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\(P(Y=y | do(X=x)) = \sum_z P(Y=y | X=x, Z=z) P(Z=z)\). Each stratum is reweighted by how common it is in the whole population, not among the treated; that reweighting is the entire content of the formula.

Usage

morie_backdoor_adjustment(x, y, z, at = NULL)

Arguments

x, y

Discrete treatment and outcome vectors.

z

Adjustment set: a vector or a matrix of columns.

at

Treatment value to intervene on; defaults to every level.

Value

Named list with distribution, strata, p_z, n, incomplete_strata, method.

Details

This is causal only when Z satisfies the back-door criterion, which is a claim about the graph and cannot be checked from data. See morie_backdoor_criterion. All variables are discrete.

Mirrors morie.fn.bdrj.

References

Pearl J (2009). Causality, 2nd edn, Thm 3.3.2.

Examples

morie_backdoor_adjustment(c(1, 1, 0, 0), c(1, 0, 1, 0), c(0, 0, 1, 1))$distribution
#> $`0`
#>    0    1 
#> 0.25 0.25 
#> 
#> $`1`
#>    0    1 
#> 0.25 0.25 
#>