WORKING WITH THE TI-89

          

   

      

We will be using the following statistical features of the TI-89:

Stats/List Editor

When you select the Stats/List Editor icon, click ENTER.

You must see a group of lists named:  list1, list2, list3,....

 

To enter data in a list:

To enter the data in the selected list, place the cursor below the list name using the left(right) or up(down) arrows.

Type the entries in the list, following each value with ENTER

 

To create a new list , in addition to the 6 default lists:

If you want to create a new list, place the cursor on any of the list names (list1, list2,...) and move the cursor to the right until you find a blank column.        

Type the name you want for the new list, then click ENTER.

To enter the data in the selected list, place the cursor below the list name using the left(right) or up(down) arrows.

Type the entries in the list, following each value with ENTER.

 

To delete a list,

Put the cursor at the title of list 

Press simultaneously the two buttons :(GreenButton) and (DEL)

 

To access a list of names : Use 2nd → VAR LINK (same button as subtraction)

To sort the data in a given list in ascending(increasing) order,

Put the cursor at the title of list 

Click F3

Select 2:Ops

Press ENTER

Select 1:Sort List

You should see the name of the selected list. If you do not see it, you have to find the list you want sorted using :2nd → VAR LINK 

Press ENTER

 

To sort the data in a given list in descending(decreasing) order,

Put the cursor at the title of list 

Click F3

Select 2:Ops

Press ENTER

Select 1:Sort List

You should see the name of the selected list. If you do not see it, you have to find the list you want sorted using :2nd → VAR LINK 

Press ENTER

Under the list name you will see the option Sort Order :

Now select Descending (the Ascending order is the default!) 

 

 To Clear a list:

Put the cursor at the title of list 

Click CLEAR

Press ENTER

 

F4-CALC

 

Use this option to get one or two variable summary statistics, the correlation coefficient, linear regression coefficients (slope and y-intercept), and regression  using transformed variables.

 

1:1-Var Stats: Use this option to compute summary statistics for one-variable (univariate) data. It gives the number of observations(n), mean(X), sum(Σ X), sum of squares (Σ X2), sample standard deviation (Sx), population standard deviation (σ), median(m), quartiles (Q1 and Q3), minimum, and maximum.

 

2:2-Var Stats: Use this option to compute summary statistics for bivariate data. It gives the number of pairs of observations (n), mean(X, Y), sum(ΣX , ΣY),   sum    of squares   (Σ X2  , ΣY2), sample standard deviation (Sx, Sy),   population   standard    deviation (σx , σy), min and max for each variable, and sum of products (ΣXY).

 

3:Regressions: Use this option to get the correlation coefficient and least squares estimates for slope and y-intercept for linear regression.

 

8:ExpReg: Use this option for exponential transformation to linearize a regression model.

 

9:PowerReg: Use this option for fitting a power model using logarithmic transformation to linearize a regression model.

 

F6.-TESTS

 

We will talk about these options after we have learnt about Statistical Inference.

 

STAT PLOT:

Use this option to make a scatterplot, boxplot, histogram, regression line plot, and residual plot.

 

MAKING A HISTOGRAM USING THE ENTIRE DATA SET:

  1. Enter the data in one of the lists.(OtherList)
  2. Click F2-Plots 
  3. Select 1:Plot Setup
  4. Click F1:Define
  5. Select Plot Type: Out of 5 available choices, select 4:Histogram
  6. Select the list with the data using: 2nd → VAR LINK 
  7. Click ENTER 
  8. Click ENTER .(Now you should see the Plot 1 option checked!)
  9. Click the GreenButton and F3
  10. If you do not see the histogram, Click F2-Zoom button and select 9:ZoomData

MAKING A BOXPLOT :

