Null Hypotheses And Alternate Hypotheses Hypothesis Testing Hypotheses

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Null Hypotheses And Alternate Hypotheses

Null Hypotheses And Alternate Hypotheses

Hypothesis Testing Hypotheses are always about the population and never about the sample. The

Hypothesis Testing Hypotheses are always about the population and never about the sample. The true value of a hypothesis can never be known or confirmed. Conclusions regarding hypotheses are never absolute and as such are susceptible to some degree of definable/calculable risk of error. Type I Error Type II Error Rejecting H 0 when H 0 is True Failing to Reject H 0 when H 0 is False Probability of Type I Error = α Probability of Type II Error = β

Power of the Test Probability of Correctly Rejecting a False Null Hypothesis = 1

Power of the Test Probability of Correctly Rejecting a False Null Hypothesis = 1 - β Probability of Correctly Rejecting H 0 when H 1 is true = 1 - β Probability of Rejecting H 0 when H 0 is False = 1 - β Probability of Accepting H 1 when H 1 is True = 1 - β

Probability of Type I and Type II Errors The Level of Significance α establishes

Probability of Type I and Type II Errors The Level of Significance α establishes the Probability of a Type I Error. The Probability of a Type II Error depends on the magnitude of the true mean and the sample size.

Probability of Type II Errors Consider H 0: μ = μ 0 H 1:

Probability of Type II Errors Consider H 0: μ = μ 0 H 1: μ ≠ μ 0 Suppose the null hypothesis is false and the true magnitude of the mean is μ = μ 0 + δ. and therefore , that is to say Z 0 is normally distributed with mean and variance 1.

Probability of Type II Error Applied Statistics and Probability for Engineers, 3 ed, Montgomery

Probability of Type II Error Applied Statistics and Probability for Engineers, 3 ed, Montgomery & Runger, Wiley 2003