Hypothesis testing Hypothesis testing From confidence intervals to t‐tests to t tests
Statistical hypotheses Statistical hypotheses • We always set up two hypotheses… • The null hypothesis = default pattern or relationship – Holds when “nothing special has occurred” H ld h “ thi i lh d” – Accept if no change has taken place
• The alternative hypothesis = can be 1 of 2 things... – Accept if change has taken place – Accept if change has taken place in a particular direction Accept if change has taken place in a particular direction
• You MUST reject the null to accept the alternative