TI-83 Resource Website

Statistics

Histograms
Quick Steps Step-by-Step Related Links Print Version

Very often, the focus in Statistics is not on the individual data, but the trend of the data.  The TI-83 is capable of "graphing" the individual data into a histogram (or bar graph) so that the trend of the data is easier to understand.

Before continuing this module, please see Entering Data into Lists if you have not done so already.

 

Example: Create a histogram from the following data set.  This data set denotes the number of acres on a sample of small farms in a particular county.

12 7 9 8 9
8 12 10 9 16
8 13 12 10 11
7 14 12 9 8
10 9 11 13 8

Before you begin this module, a few preliminary pieces of information need to be established:

Therefore, we will have five classes: 7 - 8, 9 - 10, 11 - 12, 13 - 14, 15 - 16.  

You should review in your Statistics course how class widths and number of classes are established.

Step 1: The data should already be entered as lists in the calculator.  Press the yellow 2ND button, then STATPLOT above the blue Y= key. 

 

 

 

Step 2: 1: PLOT 1 should be highlighted.  Press enter.  Note: You can also select the other plots using the blue arrow keys. 

Step 3: Using the blue arrow key, move the cursor to ON then press ENTER.  ON should now be highlighted.

Step 4: Now the type of graph needs to be selected -- in this case, Histogram.  Push the down blue arrow key so the cursor is now on the icon next to TYPE.  Then push the right blue arrow key so the cursor is on the bar graph icon (first row, last column).  

 
Step 5: Next, the data needs to be selected.  Use the down blue arrow key so the cursor is on L1 next to XList.  Select the list where the data is located by pressing the yellow 2ND button, then the appropriate number for the list (1 for L1, 2 for L2, etc.)

In this example, the data is stored in L1.

 
Step 6: Press the blue WINDOW screen.  The parameters of the histogram now have to be set.  
  • XMIN: the minimum value of the data.  
    In this example, it is 7.  Note: The XMIN can also be the lowest value in the first class.
  • XMAX: The maximum value of the data set.  
    In this example, it is 16.  Note: The XMAX can also be the highest value in the last class.
  • XSCL: The class width
  • YMIN: Always zero (0)
  • YMAX: This takes some guessing.  YMAX denotes the highest frequency, but it is hard to know that value just by scanning the data.  You may have to adjust this number accordingly to see the histogram clearly.
  • YSCL: Always one (1)
  • XRES: Always one (1)

 

Step 7: Press the blue GRAPH button.  The histogram should appear.

 
Step 8: Press the blue TRACE button and use the left and right blue arrow keys.  The numbers of the bottom left of the screen indicates the class and the number on the bottom right (n = ) is the number in that class -- that is, the frequency.  

In this example, there are 7 in the 7 - 8 (denoted as min=7 max<9) class.

 

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This site is maintained by Donna L. Sperry