class BasePerceptronRanker(Ranker):
def __init__(self, cfg):
if not cfg:
cfg = {}
self.passes = cfg.get('passes', 5)
self.alpha = cfg.get('alpha', 1)
self.language = cfg.get('language', 'en')
self.selector = cfg.get('selector', '')
# initialize diagnostics
self.lists_analyzer = None
self.evaluator = None
self.prune_feats = cfg.get('prune_feats', 1)
self.rival_number = cfg.get('rival_number', 10)
self.averaging = cfg.get('averaging', False)
self.randomize = cfg.get('randomize', False)
self.future_promise_weight = cfg.get('future_promise_weight', 1.0)
self.future_promise_type = cfg.get('future_promise_type', 'expected_children')
self.rival_gen_strategy = cfg.get('rival_gen_strategy', ['other_inst'])
self.rival_gen_max_iter = cfg.get('rival_gen_max_iter', 50)
self.rival_gen_max_defic_iter = cfg.get('rival_gen_max_defic_iter', 3)
self.rival_gen_beam_size = cfg.get('rival_gen_beam_size')
self.rival_gen_prune_size = cfg.get('rival_gen_prune_size')
self.candgen_model = cfg.get('candgen_model')
self.diffing_trees = cfg.get('diffing_trees', False)
def score(self, cand_tree, da):
"""Score the given tree in the context of the given dialogue act.
@param cand_tree: the candidate tree to be scored, as a TreeData object
@param da: a DA object representing the input dialogue act
"""
return self._score(self._extract_feats(cand_tree, da))
def score_all(self, cand_trees, da):
"""Array version of the score() function"""
return [self.score(cand_tree, da) for cand_tree in cand_trees]
def _extract_feats(self, tree, da):
raise NotImplementedError
def train(self, das_file, ttree_file, data_portion=1.0):
"""Run training on the given training data."""
self._init_training(das_file, ttree_file, data_portion)
for iter_no in xrange(1, self.passes + 1):
self.train_order = range(len(self.train_trees))
if self.randomize:
rnd.shuffle(self.train_order)
log_info("Train order: " + str(self.train_order))
self._training_pass(iter_no)
if self.evaluator.tree_accuracy() == 1: # if tree accuracy is 1, we won't learn anything anymore
break
# averaged perceptron – average the weights obtained after each pass
if self.averaging is True:
self.set_weights_iter_average()
def _init_training(self, das_file, ttree_file, data_portion):
"""Initialize training (read input data, fix size, initialize candidate generator
and planner)"""
# read input
log_info('Reading DAs from ' + das_file + '...')
das = read_das(das_file)
log_info('Reading t-trees from ' + ttree_file + '...')
ttree_doc = read_ttrees(ttree_file)
sents = sentences_from_doc(ttree_doc, self.language, self.selector)
trees = trees_from_doc(ttree_doc, self.language, self.selector)
# make training data smaller if necessary
train_size = int(round(data_portion * len(trees)))
self.train_trees = trees[:train_size]
self.train_das = das[:train_size]
self.train_sents = sents[:train_size]
self.train_order = range(len(self.train_trees))
log_info('Using %d training instances.' % train_size)
# initialize candidate generator
if self.candgen_model is not None:
self.candgen = RandomCandidateGenerator.load_from_file(self.candgen_model)
# self.sampling_planner = SamplingPlanner({'language': self.language,
# 'selector': self.selector,
# 'candgen': self.candgen})
# check if A*search planner is needed (i.e., any rival generation strategy requires it)
# and initialize it
if isinstance(self.rival_gen_strategy[0], tuple):
asearch_needed = any([s in ['gen_cur_weights', 'gen_update']
for _, ss in self.rival_gen_strategy
for s in ss])
else:
asearch_needed = any([s in ['gen_cur_weights', 'gen_update']
for s in self.rival_gen_strategy])
if asearch_needed:
assert self.candgen is not None
self.asearch_planner = ASearchPlanner({'candgen': self.candgen,
'language': self.language,
'selector': self.selector,
'ranker': self, })
def _training_pass(self, pass_no):
"""Run one training pass, update weights (store them for possible averaging),
and store diagnostic values."""
pass_start_time = time.time()
self.reset_diagnostics()
self.update_weights_sum()
log_debug('\n***\nTR %05d:' % pass_no)
rgen_max_iter = self._get_num_iters(pass_no, self.rival_gen_max_iter)
rgen_max_defic_iter = self._get_num_iters(pass_no, self.rival_gen_max_defic_iter)
rgen_beam_size = self.rival_gen_beam_size
rgen_prune_size = self.rival_gen_prune_size
rgen_strategy = self._get_rival_gen_strategy(pass_no)
for tree_no in self.train_order:
log_debug('TREE-NO: %d' % tree_no)
log_debug('SENT: %s' % self.train_sents[tree_no])
gold = Inst(da=self.train_das[tree_no],
tree=self.train_trees[tree_no],
score=self._score(self.train_feats[tree_no]),
feats=self.train_feats[tree_no])
# obtain some 'rival', alternative incorrect candidates
for strategy in rgen_strategy:
# generate using current weights
if strategy == 'gen_cur_weights':
gen = self._gen_cur_weights(gold, rgen_max_iter, rgen_max_defic_iter,
rgen_prune_size, rgen_beam_size)
# generate while trying to update weights
elif strategy == 'gen_update':
gen = self._gen_update(gold, rgen_max_iter, rgen_max_defic_iter,
rgen_prune_size, rgen_beam_size)
# check against other possible candidates/combinations
else:
gen = self._get_rival_candidates(gold, tree_no, strategy)
# evaluate the top-scoring generated tree against gold t-tree
# (disregarding whether it was selected as the best one)
self.evaluator.append(TreeNode(gold.tree), TreeNode(gen.tree), gold.score, gen.score)
# update weights if the system doesn't give the highest score to the gold standard tree
if gold.score < gen.score:
self._update_weights(gold, gen)
# store a copy of the current weights for averaging
self.store_iter_weights()
# debug print: current weights and pass accuracy
log_debug(self._feat_val_str(), '\n***')
log_debug('PASS ACCURACY: %.3f' % self.evaluator.tree_accuracy())
# print and return statistics
self._print_pass_stats(pass_no, datetime.timedelta(seconds=(time.time() - pass_start_time)))
def diffing_trees_with_scores(self, da, good_tree, bad_tree):
"""For debugging purposes. Return a printout of diffing trees between the chosen candidate
and the gold tree, along with scores."""
