gt;
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: &lt;&lt;BOOM&gt;&gt;
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:[Caption below the panel:]
: First person: Whoa! We should get inside!
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:The annual death rate among people who know that statistic is one in six.
: Second person: It&#39;s okay! Lightning only kills about 45 Americans a year, so the chances of dying are only one in 7,000,000. Let&#39;s go on!
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:
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==Trivia==
: The annual death rate among people who know that statistic is one in six.
+
 
 +
Many people in the US were kept from voting because they had no location coordinates. The system assumed that 'no coordinates' meant 0 degrees north, 0 degrees east, which is NOT in the US and so they could not vote.
  
{{comic discussion}}  
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{{comic discussion}}
<!-- Include any categories below this line-->
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[[Category:Comics featuring Cueball]]
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[[Category:Comics with inverted brightness]]
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[[Category:Statistics]]

Revision as of 15:55, 26 May 2017

Conditional Risk
'Dude, wait -- I'm not American! So my risk is basically zero!'
Title text: 'Dude, wait -- I'm not American! So my risk is basically zero!'

Explanation

The comic deals with the difference between the general probability of a certain event based on history and the probability of the same event in particular circumstances. The chance of any American selected randomly from the general population to be killed by lightning is very low, but part of the reason for this is that an average American would seek shelter and safety when caught in a lightning storm. The joke is that someone armed with this particular statistical knowledge would not take the normal precautions and therefore leave themselves far more vulnerable.

In the title text, since the statistic provided talks only about Americans, the other character wrongly assumes that lightning strikes only happen to Americans, rather than the data for lightning strikes for other nationalities being simply not included in the discussion. Because of this, as a non-American, he believes his chance of being struck by lightning is nonexistent - which underlines the difference between knowing a certain event can't or didn't happen and not having any data about the event. (With computers, 'null' and 'undefined' mean there is no data, while '0' means 0. Sometimes bad computer systems will assume null means zero)

The "one in six" statistic is probably invented by the author - which also illuminates the danger of dealing with "statistical data" provided by random sources without any attribution to actual statistical surveys or hard data. And of course, now all xkcd readers know the statistic, likely bringing down the death rate.

Transcript

[Lightning strikes the ground, illuminating trees with a bright white light. Two people are standing near it. One has a walking stick.]
CRACK
BOOM
First person: Whoa! We should get inside!
Second person: It's okay! Lightning only kills about 45 Americans a year, so the chances of dying are only one in 7,000,000. Let's go on!
[Caption below the panel:]
The annual death rate among people who know that statistic is one in six.

Trivia

Many people in the US were kept from voting because they had no location coordinates. The system assumed that 'no coordinates' meant 0 degrees north, 0 degrees east, which is NOT in the US and so they could not vote.


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Discussion

"I'm not American! So my risk is basically zero!"

Is the risk to Americans so low because lightning concentrates on non-Americans?

I used Google News BEFORE it was clickbait (talk) 15:42, 26 January 2015 (UTC)


The line 'The annual death rate among people who know that statistic is one in six' clearly points out that the people who know the statistic tend to be dismissive about the danger of the lightning strikes and put themselves in danger. Even though the statistic is probably invented by the author, shouldn't it go in the explanation?

I did not want to change the explanation without a discussion. (PS: I am a newbie here)

A2658742 (talk) 10:44, 10 April 2015 (UTC)a2658742

I'd like to point out that the "invented one in six statistic" is a roll of the dice. 162.158.90.161 (talk) (please sign your comments with ~~~~)

1 in 6 is also the probability of shooting yourself in (classic) russian roulette. Siv3nIvy (talk) 11:41, 8 September 2016 (UTC)

This comic has been cited to illustrate the confusion of base vs conditional probability in Steven Pinker's new book [“Rationality: What It Is, Why It Seems Scarce, Why It Matters.”] --Agovita (talk) 11:17, 19 October 2021 (UTC)