Editing 892: Null Hypothesis

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This comic (and the title text) is based on a misunderstanding. The {{w|null hypothesis}} is the hypothesis in a statistical analysis that indicates that the effect investigated by the analysis does ''not'' occur, i.e. 'null' as in zero effect. For example, the null hypothesis for a study about cell phones and cancer risk might be "Cell phones have no effect on cancer risk." The ''alternative hypothesis,'' by contrast, is the one under investigation - in this case, probably "Cell phones affect the risk of cancer."
 
This comic (and the title text) is based on a misunderstanding. The {{w|null hypothesis}} is the hypothesis in a statistical analysis that indicates that the effect investigated by the analysis does ''not'' occur, i.e. 'null' as in zero effect. For example, the null hypothesis for a study about cell phones and cancer risk might be "Cell phones have no effect on cancer risk." The ''alternative hypothesis,'' by contrast, is the one under investigation - in this case, probably "Cell phones affect the risk of cancer."
  
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After conducting a study, we can then make a judgment based on our data. There are statistical models for measuring the probability that a certain result occurred by random chance, even though in reality there is no correlation. If this probability is low enough (usually meaning it's below a certain threshold we set when we design the experiment, such as 5% or 1%), we ''reject'' the null hypothesis, in this case saying that cell phones ''do'' increase cancer risk. Otherwise, we ''fail to reject'' the null hypothesis, as we have insufficient evidence to conclusively state that cell phones increase cancer risk. This is how almost all scientific experiments, from high school biology classes to CERN, draw their conclusions.
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After conducting a study, we can then make a judgement based on our data. There are statistical models for measuring the probability that a certain result occurred by random chance, even though in reality there is no correlation. If this probability is low enough (usually meaning it's below a certain threshold we set when we design the experiment, such as 1%), we ''reject'' the null hypothesis, in this case saying that cell phones ''do'' increase cancer risk. Otherwise, we ''accept'' the null hypothesis, saying that cell phones ''do not'' increase cancer risk. This is how almost all scientific experiments, from high school biology classes to CERN, produce results.
  
 
It is very important to note that a null hypothesis is a specific statement relative to the current study. In mathematics, we often see terms such as "the Riemann hypothesis" or "the continuum hypothesis" that refer to universal statements, but a null hypothesis depends on context. There is no  one "''the'' null hypothesis." It refers to a method of statistical analysis (and {{w|falsifiability}}, not a ''specific'' hypothesis). Given that, [[Megan]]'s response would probably be to facepalm.
 
It is very important to note that a null hypothesis is a specific statement relative to the current study. In mathematics, we often see terms such as "the Riemann hypothesis" or "the continuum hypothesis" that refer to universal statements, but a null hypothesis depends on context. There is no  one "''the'' null hypothesis." It refers to a method of statistical analysis (and {{w|falsifiability}}, not a ''specific'' hypothesis). Given that, [[Megan]]'s response would probably be to facepalm.

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