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Using your favorite statistics software package, you generate a scatter plot which displays a linear form. you find a regression equation and the standard deviation for both variables. the standard deviation for x is 1.56, and the standard deviation for y is 5.46. the regression equation is reported as y=-5.7 + 1.74x what fraction of the variation in y can be explained by the variation in the values of x? (enter your answer as a decimal between 0 and 1.)

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Final answer:

To determine the fraction of the variation in y explained by x, we need to calculate the coefficient of determination (r²). This can be done using the correlation coefficient and the regression equation. The coefficient of determination represents the proportion of the total variation in y that can be explained by the regression line.

Step-by-step explanation:

To determine what fraction of the variation in y can be explained by the variation in x, we need to calculate the coefficient of determination (r²).

The coefficient of determination (r²) represents the proportion of the total variation in y that can be explained by the regression line. It ranges from 0 to 1, where 0 indicates no relationship and 1 indicates a perfect fit.

In this case, the regression equation is y = -5.7 + 1.74x. Since the coefficient of determination is equal to the square of the correlation coefficient (r), we can square the correlation coefficient to find r².

Given that the standard deviation for x is 1.56 and the standard deviation for y is 5.46, we can use these values to calculate the correlation coefficient, which is then squared to find r².

Using a statistics software package, the correlation coefficient can be calculated by dividing the covariance of x and y by the product of their standard deviations.

Once r² is determined, it represents the fraction of variation in y that can be explained by the variation in x. For example, if r² is 0.5, then 50% of the variation in y can be explained by the variation in x.

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