Chapter 10 Key Ideas and Words
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Section 10.1
o Null hypothesis
o Alternative hypothesis
o Two-tailed test, left-tailed test, right-tailed test
o Four possible outcomes from hypothesis testing (draw two-by-two table)
o Type 1 error
o Type 2 error
o Alpha = level of significance and it’s relationship to a type 1 error
o Stating the conclusion to a hypothesis tests
General steps
o Determine your question ; e.g., coin is fair vs. coin is not fair
o Rephrase your question in terms of a probability distribution and a parameter
o Combine the question and parameter into null and alternative hypotheses
o Determine your level of significance; e.g., alpha=0.05
o Collect the data
o Calculate the test statistic under the assumption that the null hypothesis is true
o Treating the test statistic as a random variable created with the null hypothesis being
true, determine the probability distribution of the test statistic
o Calculate if your observed test statistic is unusual
 Classical method
 determine critical value(s) using alpha
 Reject if test statistic is in reject region
 P-value method
 Assuming null is true, calculate probability of getting test statistic as
extreme or more extreme than what you got from your data
 Reject null hypothesis if p-value less than or equal to alpha
o State conclusion
Section 10.2
o Hypothesis testing for a population proportion
o Z-statistic
o Classical approach
o P-value approach
o Definition and interpretation of a p-value
o Specifics of working with a one-tailed vs. two-tailed test
Section 10.3
o Hypothesis tests for a population mean
o 1-sample t-statistic
o T distribution
 T-table
 Degrees-of-freedom
o Statistical vs. practical significance
o Section 10.6 : Power
 What is it?
 How do effect size and sample size affect power?