Statistics Fundamentals Unit 5 Challenge 5,100% CORRECT

What is NOT assumed before starting an ANOVA test? • a.) The population standard deviations are similar. • b.) Populations are normally distributed. • c.) The population means are the same. • d.) The observations are independent and from a random sample. • c.)Correct. A one way ANOVA is used to test the differences in population mean values. So we don't assume they are the same. We are testing to see if there is evidence if they are the same or different. Which of the following is an example of a two-way ANOVA test? • a.) Comparing the number of hours that freshman and seniors study during a semester. • b.) Analyzing the number of hours that freshman, sophomores, juniors, and seniors study in a semester as well as the number of hours of sleep each group gets at night. • c.) Comparing the number of hours of sleep for freshman, sophomores, juniors, and seniors. • d.) Studying the number of hours of sleep for freshmen, sophomores, and juniors. Karen recorded the results for a sample of 518 candies. Color Counts Sample Proportion ( ) Red 130 25% Yellow 109 21% Green 93 18% Orange 114 22% Purple 72 14% The candy company claims that the distribution of each color is exactly 20%. Select the observed and expected frequencies for the green candies. • a.) Observed: 103.6 Expected: 93 • b.) Observed: 93 Expected: 93.2 • c.) Observed: 93 Expected: 103.6 • d.) Observed: 72 Expected: 93.2 Cindy recorded the number of customers who visited her new shop during the week: Day Customers Wednesday 18 Thursday 20 Friday 25 Saturday 17 She expected to have 20 customers each day. To determine whether the number of customers follows a uniform distribution, a chi-square test for goodness of fit should be performed (alpha = 0.10). Using the data above, what is the chi-square test statistic? Answer choices are rounded to the hundredths place. • a.) 0.37 • b.) 1.9 • c.) 3.51 • d.) 0.55 A table represents the possibility of an association between eye color and hair color. Hair Color Eye Color Brown Black Green 22 15 Blue 18 19 In order to determine if there is a significant difference between eye color and hair color, the chi-square test for association and independence should be performed. What is the expected frequency of Blue Eyes and Black Hair? • a.) 18 • b.) 20 • c.) 19 • d.) 17 • d.)Correct. In order to get the expected count we use the formula: The row total of blue eyes is 18 + 19 = 37. The column total of black hair is 15 + 19 = 34. The total of the whole table is 22 + 15 + 18 +19 = 74. So the expected frequency of blue eyes and brown hair is: A table represents the possibility of an association between eye color and hair color. Hair Color Brown Black Eye Color Green 22 15 Blue 18 19 What is the degrees of freedom? • a.) 4 • b.) 2 • c.) 1 • d.) 3 • c.)Correct. In order to get degrees of freedom, we use the following formula: