AP Statistics 2017

(Marvins-Underground-K-12) #1

CHAPTER 7


Two-Variable Data Analysis




  1.      In  the scatterplot,    the dashed  lines   represent   the mean    values  of  the two variables.  Removing    point   A

    would have which of the following effects?
    (A) The slope of the regression line would increase, and the correlation would decrease.
    (B) The slope of the regression line would decrease, and the correlation would increase.
    (C) The slope of the regression line would not change, and the correlation would increase.
    (D) The slope of the regression line would not change, and the correlation would decrease.
    (E) Neither the slope of the regression line nor the correlation would change.



  2. A statistics professor has collected data over the years on the midterm exam and final exam scores
    for his students. There is a positive linear association between the two sets of scores, and the
    correlation is 0.73. The standard deviation of midterm scores is 15 points, and the standard deviation
    of final exam scores is 25 points. If a student scores 18 points above the mean score on her midterm
    exam, about how far above the mean final exam score is her predicted final exam score?
    (A) 18 points
    (B) 22 points
    (C) 30 points
    (D) She would be predicted to get 0 points on the final exam.
    (E) It is impossible to calculate this without knowing the mean scores.

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