If you were to construct a regression equation using the X variable to predict t
ID: 3238885 • Letter: I
Question
If you were to construct a regression equation using the X variable to predict the Y variable for each of the three sets of data, for which set of data would the equation have the most negative slope? If you were to compute a correlation between the X and Y variables for each of the three set of data, which set of data would yield a correlation closest to zero? If you construct a regression equation using the X variable to predict the Y variable for each of the data, for which set of data would the regression equation have largest positive slope?Explanation / Answer
18.
As we go from left to right in the scatterplot, if the points start going from up to down, then the slope of the scatterplot is negative. In the Scatterplot C it is clearly evident that the points have a negative slope.
19.
As we go from left to right if the it is very difficult to determine whether the points are going from up to down or from down to up, then the correlation coefficient would be close to zero. Of the three scatterplots given above, with Scatterplot B it we have evidence of random behaviour like this and hence it will be the one whose correlation coefficient is closest to zero.
20.
As we go from left to right if the points in general move from down to up position, then the scatterplot has positive slope. Among the given scatterplots this evidence can be observed only in Scatterplot A.