HP Prime Graphing NW280AAABA manual Defining a regression model, Fit types

Defining a regression model

You define a regression model in Symbolic view. There are three ways to do so:

•Accept the default option to fit the data to a straight line.

•Choose a pre-defined fit type (logarithmic, exponential, and so on).

•Enter your own mathematical expression. The expression will be plotted so that you can see how closely it fits the data points.

Choose a fit

Fit types

1.PressYto display the Symbolic view.

2.For the analysis you are interested in (S1 through S5), select the Type field.

3.Tap the field again to see the menu of fit types.

4.Select your preferred fit type from the menu. (See “Fit types” on page 231.)

Twelve fit types are available:

Fit type	Meaning
Linear	(Default.) Fits the data to a
	straight line: y = mx+b. Uses a
	least-squares fit.
Logarithmic	Fits the data to a logarithmic
	curve: y = m lnx + b.
Exponential	Fits the data to the natural	e	mx	.
	exponential curve: y = b ⋅
Power	Fits the data to a power curve:
	. y = b ⋅ xm .
Exponent	Fits the data to an exponential
	curve: y = b ⋅ mx .
Inverse	Fits the data to an inverse
	m
	variation: y = --- + b
	x

Statistics 2Var app 231