  1. Enter the data in one of the lists.(OtherList)
  2. Click F2-Plots 
  3. Select 1:Plot Setup
  4. Click F1:Define
  5. Select Plot Type: Out of 5 available choices, select 3:BoxPlot
  6. Select the list with the data using: 2nd → VAR LINK 
  7. Click ENTER 
  8. Click ENTER .(Now you should see the Plot 1 option checked!)
  9. Click the GreenButton and F3
  10. If you do not see the histogram, Click F2-Zoom button and select 9:ZoomData

 

PARAMETERS OF A DISTRIBUTION OF UNIVARIATE (one variable!) DATA

Click F4-Calc

Select 1:1-Var Stats

Press ENTER

Press  2nd → LIST to select the list with the data

Select the list with the data

Press ENTER

You should see a window with all the results of the calculations

 

WORKING WITH BIVARIATE (two variables!) DATA:

 

TO MAKE A SCATTERPLOT:

  1. Enter data (X values) in one of the lists (let's say...ListA)
  2. Enter data (Y values) in another list. (let's say...ListB)
  3. Click F2-Plots 
  4. Select 1:Plot Setup
  5. Click F1:Define
  6. Select Plot Type: Out of 5 available choices, select 1:Scatter
  7. Select the list with the X variable data using: 2nd → VAR LINK 
  8. Click ENTER 
  9. Select the list with the Y variable data using: 2nd → VAR LINK 
  10. Click ENTER 
  11. Click ENTER again
  12. Click ENTER .(Now you should see the Plot 1 option checked!)
  13. Click the GreenButton and F3
  14. If you do not see the histogram, Click F2-Zoom button and select 9:ZoomData. You should see the scatter plot.

 

 

  TO COMPUTE THE CORRELATION COEFFICIENT:

  1. Enter data (X values) in one of the lists (let's say...ListA)
  2. Enter data (Y values) in another list. (let's say...ListB)
  3. Click F4-Calc 
  4. Select 1:LinReg(a+bx)
  5. Select the list with the X variable data using: 2nd → VAR LINK 
  6. Click ENTER 
  7. Select the list with the Y variable data using: 2nd → VAR LINK 
  8. Click ENTER 
  9. Click ENTER again
  10. Select where to store the regression equations Select Y1(x)
  11. Click ENTER
  12. You should see the linear equation and the values of the parameters a, b, r2 and r.

 

TO GET SUMMARY STATISTICS FOR BIVARIATE( two variables!!) DATA

 

  1. Enter data (X values) in one of the lists (let's say...ListA)
  2. Enter data (Y values) in another list. (let's say...ListB)
  3. Click F4-Calc 
  4. Select 2:2-Var Stats
  5. Select the list with the X variable data using: 2nd → VAR LINK
  6. Click ENTER
  7. Select the list with the Y variable data using: 2nd → VAR LINK
  8. Click ENTER
  9. Click ENTER again
  10. You should a summary of all the statistics associated with the variables X and Y.

 

 

TO CALCULATE RESIDUALS:

           The TI-89 calculator, creates automatically a new list called resid with the residuals for the calculated Y1(X) function.

 

TO TRANSFORM DATA

  1.  Create a new list with a name associated with the transformation.for ex. LnList if you are transforming the data using the logarithmic (ln) function..

  2.  Put the cursor at the title of the new list LnList

  3.  Enter the function you want to use, for ex. ln(),

  4. The argument of the function should be the name of the list where you have the data to be transformed. For ex: ln(ListA)

  5. Press ENTER

     

WORKING WITH RANDOM NUMBERS

         To work with the random generator randInt, follow these instructions:

  • Click the CATALOG key

  • Click  F3

  • Select  randInt(

  • To get 100 random numbers between 1 and 6, type the instruction : randInt(1, 6,100) STO L1ST1

  • The last part of the instruction, STO LIST1, save the 100 random numbers into the list LIST1.

  • If you need to sort the data, press the button APPS

  • Go to STAT/List Editor

  • Click F3

  • Select 2 Ops

  • Then, select Sort List

  • Now, you have to specify the list with the data, in this case LIST1

  • You can select the list using 2nd VAR LINK