This dialog is used to specify a linear model to be fit by the
The left model-formula box specifies the response variable to be used in the model; it
may be a variable name or an expression evaluating to the response variable, such as
The right model-formula box specifies the right-hand (i.e., predictor) side of the model.
lm for details.
You can type directly in the model formula boxes. Alternatively, double-clicking the left mouse
button on a variable in the variable-list transfers it to the left-hand side of the model (if
it is empty or selected) or to the right-hand side. You can also enter operators and parentheses using the buttons
above the formula. If you select several variables in the variable-list box, clicking on the
: button will enter them into the model formula.
Specifying a subset expression allows you to fit the model to a subset of observations
in the active data set. For example, assuming that
gender is a variable in the
active data set, entering
gender == "Male" would restrict the model to males.
If the active model is a linear model and the active data set has not changed, then the initial values of the left-hand-side, right-hand-side, and subset fields are retained from the previous model.
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