How many observations were used in the above regression? What percentage of the observed variability in Y is explained by X? What is the correlation between X and Y? Give the value of the t statistic for testing whether the slope between X and Y is zero. What's the predicted value of Y when X is 8? Find the error margin for a 98% confidence interval for the average value of Y when X is 8 Ex = 210 Ex = 2870 [xy = -10745 y = -759 y2 = 62523 Regression Equation: = 5.873684- 4.173684x Source Error SS Regression 11548.06053 Total df MS 33718.95 11548.06053 1 11584.06053 9.42011 1 22134.88947 18 1229.716 F LL 19