Matchmaking with Statistics
Your job is to use the class data on faculty & spouses heights to help Mr. Bower decide on the
height of his future wife. The data is printed on the back of this page, in case it is no longer
stored on your calculator.
1. Use your calculator to create a scatterplot or use the scatterplots we made by hand in
class, and draw the line of best fit on the scatterplot. Be sure to label your axes with
units and at least some numbers on the axes if you are copying the plot from your
calculator.
2. Obtain the following information from your calculator and summarize it on your plot:
a. Equation of the Least Squares Regression Line (slope and intercept)
b. Correlation Coefficient (r)
c. Coefficient of Determination (r2)
d. Standard Deviation of the Residuals (s: use step 4 on page 178 to calculate this as
we did in class; you can use RESID1 STO -> L5 to store the automatically created
list of residuals into a list you can use in On-Var-Stats; this will allow you to
obtain the sum of the residuals squared). Include units!!
e. Residual Plot (Residuals vs husband’s height – do it on your calculator and sketch
it with axes labeled and scaled)
3. Write a note to Mr. Bower with your prediction for the best height of his future wife
(note: Mr. Bower is 71 inches tall). In your note, include a brief background on how you
obtained the prediction and how comfortable you are with this prediction. Back up your
prediction (and confidence level) with each of the numbers obtained in step 2; your
letter should include these values (with units) but should be interpreted in terms Mr.
Bower will understand (he has never taken a stats class!). The best letter will receive
extra credit and be delivered to Mr. Bower!
NOTE:
There is one very influential point on this graph!!
Do you think it is influencing the regression line too much, such that your
predictions will all be off? If so, best to remove that influential point, and include
your reasoning behind that in your note to Mr. Bower.
1
Go to LIST (2nd Stats) – NAMES and scroll down to find the RESID list; don’t just type in RESID!
husband height, in
69
71
69
70
65
66
70.5
67
70
71
70
72
70
69
70
70
72
70
74
73
72
70
67
79
70
wife height, in
64
68
67
62
62
65
68
64
65
68
62
67
66
67
60
63
69.5
66
65
65
66
64
66
60
64
Surname
Anderson
Tann
Hertzler
Bush
Rauch
Gehman (Dana)
Swartz
Denlinger
Histand
Wallerich
Kabakjian
Stoltzfus
Swartzentruber
Miller
Mast
Burkholder
Grega
Lambright
Mrs. Moyer
Rittenhouse
King
McTavish
Bishop
Zehr
Hunsberger