beautypg.com

Calculating predicted values, Calculating predicted values -24 – HP 38g Graphing Calculator User Manual

Page 130

Attention! The text in this document has been recognized automatically. To view the original document, you can use the "Original mode".

background image

Calculating Predicted Values

The functions PREDX and PREDY will estimate (predict)

values for X or Y given a hypothetical value for the other. The

estimation is made based on the curve that has been

calculated to fit the data according to the specified fit.

To find

predicted

values

1. In Plot view, calculate the Fit (regression curve) for the

data set:

e In Symbolic view, your data set (S variable) must be

defined and checkmarked. In Symbolic Setup, the fit

type must be set,

e

In Plot view, press

{{FIT}}

to turn on

{{

fi

T

h

}}

and

calculate the regression curve. (If

{{FIT«}}

is already

on, press it twice to make it the current regression

equation.)

2. In Home, enter

PREDX

(y-oo/ue) [

enter

|

to find the predicted (estimated) value for the

independent variable given a hypothetical dependent

value.

® Enter

PREDY

ix-value)

to find the predicted value of

the dependent variable given a hypothetical

independent variable.

• You can type

PREDX

and

PREDY

using the Alpha shift,

or you can copy these function names from the MATH

menu under the Stat-Two category.

5-24 Statistics