It's Data Time!

 

In this lesson, you will learn how to put data in your TI calculator and how to calculate the basic statistics.

 

First, some review.

 

MEAN:  Better known as the average.  You add up all of the data and then divide by how many data numbers there were.  The symbol for the mean is the letter x with a bar on top of it.

 

MEDIAN:  Better know as the center of the data.  You take your data and put all of the numbers in order.  You then split the data in half, and the number that is in the middle is the Median.  If there is no single middle number, you take the two middle numbers and find the average of them.

 

Let us say that this is a person's set of quiz scores:

 

                     6, 7, 5, 8, 7, 9, 10, 6, 8, 5

 

Find the mean and median of the data by doing the old fashon way.

 

 

Now, let us use the calcuator.

 

The button you will use most in this course is the STAT key.  You will find it under the DEL key.  Press it once.  Select 1:Edit. . . .   This will take you to a screen that has columns with L1, L2, etc on the top.  Hopefully, the columns do not have any numbers in them.

 

Each column is like a spread sheet.  In column L1, type in the 10 numbers from above.  Press ENTER after each one to move down to the next slot.

 

After entering all 10 numbers, hit STAT again, but this time use the right arrow key to move the cursor to CALC.  Select 1: 1-Var Stats.  This will put the words 1-Var Stats on the main screen.  Next you are going to type in L1 (that is the column the numbers are in) by typing (2nd) 1.   Hit ENTER.

 

You will now get a screen that has 1-Var Stats on the top and a whole lot of other stuff below.  The first thing on the list is x-bar, which is the mean and, if all went well, should be the same as what you got earlier.  Next, use the down arrow to scroll down and before long you will see Med, which is the median number.  Does it match your earlier answer?

 

We will learn what the rest of the numbers on the screen mean as we go along.  But for now, if you got the same answers with the calculator as you did the long way, then all is well.

 

To clear your numbers, Type STAT,  Select 1: Edit . .,  Move the cursor all the way up until it is covering the L1.  Then hit Clear, then Enter.   NEVER HIT DELETE TO CLEAR OUT A COLUMN!!

 

This simple procedure, which by the way will be the first "calculator procedure skill" you will need, is the most fundamental skill for the class.