good_sts, bad_sts = good_tree.diffing_trees(bad_tree, symmetric=False)
comm_st = good_tree.get_common_subtree(bad_tree)
ret = 'Common subtree: %.3f' % self.score(comm_st, da) + "\t" + unicode(comm_st) + "\n"
ret += "Good subtrees:\n"
for good_st in good_sts:
ret += "%.3f" % self.score(good_st, da) + "\t" + unicode(good_st) + "\n"
ret += "Bad subtrees:\n"
for bad_st in bad_sts:
ret += "%.3f" % self.score(bad_st, da) + "\t" + unicode(bad_st) + "\n"
return ret
def _get_num_iters(self, cur_pass_no, iter_setting):
"""Return the maximum number of iterations (total/deficit) given the current pass.
Used to keep track of variable iteration number setting in configuration.
@param cur_pass_no: the number of the current pass
@param iter_setting: number of iteration setting (self.max_iter or self.max_defic_iter)
"""
if isinstance(iter_setting, (list, tuple)):
ret = 0
for set_pass_no, set_iter_no in iter_setting:
if set_pass_no > cur_pass_no:
break
ret = set_iter_no
return ret
else:
return iter_setting # a single setting for all passes
def _get_rival_gen_strategy(self, cur_pass_no):
"""Return the rival generation strategy/strategies for the current pass.
Used to keep track of variable rival generation setting setting in configuration.
@param cur_pass_no: the number of the current pass
"""
if isinstance(self.rival_gen_strategy[0], tuple):
ret = []
for set_pass_no, strategies in self.rival_gen_strategy:
if set_pass_no > cur_pass_no:
break
ret = strategies
return ret
else:
return self.rival_gen_strategy # a single setting for all passes
def _print_pass_stats(self, pass_no, pass_duration):
"""Print pass statistics from internal evaluator fields and given pass duration."""
log_info('Pass %05d -- tree-level accuracy: %.4f' % (pass_no, self.evaluator.tree_accuracy()))
log_info(' * Generated trees NODE scores: P: %.4f, R: %.4f, F: %.4f' %
self.evaluator.p_r_f1())
log_info(' * Generated trees DEP scores: P: %.4f, R: %.4f, F: %.4f' %
self.evaluator.p_r_f1(EvalTypes.DEP))
log_info(' * Gold tree BEST: %.4f, on CLOSE: %.4f, on ANY list: %.4f' %
self.lists_analyzer.stats())
log_info(' * Tree size stats:\n -- GOLD: %s\n -- PRED: %s\n -- DIFF: %s' %
self.evaluator.size_stats())
log_info(' * Common subtree stats:\n -- SIZE: %s\n -- ΔGLD: %s\n -- ΔPRD: %s' %
self.evaluator.common_substruct_stats())
log_info(' * Score stats\n -- GOLD: %s\n -- PRED: %s\n -- DIFF: %s'
% self.evaluator.score_stats())
log_info(' * Duration: %s' % str(pass_duration))
def _feat_val_str(self, sep='\n', nonzero=False):
"""Return feature names and values for printing. To be overridden in base classes."""
return ''
def _get_rival_candidates(self, gold, tree_no, strategy):
"""Generate some rival candidates for a DA and the correct (gold) tree,
given a strategy; using other DAs for the correct tree, other trees for the correct
DA, or random trees.
NB: This has not been shown to be usable in practice; use _gen_cur_weights() instead.
