© 1999 T
EXAS
I
NSTRUMENTS
I
NCORPORATED
TI-30X
Ù
S: A Guide for Teachers
24
WNBA Stats — 2-Variable Statistics
(
Continued)
3. Calculate the statistical data.
You may want to fix the decimal to 2 places
before doing the statistical calculations.
1. Press
%
‚
.
F 0 1 2 3 4 5 6 7 8 9
2. Press
2
.
Ask students:
•
What is the average points scored for the
players shown?
•
What is the average playing time?
•
What is the total number of points scored
per game for all the given players?
You may want to discuss the other statistical
variables and what they mean.
1. Press
u
.
n
Ï
Sx
Î
x
Ð
12.00
2. Press
"
to
Ï
.
n
Ï
Sx
Î
x
Ð
9.33
3. Press
"
"
"
to
Ð
.
n
Ï
Sx
Î
x
Ð
21.59
4. Press
"
"
"
to
Ò
x.
Sy
Î
y
Ò
x
112.00
4. The form of the equation is
y = ax + b
. Write
the equation for the line of best fit (round to
the nearest hundredth).
1.56
x
+ 7.02
5. The closer the correlation coefficient value is
to 1 (or 1), the better the correlation
between the two variables. Write the
correlation coefficient.
r
= .91
1. Press
"
until you get to a.
This is the slope of the line of
best fit.
Ò
XY a b r
1.56
2. Press
"
to
b
. This is the
y-intercept of the line.
Ò
XY a b r
7.02
3. Press
"
to
r
. This is the
correlation coefficient.
Ò
XY a b r
0.91
6. Now calculate how many minutes you would
expect a player to play if she averages 15
points per game.
1. Press
"
"
to
y
¢
.
x
¢
y
¢
2. Press
<
.
3. Type
15
E
and press
<
.
y
¢
(15)
30.44