Dr. Sarah's SAT Scores Lab adapted from a lab by Dr. Greg Rhoads

Dear Math 1010 students,
My name is Newbie Nevertookstats, and I just started a job as a reporter at USA Today. I was just been handed a data set containing SAT and GPA info for 200 juniors at a certain university and my boss wants me to write an article on this for the next issue. Unfortunately, I've never taken a stats course, so I need your help! My report is due in 1 week, so please help me by then!
Newbie Nevertookstats

From Dr. Sarah- Each group should include the following in one report aimed at the reporter. Be sure to use the checklist as a guideline.

  • Open Word, and start a letter to the reporter. Include the fact that the directions for creating the Minitab graphs can be found on this sheet which you will enclose with the lab. SAVE OFTEN.
  • Under Apple, Math 1010 Apps, open Minitab 10.5
    Under File, release Open Worksheet. If necessary, use the double arrow to go to Places and then to Applications HD /Applications/Minitab 105/Data and scroll down and open grades.mtw.

    Three Histograms Under Graph, release Histogram.... The X value under Graph 1 should be highlighted.

  • VERBAL HISTOGRAM
    Double click on VERBAL. Create a VERBAL histogram by using OK.
    Make the histogram smaller by clicking on the bottom right corner, and draging this up and to the left.
    Copy the VERBAL histogram by using Copy Graph under Edit.
    Paste the VERBAL histogram into Word by using Paste under Edit in Word
    Be careful about your placement of the graphs in Word. Do not attempt to move graphs around in word - start a new line before you paste a graph, and then start typing right after this
    Explain to Newbie that this is a histogram of Verbal SAT scores, and explain in depth what kind of info he can read off - give some specific examples.
  • Repeat the VERBAL HISTOGRAM instructions to create, paste and discuss histograms for MATH and GPA.

    Two Boxplots Under Window, Close All Graphs. Under Graph, release Boxplot.... The Y value under Graph 1 should be highlighted.

  • GPA Boxplot
    Double click on GPA. Create a GPA boxplot by using OK.
    Make the boxplot smaller by clicking on the bottom right corner, and draging this up and to the left.
    Copy the GPA boxplot by using Copy Graph under Edit.
    Paste the GPA boxplot into Word by using Paste under Edit in Word
    Explain to Newbie that this is a boxplot of GPA grades, and explain in depth what kind of info he can read off - give some specific examples. Some answers to include:
  • Between what grades were...
    the highest 25%?
    the middle 50%? (ie those students not in the highest or lowest 25%)
    the lowest 25%?
  • What do the stars mean?
  • What does it mean (in words about GPA) that the median is closer to the 1st quartile than it is to the 3rd quartile?

  • VERBAL and MATH Boxplot Under Graph, release Boxplot.... Double click on VERBAL.
    Move to the Y value for Graph 2 and double click on MATH.
    Under Frame, release Multiple Graphs... Choose Overlay graphs on the same page and then OK
    Under Edit Attributes..., for Graph 1, choose Fill Type Right Slant. For Graph 2, choose Fill Type Dots. Choose OK.
    Create one boxplot for both VERBAL and MATH by using OK.
    Make the boxplot smaller by clicking on the bottom right corner, and draging this up and to the left.
    Copy the VERBAL and MATH boxplot by using Copy Graph under Edit.
    Paste the VERBAL and MATH boxplot into Word by using Paste under Edit in Word
    Explain to Newbie that this is a boxplot of VERBAL and MATH SAT scores, and explain in depth what kind of info he can read off - give some specific examples. In addition, answer the same questions that you answered for GPA (For the last question, notice that for MATH the median looks to be just about in the middle.)

    Three Linear Regression Plots Under Window, Close All Graphs...
    You can create a linear regression by going to Regression under the Stat menu, then releasing on Fitted Line Plot. The Y variable is the Quality and the X variable is the best predictor; then click OK.

  • Create and paste regression plots in order to answer the following questions for Newbie. Before copying, make the plot large enough to read and copy down the r^2 value, and then make it smaller again to paste it into word. Answer the questions both mathematically via the r^2 value and the graph itself, and also using common sense:
  • Is VERBAL SAT score a good predictor of college GPA?
  • Is MATH SAT score a good predictor of college GPA?
  • Is VERBAL SAT score a good predictor of MATH SAT score?