TODO: checking for trees identical to the gold one slows down the process
@param tree_no: the index of the current training data item (tree, DA)
@rtype: tuple of two lists: one of TreeData's, one of arrays
@return: an array of rival trees and an array of the corresponding features
"""
train_trees = self.train_trees
rival_das, rival_trees, rival_feats = [], [], []
if strategy != 'other_da':
rival_das = [gold.da] * self.rival_number
# use current DA but change trees when computing features
if strategy == 'other_inst':
# use alternative indexes, avoid the correct one
rival_idxs = map(lambda idx: len(train_trees) - 1 if idx == tree_no else idx,
rnd.sample(xrange(len(train_trees) - 1), self.rival_number))
other_inst_trees = [train_trees[rival_idx] for rival_idx in rival_idxs]
rival_trees.extend(other_inst_trees)
rival_feats.extend([self._extract_feats(tree, gold.da) for tree in other_inst_trees])
# use the current gold tree but change DAs when computing features
if strategy == 'other_da':
rival_idxs = map(lambda idx: len(train_trees) - 1 if idx == tree_no else idx,
rnd.sample(xrange(len(train_trees) - 1), self.rival_number))
other_inst_das = [self.train_das[rival_idx] for rival_idx in rival_idxs]
rival_das.extend(other_inst_das)
rival_trees.extend([self.train_trees[tree_no]] * self.rival_number)
rival_feats.extend([self._extract_feats(self.train_trees[tree_no], da)
for da in other_inst_das])
# # candidates generated using the random planner (use the current DA)
# if strategy == 'random':
# random_trees = []
# while len(random_trees) < self.rival_number:
# tree = self.sampling_planner.generate_tree(da)
# if (tree != train_trees[tree_no]): # don't generate trees identical to the gold one
# random_trees.append(tree)
# rival_trees.extend(random_trees)
# rival_feats.extend([self._extract_feats(tree, da) for tree in random_trees])
# score them along with the right one
rival_scores = [self._score(r) for r in rival_feats]
top_rival_idx = rival_scores.index(max(rival_scores))
gen = Inst(tree=rival_trees[top_rival_idx],
da=rival_das[top_rival_idx],
score=rival_scores[top_rival_idx],
feats=rival_feats[top_rival_idx])
# debug print: candidate trees
log_debug('#RIVALS: %02d' % len(rival_feats))
log_debug('SEL: GOLD' if gold.score >= gen.score else ('SEL: RIVAL#%d' % top_rival_idx))
log_debug('ALL CAND TREES:')
for ttree, score in zip([gold.tree] + rival_trees, [gold.score] + rival_scores):
log_debug("%12.5f" % score, "\t", ttree)
return gen
def _gen_cur_weights(self, gold, max_iter, max_defic_iter, prune_size, beam_size):
"""
Get the best candidate generated using the A*search planner, which uses this ranker with current
weights to guide the search, and the current DA as the input.
@param gold: the gold-standard Inst holding the input DA for generation and the reference tree
@param max_iter: maximum number of A*-search iterations to run
@param max_defic_iter: maximum number of deficit A*-search iterations (stopping criterion)
@param prune_size: beam size for open list pruning
@param beam_size: beam size for candidate expansion (expand more per iteration if > 1)
@return: The best generated tree that is different from the gold-standard tree
@rtype: Inst
"""
log_debug('GEN-CUR-WEIGHTS')
# TODO make asearch_planner remember features (for last iteration, maybe)
self.asearch_planner.run(gold.da, max_iter, max_defic_iter, prune_size, beam_size)
return self.get_best_generated(gold)
def get_best_generated(self, gold):
"""Return the best generated tree that is different from the gold-standard tree
(to be used for updates, if it scores better). Also, keep track of logging and
update analyzer lists.
@param gold: the gold-standard Inst from which the generated tree must differ
@rtype: Inst
"""
self.lists_analyzer.append(gold.tree,
self.asearch_planner.open_list,
self.asearch_planner.close_list)
gen_tree = gold.tree
while self.asearch_planner.close_list and gen_tree == gold.tree:
gen_tree, gen_score = self.asearch_planner.close_list.pop()
# scores are negative on the close list – reverse the sign
gen = Inst(tree=gen_tree, da=gold.da, score=-gen_score,
feats=self._extract_feats(gen_tree, gold.da))
log_debug('SEL: GOLD' if gold.score >= gen.score else 'SEL: GEN')
log_debug("GOLD:\t", "%12.5f" % gold.score, "\t", gold.tree)
log_debug("GEN :\t", "%12.5f" % gen.score, "\t", gen.tree)
return gen
def _gen_update(self, gold, max_iter, max_defic_iter, prune_size, beam_size):
"""Try generating using the current weights, but update the weights after each
iteration if the result is not going in the right direction (not a subtree of the
gold-standard tree).
@param gold: the gold-standard Inst holding the input DA for generation and the reference tree
@param max_iter: maximum number of A*-search iterations to run
@param max_defic_iter: maximum number of deficit A*-search iterations (stopping criterion)
@param prune_size: beam size for open list pruning
@param beam_size: beam size for candidate expansion (expand more per iteration if > 1)
@return: The best generated tree that is different from the gold-standard tree
@rtype: Inst
"""
log_debug('GEN-UPDATE')
self.asearch_planner.init_run(gold.da, max_iter, max_defic_iter, prune_size, beam_size)
while not self.asearch_planner.check_finalize():
# run one A*search iteration
self.asearch_planner.run_iter()
# stop if there's nothing on the open list
if not self.asearch_planner.open_list:
break
# look if we are on the right track to the gold tree
cur_top, score = self.asearch_planner.open_list.peek()
csi, _ = gold.tree.common_subtree_idxs(cur_top)
# if not, update
if len(csi) != len(cur_top):
feats = self._extract_feats(cur_top, gold.da)
gen = Inst(tree=cur_top, da=gold.da, feats=feats, score=score)
# for small wrong trees,
# fake the current open list to only include a subtree of the gold tree
# TODO fake it better, include more variants
# update using a subtree of the gold tree
if len(cur_top) < len(gold.tree):
diff = sorted(list(set(range(len(gold.tree))) - set(csi)),
cmp=gold.tree._compare_node_depth)
gold_sub = gold.tree.get_subtree(csi + diff[0:len(cur_top) - len(gold.tree)])
self.asearch_planner.open_list.clear()
self.asearch_planner.open_list.push(gold_sub, score)
# TODO speed up by remembering the features in planner
feats = self._extract_feats(gold_sub, gold.da)
gold_sub = Inst(tree=gold_sub, da=gold.da, feats=feats, score=0)
self._update_weights(gold_sub, gen)
# otherwise, update using the full gold tree
else:
self._update_weights(gold, gen)
return self.get_best_generated(gold)
def get_weights(self):
"""Return the current ranker weights (parameters). To be overridden by derived classes."""
