The structure of an object of S3 class bn.strength.
An object of class bn.strength is a data frame with the following
columns (one row for each arc):
from, to: the nodes incident on the arc.
strength: the strength of the arc. See
arc.strength, boot.strength,
custom.strength and strength.plot
for details.
and some additional attributes:
method: a character string, the method used to compute the
strength coefficients. It can be equal to test, score or
bootstrap.
threshold: a numeric value, the threshold used to determine
if a strength coefficient is significant.
An optional column called direction may also be present, giving the
probability of the direction of an arc given its presence in the graph.
Only the plot() method is defined for this class; therefore, it can
be manipulated as a standard data frame.