Case Study 5 Instructions From page 548 of the etext: In your opinion, how safe is the food you buy? CBS News polled 1048 U.S. adults and asked them the question below. Overall, how confident are you that the food you buy is safe to eat: very confident, somewhat confident, not too confident, not at all confident? The pie chart shows the responses to the question. You conduct a survey using the same question. The contingency table shows the results of your survey classified by gender. How Confident Are You That Gender the Food You Buy is Safe to Eat? Response Female Male Not at all confident 2% Very Very confident 96 160 confident Somewhat confident 232 180 32% Not too confident 56 52 Not too confident Not at all confident 12 14% Somewhat confident 52%Calculate the Expected Value for all cells: Females Males Very Confident Somewhat Confident Not Too Confident Not At All ConfidentAt a = 0.01, perform a seven step chi-squared independence test to determine whether the variables response and gender are independent. What can you conclude? 1. Ho: The variables gender and responses are 2. Ha: The variables gender and responses are 3. Degrees of freedom = Significance Level = X' critical = (rounded to 3 decimal places) 4. Complete the table below with the Chi-Square contribution values for each cell Females Males Very Confident Somewhat Confident Not Too Confident Not At All Confident X2 test round to three decimal places) 5. p-value = round to four decimal places) 6. Result = ("Reject the null hypothesis" or "Fail to reject the null hypothesis") 7. Conclusion = There enough evidence, at the significance level of 0.01 to conclude that the variables gender and responses are (Enter: "is, is not, independent, dependent" as needed)Perform a seven step chi-squared goodness-of-fit test to compare the distribution of responses by females with the expected distribution. Use the distribution shown in the pie chart as the expected distribution. Use a = 0.05. What can you conclude? 1. Ho: The sample distribution a good fit for the expected values of the population. 2. Ha: The sample distribution a good fit for the expected values of the population. 3. X' critical = (rounded to 3 decimal places) 4. X2test = (rounded to 3 decimal places) 5. p-value = (rounded to 3 decimal places) 6. Result = "Reject the null hypothesis" or "Fail to reject the null hypothesis") 7. Conclusion = There enough evidence, at the significance level of 0.05 to conclude that the sample distribution a good fit for the expected values of the population. (Enter: "is, is not" as needed) Question 7 3 p Perform a seven step chi-squared goodness-of-fit test to compare the distribution of responses by males with the expected distribution. Use the distribution shown in the pie chart as the expected distribution. Use a = 0.05. What can you conclude? 1. Ho: The sample distribution a good fit for the expected values of the population. 2. Ha: The sample distribution a good fit for the expected values of the population. 3. X' critical (rounded to 3 decimal places) 4. X-test = (rounded to 3 decimal places) 5. p-value = rounded to 4 decimal places) 6. Result = ("Reject the null hypothesis" or "Fail to reject the null hypothesis") 7. Conclusion = There enough evidence, at the significance level of 0.05 to conclude that the sample distribution a good fit for the expected values of the population. (Enter: "is, is not" as needed)
