Exploratory Data Analysis: Boxplots on the TI-82/83
Data: Pulse rates (number of beats per minute) of 20 male college students:
82 74 77 62 78 58 85 74 66 71
58 80 65 60 54 75 71 74 73 82
First enter the data into a statistical list:
|
STAT |
ENTER |
Clear list of previous data (if any) by moving the cursor to the top of the list so the title L1 is black.
Keys to Clear a Statistics Register:
|
^ |
CLEAR |
ENTER |
Type in the data, pressing ENTER until all 20 scores are entered.
Example:
|
82 |
ENTER |
74 |
ENTER |
77 |
ENTER |
Leave the Statistical Register.
|
2nd |
Quit |
Go into STAT PLOT
|
2nd |
STATPLOT |
1 |
Turn the Stat Plot ON: Blinking cursor must be on word ON.
Press ENTER
You must select the Boxplot symbol:
|
V |
> |
> |
> |
> |
ENTER |
Verify that the correct data list is showing. This data is in list L1. You can modify this list number by pressing 2nd L2, for example. You will find the "L2" above the "2" key on the calculator front.
The frequency ("Freq") should have a "1" because each number in our list represents one piece of data from our experiment.
Now you are ready to graph the plot.
First, turn off or delete any functions you have typed in the graphing list:
|
Y = |
CLEAR |
ENTER |
2nd |
Quit |
The calculator will set your viewing window to the correct size that fits the data you typed in List L1 if you press the following keys for a "ZoomStat".
|
ZOOM |
9 |
Determine the five statistical values for the plot by pressing the following:
|
TRACE |
Med = 73.5
|
> |
Q3 = 77.5
|
> |
Max x = 85
|
< |
< |
< |
Q1 = 63.3
|
< |
Min x = 54
One final word:
Turn the Stat Plot function off by pressing the following keys:
|
2nd |
STAT PLOT |
4 |
ENTER |
Happy BoxPlotting!!
Nan Burwell, Math Dept., Pellissippi State Community College