**This is timed. Don't take longer than 90 min to answer**

In order to predict y-values using the equation of a regression line, what must be true about the correlation coefficient of Question list K the variables? O Question 1 Choose the correct answer below. O A. The correlation between variables must be significant. O Question 2 O B. The correlation between variables must be a y-value of a point on the graph. O C. The correlation between variables must be an x-value of a point on the graph. O Question 3 O D. The correlation between variables must be greater than zero. O Question 4 O Question 5 O Question 6 O Question 7 Nextw Question list 0 Question 1 0 Question 2 0 Question 3 0 Question 4 0 Question 5 0 Question 6 0 Question 7 I Is it appropriate to use a regression line to predict yvalues for xvalues that are not in (or close to) the range of xvalues found in the data? E> Choose the correct answer below. [2:- A. It is appropriate because the regression line models a trend, not the actual points, so although the prediction of the yvalue may not be exact it will be precise. It is not appropriate because the regression line models the trend ofthe given data. and it is not known if the trend continues beyond the range of those data. It is appropriate because the regression line will always be continuous, so a yvalue exists for every xvalue on the axis. It is not appropriate because the correlation coefcient of the regression line may not be significant. Explain how to determine whether a sample correlation coefficient indicates that the population correlation coefficient is Question list K significant. O Question 1 Choose the correct answer below. O A. A scatterplot can be created to see if the sample values are accurate to within a critical value of the population O Question 2 values. O B. A table can be used to compare the absolute value of r with a critical value, or a hypothesis test can be performed using a t-test. Question 3 O C. The sample correlation coefficient r can be directly compared to the population coefficient. O D. A table can be used to compare the population coefficient with a critical value, or a hypothesis test can be performed using a t-test. O Question 4 O Question 5 O Question 6 Question 7 Next. _ What is a residual? Explain when a residual is positive, negative, and zero. Question list I E> O QueStlon 1 {:3 A. A residual is the difference between the observed yvalue of a data point and the predicted yvalue on a regression line for the xcoordinate of the data point. A residual is positive when the point is below the line, negative when it is above the line, and zero when the observed yvalue equals the predicted yvalue. O Quest'on 2 {j :3 B. A residual is the sum of the observed y-value of a data point and the predicted y-value on a regression line for the x-coordinate of the data point. A residual is positive when the point is above the line, negative when it is below the line, and zero when the observed yvalue equals the predicted yvalue. O Q t' 3 '1: j) C. A residual is the sum of the observed yvalue of a data point and the predicted yvalue on a regression line for \"es on the xcoordinate of the data point. A residual is positive when the point is below the line, negative when it is above the line, and zero when the observed yvalue equals the predicted yvalue. If} D. A residual is the difference between the observed yvalue of a data point and the predicted yvalue on a O Quest'on 4 regression line for the xcoordinate of the data point. A residual is positive when the point is above the line, negative when it is below the line, and zero when the observed y-value equals the predicted y-value. O Quest'on 5 O Quest'on 6 O Quest'on 7