1. Essential Statistics Chapter 161 Review Part III_A_Chi Z-procedure Vs t-procedure

2. u Standard error (SE) u Confidence interval Essential Statistics Chapter 182 Standard Error & Confidence Interval In Proportions

3. Test Statistic for Proportions u Z test statistic u H 0 : p = p 0 u Single sided H a : p > p 0 H a : p < p 0 u Double sided H a : p ≠ p 0 Essential Statistics Chapter 183

4. Essential Statistics Chapter 214 u To determine if the differences between the observed counts and expected counts are statistically significant (to show a real relationship between the two categorical variables), we use the chi-square statistic: Chi-Square Statistic where the sum is over all cells in the table.

5. Essential Statistics Chapter 215 u The expected count in any cell of a two-way table (when H 0 is true) is Chi-Square Statistic: Expected Counts

6. Essential Statistics Chapter 216 u Chi-square test for a two-way table with r rows and c columns uses critical values from a chi-square distribution with (r  1)(c  1) degrees of freedom u P-value is the area to the right of X 2 under the density curve of the chi-square distribution –use chi-square table Degree of Freedom in Chi-Square Tests