jam007

Q1 A public opinion poll surveyed a simple random sample of 1000 voters. Respondents were classified by gender (male or female) and by voting preference (Republican, Democrat, or Independent). Results are shown in the contingency table (Use attached data file Chi_Square.xls in the springboard, 10 points). 1) What are your Ho and Ha? (2 point) 2) What is a degree of freedom? (2 point) 3) At the 1% significance level, do the data provide sufficient evidence to conclude that an association exists between gender and voting preference? (3 point) 4) Does your analysis meet assumptions of Chi-square analysis? (3 points)

Q2. Three materials to make artificial teeth – Endura, Durandent, and Duracross – were tested for wear. Using a machine that simulated grinding by two right first molars at 60 strokes per minute for a total of 50,000 strokes, the researchers measured the volume of material worn away, in cubic millimeters. Six pairs of teeth were tested for each material. (Use attached data file ANOVA.xls in the springboard. 11 points) 1) What are your H0 and Ha? (2 point) 2) Check the assumptions of normality and homogeneity of variances (2 points) 3) At the 5% significance level, do the data provide sufficient evidence to conclude that there is a difference in mean wear among three materials? (3 point) 4) Do you need to conduct Post-Hoc test? Why or why not? (1 point) 5) Conduct a Post-Hoc test and determine which group is different from the others (3 points)