raise NotImplementedError
def set_weights(self, w):
"""Set new ranker weights. To be overridden by derived classes."""
raise NotImplementedError
def set_weights_average(self, ws):
"""Set the weights as the average of the given array of weights (used in parallel training).
To be overridden by derived classes."""
raise NotImplementedError
def store_iter_weights(self):
"""Remember the current weights to be used for averaging.
To be overridden by derived classes."""
raise NotImplementedError
def set_weights_iter_average(self):
"""Set new weights as the average of all remembered weights. To be overridden by
derived classes."""
raise NotImplementedError
def get_weights_sum(self):
"""Return weights size in order to weigh future promise against them."""
raise NotImplementedError
def update_weights_sum(self):
"""Update the current weights size for future promise weighining."""
raise NotImplementedError
def reset_diagnostics(self):
"""Reset the evaluation statistics (Evaluator and ASearchListsAnalyzer objects)."""
self.evaluator = Evaluator()
self.lists_analyzer = ASearchListsAnalyzer()
def get_diagnostics(self):
"""Return the current evaluation statistics (a tuple of Evaluator and ASearchListsAnalyzer
objects."""
return self.evaluator, self.lists_analyzer
def set_diagnostics_average(self, diags):
"""Given an array of evaluation statistics objects, average them an store in this ranker
instance."""
self.reset_diagnostics()
for evaluator, lists_analyzer in diags:
self.evaluator.merge(evaluator)
self.lists_analyzer.merge(lists_analyzer)
def get_future_promise(self, cand_tree):
"""Compute expected future promise for a tree."""
w_sum = self.get_weights_sum()
if self.future_promise_type == 'num_nodes':
return w_sum * self.future_promise_weight * max(0, 10 - len(cand_tree))
elif self.future_promise_type == 'norm_exp_children':
return (self.candgen.get_future_promise(cand_tree) / len(cand_tree)) * w_sum * self.future_promise_weight
elif self.future_promise_type == 'ands':
prom = 0
for idx, node in enumerate(cand_tree.nodes):
if node.t_lemma == 'and':
num_kids = cand_tree.children_num(idx)
prom += max(0, 2 - num_kids)
return prom * w_sum * self.future_promise_weight
else: # expected children (default)
return self.candgen.get_future_promise(cand_tree) * w_sum * self.future_promise_weight
def get_future_promise_all(self, cand_trees):
"""Array version of get_future_promise."""
return [self.get_future_promise(cand_tree) for cand_tree in cand_trees]
def asearch_gen(args):
"""A*search generation"""
from pytreex.core.document import Document
opts, files = getopt(args, 'e:d:w:c:s:')
eval_file = None
fname_ttrees_out = None
cfg_file = None
eval_selector = ''
for opt, arg in opts:
if opt == '-e':
eval_file = arg
elif opt == '-s':
eval_selector = arg
elif opt == '-d':
set_debug_stream(file_stream(arg, mode='w'))
elif opt == '-w':
fname_ttrees_out = arg
elif opt == '-c':
cfg_file = arg
if len(files) != 3:
sys.exit('Invalid arguments.\n' + __doc__)
fname_cand_model, fname_rank_model, fname_da_test = files
log_info('Initializing...')
candgen = RandomCandidateGenerator.load_from_file(fname_cand_model)
ranker = PerceptronRanker.load_from_file(fname_rank_model)
cfg = Config(cfg_file) if cfg_file else {}
cfg.update({'candgen': candgen, 'ranker': ranker})
tgen = ASearchPlanner(cfg)
log_info('Generating...')
das = read_das(fname_da_test)
if eval_file is None:
gen_doc = Document()
else:
eval_doc = read_ttrees(eval_file)
if eval_selector == tgen.selector:
gen_doc = Document()
else:
gen_doc = eval_doc
# generate and evaluate
if eval_file is not None:
# generate + analyze open&close lists
lists_analyzer = ASearchListsAnalyzer()
for num, (da, gold_tree) in enumerate(zip(
das, trees_from_doc(eval_doc, tgen.language, eval_selector)),
start=1):
log_debug("\n\nTREE No. %03d" % num)
gen_tree = tgen.generate_tree(da, gen_doc)
lists_analyzer.append(gold_tree, tgen.open_list, tgen.close_list)
if gen_tree != gold_tree:
log_debug("\nDIFFING TREES:\n" +
tgen.ranker.diffing_trees_with_scores(
da, gold_tree, gen_tree) + "\n")
log_info('Gold tree BEST: %.4f, on CLOSE: %.4f, on ANY list: %4f' %
lists_analyzer.stats())
# evaluate the generated trees against golden trees
eval_ttrees = ttrees_from_doc(eval_doc, tgen.language, eval_selector)
gen_ttrees = ttrees_from_doc(gen_doc, tgen.language, tgen.selector)
log_info('Evaluating...')
