STATISTICS
posted by SROBSON .
A) If a regression experiment has correlation coefficient r= 0.75, what precent of total variation is explained by the regression?
B) if 85% of total variation is explained by the regression, and there is an inverse relationship between y and x, then what is the correlation coefficient?
C) if 30% of the total variation is not explained by the regression, then what is the correlation coefficient? Assume a direct relationship between y and x.

STATISTICS 
MathGuru
The coefficient of determination deals with variation and is a measure of how well any given regression line represents its data. If a regression line passes through every point, all of the variation could be explained. The further the regression line is away from the points, the less can be explained.
You square the correlation coefficient to get the coefficient of determination.
Let's look at Part A as an example. If r = 0.75, then r^2 = 0.5625, which means that approximately 56% of the total variation in y can be explained by the linear relationship between x and y. The other 44% of the total variation in y is unexplained.
I hope this will help get you started.
Respond to this Question
Similar Questions

Business Statistics
If the total variation in y values is 200, and the variation explained by regression line is 180, then the coefficient of determination is equal to __________. A) 1.11 B) 0.90 C) 0.81 D) 1.21 I picked D 1.21 
Statistics
Hi Can anyone tell me in a regression model are the values of 0.13 0.10 A good indication of of the total y explained in a regression model ? 
research evaul 342
If the coefficient of correlation is –0.81, then the percentage of the variation in y that is explained by the regression line is 81%. A. True B. False 
statistics
Pre study scores versus post study scores for a class of 120 college freshman english students were considerated. The residual plot for the least squares regression line showed no pattern. The least squares regression line was y^=0.2+0.9x … 
statistics
Pre study scores versus poststudy scores for a class of 120 college freshman english students were considerated. The residual plot for the least squares regression line showed no pattern. The least square regression line was y = 0.2 … 
statistics
If the correlation coefficient is 0.54, what is the sign of the slope of the regression line? 
Statistics
Using advertised prices for used Ford Escorts a linear model for the relationship between a car's age and its price is found. The correlation coefficient is  0.933 Determine R2 and interpret this statistic. A) R2 = 93.3% which means … 
Statistics
Using advertised prices for used Ford Escorts a linear model for the relationship between a car's age and its price is found. The correlation coefficient is  0.933 Determine R2 and interpret this statistic. A) R2 = 93.3% which means … 
Math
A perfect positive or negative correlation means that A) the explanatory causes the yvariable. B) 100% of the variation is explained. C) we get the same regression equation if we switch the x and y variables. D) the slope of the regression … 
stats
Find the explained variation for the paired data. The equation of the regression line for the paired data below is yhat = 3x. Find the explained variation. x= 2 4 5 6 y= 7 11 13 20