Difference between revisions of "Bayesian probability"

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{{Bayesian}}
 
A '''bayesian''' is someone who views probability as a level of certainty relating to a potential outcome or idea. This is in contrast to a [http://lesswrong.wikia.com/index.php?title=frequentist&action=edit&redlink=1 frequentist] who views probability as a representation of how frequently a particular outcome will occur over any number of trials.
 
A '''bayesian''' is someone who views probability as a level of certainty relating to a potential outcome or idea. This is in contrast to a [http://lesswrong.wikia.com/index.php?title=frequentist&action=edit&redlink=1 frequentist] who views probability as a representation of how frequently a particular outcome will occur over any number of trials.
  
 
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An event with a probability of .6 (or 60%) will be viewed by a bayesian as stating "I am 60% confident event X will happen in this next trial", whereas a frequentist would view it as stating "Over 100 trials, we should observe event X approximately 60 times."
 
 
An event with a probability of .6 (or 60%) will be viewed by a bayesian as stating "I am 60% confident event X will happen in this next trial."
 
 
 
Whereas a frequentist would view it as stating "Over 100 trials, we should observe event X approximately 60 times."
 
 
 
 
 
  
 
The difference is more apparent when discussing ideas. A frequentist will not assign probability to an idea, either it is true or false and it cannot be true 6 times out of 10. A bayesian however views ideas in a different light, the probability of an idea being true is equal to the number of [[possible worlds|possible worlds]] where it is true out of the total number of [[possible worlds|possible worlds]].
 
The difference is more apparent when discussing ideas. A frequentist will not assign probability to an idea, either it is true or false and it cannot be true 6 times out of 10. A bayesian however views ideas in a different light, the probability of an idea being true is equal to the number of [[possible worlds|possible worlds]] where it is true out of the total number of [[possible worlds|possible worlds]].
  
  
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==See Also==
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== References ==
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==References==
 
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=== Overcoming Bias Articles ===
 
 
 
 
 
  
=== Less Wrong Articles ===
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=====Footnotes=====
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<references/>
  
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=====Overcoming Bias Articles=====
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=====Less Wrong Articles=====
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=== Other Resources ===
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*[http://yudkowsky.net/rational/bayes Bayes' Theorem]  by [http://lesswrong.wikia.com/wiki/Eliezer_Yudkowsky Eliezer Yudkowsky]
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*[http://yudkowsky.net/rational/bayes Bayes' Theorem]  by [[Eliezer Yudkowsky]]
 
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Revision as of 15:10, 19 April 2009

Template:Bayesian A bayesian is someone who views probability as a level of certainty relating to a potential outcome or idea. This is in contrast to a frequentist who views probability as a representation of how frequently a particular outcome will occur over any number of trials.

An event with a probability of .6 (or 60%) will be viewed by a bayesian as stating "I am 60% confident event X will happen in this next trial", whereas a frequentist would view it as stating "Over 100 trials, we should observe event X approximately 60 times."

The difference is more apparent when discussing ideas. A frequentist will not assign probability to an idea, either it is true or false and it cannot be true 6 times out of 10. A bayesian however views ideas in a different light, the probability of an idea being true is equal to the number of possible worlds where it is true out of the total number of possible worlds.


See Also

References

Footnotes


Overcoming Bias Articles
Less Wrong Articles
Other Resources