evaler = Evaluator()
for eval_bundle, eval_ttree, gen_ttree, da in zip(
eval_doc.bundles, eval_ttrees, gen_ttrees, das):
# add some stats about the tree directly into the output file
add_bundle_text(
eval_bundle, tgen.language, tgen.selector + 'Xscore',
"P: %.4f R: %.4f F1: %.4f" %
p_r_f1_from_counts(*corr_pred_gold(eval_ttree, gen_ttree)))
# collect overall stats
evaler.append(eval_ttree, gen_ttree,
ranker.score(TreeData.from_ttree(eval_ttree), da),
ranker.score(TreeData.from_ttree(gen_ttree), da))
# print overall stats
log_info("NODE precision: %.4f, Recall: %.4f, F1: %.4f" %
evaler.p_r_f1())
log_info("DEP precision: %.4f, Recall: %.4f, F1: %.4f" %
evaler.p_r_f1(EvalTypes.DEP))
log_info("Tree size stats:\n * GOLD %s\n * PRED %s\n * DIFF %s" %
evaler.size_stats())
log_info("Score stats:\n * GOLD %s\n * PRED %s\n * DIFF %s" %
evaler.score_stats())
log_info(
"Common subtree stats:\n -- SIZE: %s\n -- ΔGLD: %s\n -- ΔPRD: %s" %
evaler.common_substruct_stats())
# just generate
else:
for da in das:
tgen.generate_tree(da, gen_doc)
# write output
if fname_ttrees_out is not None:
log_info('Writing output...')
write_ttrees(gen_doc, fname_ttrees_out)
def reset_diagnostics(self):
"""Reset the evaluation statistics (Evaluator and ASearchListsAnalyzer objects)."""
self.evaluator = Evaluator()
self.lists_analyzer = ASearchListsAnalyzer()
class BasePerceptronRanker(Ranker):
def __init__(self, cfg):
if not cfg:
cfg = {}
self.passes = cfg.get('passes', 5)
self.alpha = cfg.get('alpha', 1)
self.language = cfg.get('language', 'en')
self.selector = cfg.get('selector', '')
# initialize diagnostics
self.lists_analyzer = None
self.evaluator = None
self.prune_feats = cfg.get('prune_feats', 1)
self.rival_number = cfg.get('rival_number', 10)
self.averaging = cfg.get('averaging', False)
self.randomize = cfg.get('randomize', False)
self.future_promise_weight = cfg.get('future_promise_weight', 1.0)
self.future_promise_type = cfg.get('future_promise_type',
'expected_children')
self.rival_gen_strategy = cfg.get('rival_gen_strategy', ['other_inst'])
self.rival_gen_max_iter = cfg.get('rival_gen_max_iter', 50)
self.rival_gen_max_defic_iter = cfg.get('rival_gen_max_defic_iter', 3)
self.rival_gen_beam_size = cfg.get('rival_gen_beam_size')
self.rival_gen_prune_size = cfg.get('rival_gen_prune_size')
self.candgen_model = cfg.get('candgen_model')
self.diffing_trees = cfg.get('diffing_trees', False)
def score(self, cand_tree, da):
"""Score the given tree in the context of the given dialogue act.
@param cand_tree: the candidate tree to be scored, as a TreeData object
@param da: a DA object representing the input dialogue act
"""
return self._score(self._extract_feats(cand_tree, da))
def score_all(self, cand_trees, da):
"""Array version of the score() function"""
return [self.score(cand_tree, da) for cand_tree in cand_trees]
def _extract_feats(self, tree, da):
raise NotImplementedError
def train(self, das_file, ttree_file, data_portion=1.0):
"""Run training on the given training data."""
self._init_training(das_file, ttree_file, data_portion)
for iter_no in range(1, self.passes + 1):
self.train_order = list(range(len(self.train_trees)))
if self.randomize:
rnd.shuffle(self.train_order)
log_info("Train order: " + str(self.train_order))
self._training_pass(iter_no)
if self.evaluator.tree_accuracy(
) == 1: # if tree accuracy is 1, we won't learn anything anymore
break
# averaged perceptron – average the weights obtained after each pass
if self.averaging is True:
self.set_weights_iter_average()
def _init_training(self, das_file, ttree_file, data_portion):
"""Initialize training (read input data, fix size, initialize candidate generator
and planner)"""
# read input
log_info('Reading DAs from ' + das_file + '...')
das = read_das(das_file)
log_info('Reading t-trees from ' + ttree_file + '...')
