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How do you calculate the critical value?

User Lan
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Answer: The critical value is a value used in hypothesis testing to determine the rejection or acceptance of a null hypothesis. The critical value is determined based on the significance level of the test and the degrees of freedom. The critical value is usually determined from a table or calculated using statistical software.

Here are the general steps to calculate the critical value:

Determine the significance level, denoted by α. This is the probability of making a Type I error, which is the probability of rejecting a true null hypothesis.

Determine the degrees of freedom, which depend on the specific test and sample size.

Look up the critical value in a table of critical values for the appropriate significance level and degrees of freedom. These tables are available in most statistics textbooks or can be found online.

If a table is not available, the critical value can be calculated using statistical software or a calculator that provides a cumulative distribution function for the appropriate distribution. For example, the critical value for a two-tailed t-test can be calculated in R using the qt function. The syntax is qt(1-α/2, df), where α is the significance level and df is the degrees of freedom.

Note that the critical value will depend on the specific hypothesis test being performed and the null and alternative hypotheses. It is important to choose the correct test and use the appropriate critical value to ensure accurate results.

Explanation:

User Ryan Marcus
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