This function is only relevant when we are computing asymmetric Shapley values. For symmetric Shapley values (both regular and causal), all coalitions are allowed.
get_valid_causal_coalitions(
causal_ordering,
sort_features_in_coalitions = TRUE
)
List of vectors containing all coalitions that respects the causal ordering.
List.
Not applicable for (regular) non-causal or asymmetric explanations.
causal_ordering
is an unnamed list of vectors specifying the components of the
partial causal ordering that the coalitions must respect. Each vector represents
a component and contains one or more features/groups identified by their names
(strings) or indices (integers). If causal_ordering
is NULL
(default), no causal
ordering is assumed and all possible coalitions are allowed. No causal ordering is
equivalent to a causal ordering with a single component that includes all features
(list(1:n_features)
) or groups (list(1:n_groups)
) for feature-wise and group-wise
Shapley values, respectively. For feature-wise Shapley values and
causal_ordering = list(c(1, 2), c(3, 4))
, the interpretation is that features 1 and 2
are the ancestors of features 3 and 4, while features 3 and 4 are on the same level.
Note: All features/groups must be included in the causal_ordering
without any duplicates.
Boolean. If TRUE
, then the feature indices in the
coalitions are sorted in increasing order. If FALSE
, then the function maintains the
order of features within each group given in causal_ordering
.
Lars Henry Berge Olsen