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Analyzing one-variable statistics, Analyzing two-variable statistics, Computing values automatically – Texas Instruments Calculator User Manual

Page 71: Using x' and y' for regression predictions, Regression models

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Statistics Worksheet

67

When you enter data for one-variable statistics,

X

nn represents the

value and

Y

nn specifies the number of occurrences (frequency).

When you enter a value for

X

nn, the value for

Y

nn defaults to 1.

Analyzing One-Variable Statistics

To analyze one-variable statistics, select

1-V

. Only values for

n

,

v,

Sx

,

s

X

,

G

X

, and

G

X

2

are computed and displayed for one-variable statistics.

Analyzing Two-Variable Statistics

You can choose from among these four regression-analysis methods:

LIN

Ln

EXP

PWR

Computing Values Automatically

Except for the predicted

X'

and

Y'

values, the calculator computes and

displays values for statistics variables automatically when you access
them.

Using X' and Y' for Regression Predictions

To use the

X'

and

Y'

variables for regression predictions, you either can

enter a value for

X'

to compute

Y'

or enter a value for

Y'

to compute

X'

.

Regression Models

For two-variable data, the Statistics worksheet uses four regression
models for curve fitting and forecasting.

The calculator interprets the

X

value as the independent variable and the

Y

value as the dependent variable.

The calculator computes the statistical results using these transformed
values:

LIN

uses X and Y.

Model

Formula

Restrictions

LIN

Y = a + b X

None

Ln

Y = a + b ln(X)

All X values > zero

EXP

Y = a b

x

All Y values > zero

PWR

Y = a X

b

All X and Y values > zero