Unformatted text preview: the null or the alternative is true, but not both-Ideally, the hypothesis testing procedure should lead to the acceptance of H when H is true and the rejection of H when H a is true-Accepting H when H a is true is a Type II error, and rejecting H when H is true is a Type I error-The probability of making a Type I error when the null hypothesis is true as an equality is called the level of significance-The level of significance is denoted by , and is commonly .05 or .01-By selecting the level of significance, one is controlling the probability of making a Type I error ; if the cost of making a Type I error is high, small values of are preferred. In contrast, if the cost of making a Type I error is not high, larger values of can be used-Applications of hypothesis testing that only control for the Type I error are often called significance tests Population Mean: Known One-Tailed Test-...
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- Fall '07
- Null hypothesis, Statistical hypothesis testing, Type I and type II errors