The process of distinguishing between the null hypothesis and the alternative hypothesis is aided by considering two conceptual types of errors. The first type of error occurs when the null hypothesis is wrongly rejected. The second type of error occurs when the null hypothesis is wrongly not rejected. (The two types are known as type 1 and type 2 errors.)
The process of distinguishing between the null hypothesis and the alternative hypothesis is aided by considering two types of errors. A Type I error occurs when a true null hypothesis is rejected. A Type II error occurs when a false null hypothesis is not rejected. 
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conceptual
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The first type of
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the
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wrongly rejected. The second type of
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the
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wrongly
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(The two types are known as type 1 and type 2 errors.)