ttree_doc = read_ttrees(ttree_file)
sents = sentences_from_doc(ttree_doc, self.language, self.selector)
trees = trees_from_doc(ttree_doc, self.language, self.selector)
# make training data smaller if necessary
train_size = int(round(data_portion * len(trees)))
self.train_trees = trees[:train_size]
self.train_das = das[:train_size]
self.train_sents = sents[:train_size]
self.train_order = list(range(len(self.train_trees)))
log_info('Using %d training instances.' % train_size)
# initialize candidate generator
if self.candgen_model is not None:
self.candgen = RandomCandidateGenerator.load_from_file(
self.candgen_model)
# self.sampling_planner = SamplingPlanner({'language': self.language,
# 'selector': self.selector,
# 'candgen': self.candgen})
# check if A*search planner is needed (i.e., any rival generation strategy requires it)
# and initialize it
if isinstance(self.rival_gen_strategy[0], tuple):
asearch_needed = any([
s in ['gen_cur_weights', 'gen_update']
for _, ss in self.rival_gen_strategy for s in ss
])
else:
asearch_needed = any([
s in ['gen_cur_weights', 'gen_update']
for s in self.rival_gen_strategy
])
if asearch_needed:
assert self.candgen is not None
self.asearch_planner = ASearchPlanner({
'candgen': self.candgen,
'language': self.language,
'selector': self.selector,
'ranker': self,
})
def _training_pass(self, pass_no):
"""Run one training pass, update weights (store them for possible averaging),
and store diagnostic values."""
pass_start_time = time.time()
self.reset_diagnostics()
self.update_weights_sum()
log_debug('\n***\nTR %05d:' % pass_no)
rgen_max_iter = self._get_num_iters(pass_no, self.rival_gen_max_iter)
rgen_max_defic_iter = self._get_num_iters(
pass_no, self.rival_gen_max_defic_iter)
rgen_beam_size = self.rival_gen_beam_size
rgen_prune_size = self.rival_gen_prune_size
rgen_strategy = self._get_rival_gen_strategy(pass_no)
for tree_no in self.train_order:
log_debug('TREE-NO: %d' % tree_no)
log_debug('SENT: %s' % self.train_sents[tree_no])
gold = Inst(da=self.train_das[tree_no],
tree=self.train_trees[tree_no],
score=self._score(self.train_feats[tree_no]),
feats=self.train_feats[tree_no])
# obtain some 'rival', alternative incorrect candidates
for strategy in rgen_strategy:
# generate using current weights
if strategy == 'gen_cur_weights':
gen = self._gen_cur_weights(gold, rgen_max_iter,
rgen_max_defic_iter,
rgen_prune_size,
rgen_beam_size)
# generate while trying to update weights
elif strategy == 'gen_update':
gen = self._gen_update(gold, rgen_max_iter,
rgen_max_defic_iter,
rgen_prune_size, rgen_beam_size)
# check against other possible candidates/combinations
else:
gen = self._get_rival_candidates(gold, tree_no, strategy)
# evaluate the top-scoring generated tree against gold t-tree
# (disregarding whether it was selected as the best one)
self.evaluator.append(TreeNode(gold.tree), TreeNode(gen.tree),
gold.score, gen.score)
# update weights if the system doesn't give the highest score to the gold standard tree
if gold.score < gen.score:
self._update_weights(gold, gen)
# store a copy of the current weights for averaging
self.store_iter_weights()
# debug print: current weights and pass accuracy
log_debug(self._feat_val_str(), '\n***')
log_debug('PASS ACCURACY: %.3f' % self.evaluator.tree_accuracy())
# print and return statistics
self._print_pass_stats(
pass_no,
datetime.timedelta(seconds=(time.time() - pass_start_time)))
def diffing_trees_with_scores(self, da, good_tree, bad_tree):
"""For debugging purposes. Return a printout of diffing trees between the chosen candidate
and the gold tree, along with scores."""
good_sts, bad_sts = good_tree.diffing_trees(bad_tree, symmetric=False)
comm_st = good_tree.get_common_subtree(bad_tree)
ret = 'Common subtree: %.3f' % self.score(
comm_st, da) + "\t" + str(comm_st) + "\n"
ret += "Good subtrees:\n"
for good_st in good_sts:
ret += "%.3f" % self.score(good_st,
da) + "\t" + str(good_st) + "\n"
ret += "Bad subtrees:\n"
for bad_st in bad_sts:
ret += "%.3f" % self.score(bad_st, da) + "\t" + str(bad_st) + "\n"
return ret
def _get_num_iters(self, cur_pass_no, iter_setting):
"""Return the maximum number of iterations (total/deficit) given the current pass.
Used to keep track of variable iteration number setting in configuration.
@param cur_pass_no: the number of the current pass
@param iter_setting: number of iteration setting (self.max_iter or self.max_defic_iter)
"""
if isinstance(iter_setting, (list, tuple)):
ret = 0
for set_pass_no, set_iter_no in iter_setting:
if set_pass_no > cur_pass_no:
break
ret = set_iter_no
return ret
else:
return iter_setting # a single setting for all passes
def _get_rival_gen_strategy(self, cur_pass_no):
"""Return the rival generation strategy/strategies for the current pass.
Used to keep track of variable rival generation setting setting in configuration.
