setx {Zelig}R Documentation

Setting Explanatory Variable Values

Description

The setx command uses the variables identified in the formula generated by zelig and sets the values of the explanatory variables to the selected values. Use setx after zelig and before sim to simulate quantities of interest.

Usage

x.out <- setx(object, fn = mean, data = NULL, cond = FALSE, ...)

Arguments

object the saved output from zelig.
fn a function applied to all non-factor variables. The default function is mean. The default value for factor variables corresponds to the value of the greatest mode. When more than one such mode exists, the smallest value in Levels is selected. Setting fn = median changes the value for the non-factor variables to their medians, and factor variables may be set by specifying exact variables.
data a new data frame used to set the values of explanatory variables. If data = NULL (the default), the data frame called in zelig is used.
cond a logical value indicating whether unconditional (default) or conditional (choose cond = TRUE) prediction should be performed. If you choose cond = TRUE, setx will ignore the arguments in fn and ....
... user-defined values of specific variables overwriting the default values set by the function fn. For example, adding var1 = mean(data\$var1) or x1 = 12 explicitly sets the value of x1 to 12. In addition, you may specify one explanatory variable as a range of values, creating one observation for every unique value in the range of values.

Author(s)

Kosuke Imai <kimai@princeton.edu>; Gary King <king@harvard.edu>; Olivia Lau <olau@fas.harvard.edu>

See Also

The full Zelig manual may be accessed online at http://gking.harvard.edu/zelig.


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