# Chi Square - Company W Is Testing Sales Software Essay

262 WordsJan 28, 20132 Pages
Chi –Square Distribution to test the independence of two variables Step 1: Set up the hypotheses: Hº: The variables are independent H¹: The variables are not independent. Step 2: Compute the expected frequency for each cell in the contingency table by use of the formula: E=Expected frequency= (Row total)(Column Total) _____________________ Sample size Step 3: Compute the statistic χ ²=Σ(O-E)² / E Where O is the observed frequency, E is the expected frequency, and the sum Σ is over all cells. Step 4: Find the critical value χ²α in Table A. 10 page 651. Use the level of significance of 0.01 and the number of degrees of freedom. d.f. to find the critical value. d.f.= (R-1)(C-1) Page 2 where R is the number of rows and C is the number of columns of cells in the contingency table. The critical region consists of all values of χ²α. Step5: Compare the sample statistic χ² of Step 3 with the critical value of χ²α of Step 4. If the sample statistic is larger, reject the null hypothesis of independence. Otherwise, do not reject the null hypothesis. Problem The following table shows the Myers-Briggs personality preference and professions for a random sample of 2408 people in the listed professions. Page 3 ____________________________________________________