@param cur_pass_no: the number of the current pass
"""
if isinstance(self.rival_gen_strategy[0], tuple):
ret = []
for set_pass_no, strategies in self.rival_gen_strategy:
if set_pass_no > cur_pass_no:
break
ret = strategies
return ret
else:
return self.rival_gen_strategy # a single setting for all passes
def _print_pass_stats(self, pass_no, pass_duration):
"""Print pass statistics from internal evaluator fields and given pass duration."""
log_info('Pass %05d -- tree-level accuracy: %.4f' %
(pass_no, self.evaluator.tree_accuracy()))
log_info(' * Generated trees NODE scores: P: %.4f, R: %.4f, F: %.4f' %
self.evaluator.p_r_f1())
log_info(' * Generated trees DEP scores: P: %.4f, R: %.4f, F: %.4f' %
self.evaluator.p_r_f1(EvalTypes.DEP))
log_info(' * Gold tree BEST: %.4f, on CLOSE: %.4f, on ANY list: %.4f' %
self.lists_analyzer.stats())
log_info(
' * Tree size stats:\n -- GOLD: %s\n -- PRED: %s\n -- DIFF: %s' %
self.evaluator.size_stats())
log_info(
' * Common subtree stats:\n -- SIZE: %s\n -- ΔGLD: %s\n -- ΔPRD: %s'
% self.evaluator.common_substruct_stats())
log_info(' * Score stats\n -- GOLD: %s\n -- PRED: %s\n -- DIFF: %s' %
self.evaluator.score_stats())
log_info(' * Duration: %s' % str(pass_duration))
def _feat_val_str(self, sep='\n', nonzero=False):
"""Return feature names and values for printing. To be overridden in base classes."""
return ''
def _get_rival_candidates(self, gold, tree_no, strategy):
"""Generate some rival candidates for a DA and the correct (gold) tree,
given a strategy; using other DAs for the correct tree, other trees for the correct
DA, or random trees.
NB: This has not been shown to be usable in practice; use _gen_cur_weights() instead.
TODO: checking for trees identical to the gold one slows down the process
@param tree_no: the index of the current training data item (tree, DA)
@rtype: tuple of two lists: one of TreeData's, one of arrays
@return: an array of rival trees and an array of the corresponding features
"""
train_trees = self.train_trees
rival_das, rival_trees, rival_feats = [], [], []
if strategy != 'other_da':
rival_das = [gold.da] * self.rival_number
# use current DA but change trees when computing features
if strategy == 'other_inst':
# use alternative indexes, avoid the correct one
rival_idxs = [
len(train_trees) - 1 if idx == tree_no else idx
for idx in rnd.sample(range(len(train_trees) -
1), self.rival_number)
]
other_inst_trees = [
train_trees[rival_idx] for rival_idx in rival_idxs
]
rival_trees.extend(other_inst_trees)
rival_feats.extend([
self._extract_feats(tree, gold.da) for tree in other_inst_trees
])
# use the current gold tree but change DAs when computing features
if strategy == 'other_da':
rival_idxs = [
len(train_trees) - 1 if idx == tree_no else idx
for idx in rnd.sample(range(len(train_trees) -
1), self.rival_number)
]
other_inst_das = [
self.train_das[rival_idx] for rival_idx in rival_idxs
]
rival_das.extend(other_inst_das)
rival_trees.extend([self.train_trees[tree_no]] * self.rival_number)
rival_feats.extend([
self._extract_feats(self.train_trees[tree_no], da)
for da in other_inst_das
])
# # candidates generated using the random planner (use the current DA)
# if strategy == 'random':
# random_trees = []
# while len(random_trees) < self.rival_number:
# tree = self.sampling_planner.generate_tree(da)
# if (tree != train_trees[tree_no]): # don't generate trees identical to the gold one
# random_trees.append(tree)
# rival_trees.extend(random_trees)
# rival_feats.extend([self._extract_feats(tree, da) for tree in random_trees])
# score them along with the right one
rival_scores = [self._score(r) for r in rival_feats]
top_rival_idx = rival_scores.index(max(rival_scores))
gen = Inst(tree=rival_trees[top_rival_idx],
da=rival_das[top_rival_idx],
score=rival_scores[top_rival_idx],
feats=rival_feats[top_rival_idx])
# debug print: candidate trees
log_debug('#RIVALS: %02d' % len(rival_feats))
log_debug('SEL: GOLD' if gold.score >= gen.score else (
'SEL: RIVAL#%d' % top_rival_idx))
log_debug('ALL CAND TREES:')
for ttree, score in zip([gold.tree] + rival_trees,
[gold.score] + rival_scores):
log_debug("%12.5f" % score, "\t", ttree)
return gen
def _gen_cur_weights(self, gold, max_iter, max_defic_iter, prune_size,
beam_size):
"""
Get the best candidate generated using the A*search planner, which uses this ranker with current
weights to guide the search, and the current DA as the input.
@param gold: the gold-standard Inst holding the input DA for generation and the reference tree
@param max_iter: maximum number of A*-search iterations to run
@param max_defic_iter: maximum number of deficit A*-search iterations (stopping criterion)
@param prune_size: beam size for open list pruning
@param beam_size: beam size for candidate expansion (expand more per iteration if > 1)
@return: The best generated tree that is different from the gold-standard tree
@rtype: Inst
"""
log_debug('GEN-CUR-WEIGHTS')
# TODO make asearch_planner remember features (for last iteration, maybe)
self.asearch_planner.run(gold.da, max_iter, max_defic_iter, prune_size,
beam_size)
return self.get_best_generated(gold)
def get_best_generated(self, gold):
"""Return the best generated tree that is different from the gold-standard tree
(to be used for updates, if it scores better). Also, keep track of logging and
update analyzer lists.
