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    Statistics Regression Question




    I need help with this question! The graph is in the picture below!

    A popular, nationwide standardized test taken by high-school juniors and seniors may or may not measure academic potential, but we can nonetheless examine the relationship between scores on this test and performance in college.
    We have chosen a random sample of fifteen students just finishing their first year of college, and for each student we've recorded her score on this standardized test (from 0 to 4) and her grade point average (from 400 to 1600) for her first year in college. The data are shown below, with X denoting the score on the standardized test and Y denoting the first-year college grade point average. A scatter plot of the data is shown in Figure 1.
    (This part is above the picture below)

    The least-squares regression line for these data has a slope of approximately 0.0017.Answer the following. Carry your intermediate computations to at least four decimal places, and round your answers as specified below.
    What is the value of the y-intercept of the least-squares regression line for these data? Round your answer to at least four decimal places.




    What is the value of the sample correlation coefficient for these data? Round your answer to at least three decimal places.
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    Re: Statistics Regression Question

    I am not sure what you are asking here. If you computations are correct?
    "Very few theories have been abandoned because they were found to be invalid on the basis of empirical evidence...." Spanos, 1995

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    Re: Statistics Regression Question

    I am not sure how to do this problem! If you could walk me it I would greatly appreciate it!

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    Re: Statistics Regression Question

    Start by consulting the list of formulas as suggested in the assignment and see if you can find a formula for the intercept.... When you have found a suggestion for the formula you can try and use it and/or ask more question if you need more help...

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    Re: Statistics Regression Question

    I narrowed it down to these two formulas, I am not sure which one it is. And then I'm having trouble identifying the order to which to plug the numbers into the formula?

    Least-squares regression line Formula

    Inference for correlation and regression Formula

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    Re: Statistics Regression Question


    Without knowing the formulas as the appear in your source ... I would guess that the question:

    What is the value of the y-intercept of the least-squares regression line for these data?

    could be answered using Least-squares regression line Formula ... you already have the slope 0.0017 so you need to find average og X and Y and plug into
    the formula

    a = average(Y) + b*average(X)

    where b is slope as explained on this page

    regression line formula

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