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Intro-Stat, Math 203 B, Quiz 2
  1. If you thought a person's IQ was affected by the average number of hours that person spent watching television each week, which variable (IQ or hours watching TV) would be the response variable?

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  2. Just by guessing, would you expect a scatterplot with X = hours of watching TV each week, and Y = IQ, to show a positive or negative association? Explain why you think this. Your score on this part will be based almost exclusively on your explanation, not whether you accurately predict the direction of the association.

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  3. Here are data on IQ and hours of watching TV each week for 10 students.
    4. Ten student's IQ and hours of TV viewing per week
    Y = IQ 110 105 120 140 100 125 130 105 115 110
    X = Hours TV 10 12 8 2 12 10 5 6 13 3

    Make a scatter plot of this data.
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     

  4. Based on your plot, would you say the association is strong, medium or weak?

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  5. What is the correlation r?

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  6. Which points (there may be several or none) seem NOT to fit the general pattern? Circle them and explain your choice.
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