Module 6 Assignment 2 Correlation or Association and Prediction


Module 6 Assignment 2  Correlation or Association and Prediction.  Answer the following questions (160 points)

  1. Given the numbers of the X Variables on the X Axis (20, 25, 30, 35, 40, 50,) and the Y Variables on the Y Axis (10, 15, 20, 22, 34, 40) :
  1. Draw a Scatterplot graph to display the dotted correlation between the two variables (10pts)
  2. What direction does this correlation show (10pts)?
  3. Is this a positive, negative, no correlation, or moderate correlation (10 pts)
  4. Calculate the correlation coefficient value of Pearson r (Don’t forget to display in detail your calculation step by step as follows:
  5. Show table to display the data (10)
  6. Calculate the Mean for X (5pts)
  7. Calculate the Mean for Y (5pts.)
  8. Calculate the SX2 (10 pts)
  9. Calculate the SY2 (10pts)
  10. Calculate ∑XY (10pts)
  11. Calculate SXY (10 pts)
  12. What is Correlation coefficient r value (10 pts)
  13. What do you say about the strength and direction of the correlation between Y and X variables in this scenario (10)?
  1. If Mele earned a total Raw score of 500 out of 800 possible, on the ACT test given as one of the requirements for entrance into the Community College, and she was interested in Predicting her Algebra Grade at the end of her first Term in the Advanced Algebra Course.  With the following information known from the past years Algebra classes,

ACT  Mean, X=400.0

Algebra Mean  Y = 230.0

r = .14

SX  = 80

SY =  .20

  1. Following the equation procedure (^Y = bX + c) for solving the predicted ^Y, solve for prediction of her Algebra grade for the Term represented by ^Y (30 pts)
  2. Which of the following correlation coefficient indicates the strongest relationship? (a) .55  (b) .10  (c) .1 (d) negative .77 (10 pts)
  3. A relationship is Low to moderate, depicts which of these: (a) perfect (b) positive, (c) perfect negative, (d), none of these (10pts)