Complete the following steps to specify the response and the expectation
function.
In
Response,
enter the column of numeric data that you want to explain or predict. The
response is also called the Y variable.
In
Expectation Function,
enter the function that describes the relationship between the predictors and
the expected response value using one of the following methods:
Use Catalog:
Click to choose a predefined function. For more information, see the section on
Use catalog.
Use Calculator:
Click to use the calculator to enter a custom function. For more information,
see the section on Use calculator.
Edit directly:
Enter the function directly into the text box.
In this worksheet, Expansion
is the response variable. Kelvin is
the predictor variable and appears in the expectation function. The expectation
function that describes the relationship between the response and predictor is
(Theta1+Theta2*Kelvin+Theta3*Kelvin^2+Theta4*Kelvin^3)/(1+Theta5*Kelvin+Theta6*Kelvin^2+Theta7*Kelvin^3).
C1
C2
Expansion
Kelvin
0.591
24.41
1.547
34.82
2.902
44.09
2.894
45.07
Use Catalog
Select a predefined expectation function.
Show functions
Select a category to filter the list of functions. You can narrow down
the functions to make it easier to find the one you want.
Function
Select an expectation function. You can select a function that is
supplied by Minitab or a custom function that you have previously entered.
Minitab automatically adds a custom function to the catalog when you first use
it to perform a nonlinear regression analysis. After you choose a function and
click
OK,
Minitab prompts you to choose predictors for each placeholder.
Choose predictors
Minitab automatically lists the placeholder that it detects
within the expectation function. Enter the column that contain the actual
predictor variable for each placeholder.
Manage My Functions
You can rename, assign a category, or delete custom functions in the
catalog. Each time you perform nonlinear regression with a new custom function,
Minitab adds the function to the catalog and assigns it a default name and
category. Use the features in this dialog box to improve how the catalog
displays and filters the custom functions.
Use Calculator
Use the calculator to enter an expectation function that contains arithmetic
operations, comparison operations, logical operations, functions, and column
operations. Expressions may include columns, stored constants, numbers,
operations, and functions, but not matrices. For more information, go to
How to specify the expectation function in nonlinear regression.
Expectation function
Enter the mathematical function that you want Minitab to use for the
nonlinear regression. Select variables, buttons, and functions to create your
expression. For more information, go to
Create
a formula with the
Calculator.
Functions
Select a category of calculator functions to filter the list of
functions. For more information, go to
Calculator
Functions.