def __init__(self, **kwargs):
from textattack.transformations import WordDeletion
transformation = WordDeletion()
super().__init__(transformation,
constraints=DEFAULT_CONSTRAINTS,
**kwargs)
def InputReductionFeng2018(model):
"""Feng, Wallace, Grissom, Iyyer, Rodriguez, Boyd-Graber. (2018).
Pathologies of Neural Models Make Interpretations Difficult.
ArXiv, abs/1804.07781.
"""
# At each step, we remove the word with the lowest importance value until
# the model changes its prediction.
transformation = WordDeletion()
constraints = [RepeatModification(), StopwordModification()]
#
# Goal is untargeted classification
#
goal_function = InputReduction(model, maximizable=True)
#
# "For each word in an input sentence, we measure its importance by the
# change in the confidence of the original prediction when we remove
# that word from the sentence."
#
# "Instead of looking at the words with high importance values—what
# interpretation methods commonly do—we take a complementary approach
# and study how the model behaves when the supposedly unimportant words are
# removed."
#
search_method = GreedyWordSwapWIR(wir_method="delete")
return Attack(goal_function, constraints, transformation, search_method)
def build(model):
# At each step, we remove the word with the lowest importance value until
# the model changes its prediction.
transformation = WordDeletion()
constraints = [RepeatModification(), StopwordModification()]
#
# Goal is untargeted classification
#
goal_function = InputReduction(model, maximizable=True)
#
# "For each word in an input sentence, we measure its importance by the
# change in the confidence of the original prediction when we remove
# that word from the sentence."
#
# "Instead of looking at the words with high importance values—what
# interpretation methods commonly do—we take a complementary approach
# and study how the model behaves when the supposedly unimportant words are
# removed."
#
search_method = GreedyWordSwapWIR(wir_method="delete")
return Attack(goal_function, constraints, transformation, search_method)