Texas Instruments TI-89 Manual Do Utilizador

Statistics and Data Plots

 546

Selecting the Calculation Type

Selecting the Calculation Type

Selecting the Calculation Type

Selecting the Calculation Type

From the Calculate dialog box (

‡), highlight the current setting for the 

 

and press 

B.

You can then select from a menu of available 
types.

One-variable statistics — Calculates the statistical variables.  

Two-variable statistics — Calculates the statistical variables. 

Cubic regression — Fits the data to the third-order 
polynomial y=ax

3

2

+cx+d. You must have at least four 

data points.

•

For four points, the equation is a polynomial fit.

•

For five or more points, it is a polynomial regression.

Exponential regression — Fits the data to the model 
equation y=ab

x 

(where a is the y-intercept) using a least-

squares fit and transformed values x and ln(y).

If an item is dimmed, 
it is not valid for the 
current Calculation 
Type.