@param gold: the gold-standard Inst from which the generated tree must differ
@rtype: Inst
"""
self.lists_analyzer.append(gold.tree, self.asearch_planner.open_list,
self.asearch_planner.close_list)
gen_tree = gold.tree
while self.asearch_planner.close_list and gen_tree == gold.tree:
gen_tree, gen_score = self.asearch_planner.close_list.pop()
# scores are negative on the close list – reverse the sign
gen = Inst(tree=gen_tree,
da=gold.da,
score=-gen_score,
feats=self._extract_feats(gen_tree, gold.da))
log_debug('SEL: GOLD' if gold.score >= gen.score else 'SEL: GEN')
log_debug("GOLD:\t", "%12.5f" % gold.score, "\t", gold.tree)
log_debug("GEN :\t", "%12.5f" % gen.score, "\t", gen.tree)
return gen
def _gen_update(self, gold, max_iter, max_defic_iter, prune_size,
beam_size):
"""Try generating using the current weights, but update the weights after each
iteration if the result is not going in the right direction (not a subtree of the
gold-standard tree).
@param gold: the gold-standard Inst holding the input DA for generation and the reference tree
@param max_iter: maximum number of A*-search iterations to run
@param max_defic_iter: maximum number of deficit A*-search iterations (stopping criterion)
@param prune_size: beam size for open list pruning
@param beam_size: beam size for candidate expansion (expand more per iteration if > 1)
@return: The best generated tree that is different from the gold-standard tree
@rtype: Inst
"""
log_debug('GEN-UPDATE')
self.asearch_planner.init_run(gold.da, max_iter, max_defic_iter,
prune_size, beam_size)
while not self.asearch_planner.check_finalize():
# run one A*search iteration
self.asearch_planner.run_iter()
# stop if there's nothing on the open list
if not self.asearch_planner.open_list:
break
# look if we are on the right track to the gold tree
cur_top, score = self.asearch_planner.open_list.peek()
csi, _ = gold.tree.common_subtree_idxs(cur_top)
# if not, update
if len(csi) != len(cur_top):
feats = self._extract_feats(cur_top, gold.da)
gen = Inst(tree=cur_top, da=gold.da, feats=feats, score=score)
# for small wrong trees,
# fake the current open list to only include a subtree of the gold tree
# TODO fake it better, include more variants
# update using a subtree of the gold tree
if len(cur_top) < len(gold.tree):
diff = sorted(list(set(range(len(gold.tree))) - set(csi)),
cmp=gold.tree._compare_node_depth)
gold_sub = gold.tree.get_subtree(csi +
diff[0:len(cur_top) -
len(gold.tree)])
self.asearch_planner.open_list.clear()
self.asearch_planner.open_list.push(gold_sub, score)
# TODO speed up by remembering the features in planner
feats = self._extract_feats(gold_sub, gold.da)
gold_sub = Inst(tree=gold_sub,
da=gold.da,
feats=feats,
score=0)
self._update_weights(gold_sub, gen)
# otherwise, update using the full gold tree
else:
self._update_weights(gold, gen)
return self.get_best_generated(gold)
def get_weights(self):
"""Return the current ranker weights (parameters). To be overridden by derived classes."""
raise NotImplementedError
def set_weights(self, w):
"""Set new ranker weights. To be overridden by derived classes."""
raise NotImplementedError
def set_weights_average(self, ws):
"""Set the weights as the average of the given array of weights (used in parallel training).
To be overridden by derived classes."""
raise NotImplementedError
def store_iter_weights(self):
"""Remember the current weights to be used for averaging.
To be overridden by derived classes."""
raise NotImplementedError
def set_weights_iter_average(self):
"""Set new weights as the average of all remembered weights. To be overridden by
derived classes."""
raise NotImplementedError
def get_weights_sum(self):
"""Return weights size in order to weigh future promise against them."""
raise NotImplementedError
def update_weights_sum(self):
"""Update the current weights size for future promise weighining."""
raise NotImplementedError
def reset_diagnostics(self):
"""Reset the evaluation statistics (Evaluator and ASearchListsAnalyzer objects)."""
self.evaluator = Evaluator()
self.lists_analyzer = ASearchListsAnalyzer()
def get_diagnostics(self):
"""Return the current evaluation statistics (a tuple of Evaluator and ASearchListsAnalyzer
objects."""
return self.evaluator, self.lists_analyzer
def set_diagnostics_average(self, diags):
"""Given an array of evaluation statistics objects, average them an store in this ranker
instance."""
self.reset_diagnostics()
for evaluator, lists_analyzer in diags:
self.evaluator.merge(evaluator)
self.lists_analyzer.merge(lists_analyzer)
def get_future_promise(self, cand_tree):
"""Compute expected future promise for a tree."""
w_sum = self.get_weights_sum()
if self.future_promise_type == 'num_nodes':
return w_sum * self.future_promise_weight * max(
0, 10 - len(cand_tree))
elif self.future_promise_type == 'norm_exp_children':
return (old_div(
self.candgen.get_future_promise(cand_tree),
len(cand_tree))) * w_sum * self.future_promise_weight
elif self.future_promise_type == 'ands':
prom = 0
for idx, node in enumerate(cand_tree.nodes):
if node.t_lemma == 'and':
num_kids = cand_tree.children_num(idx)
prom += max(0, 2 - num_kids)
return prom * w_sum * self.future_promise_weight
else: # expected children (default)
return self.candgen.get_future_promise(
cand_tree) * w_sum * self.future_promise_weight
def get_future_promise_all(self, cand_trees):
"""Array version of get_future_promise."""
return [self.get_future_promise(cand_tree) for cand_tree in cand_trees]
def reset_diagnostics(self):
"""Reset the evaluation statistics (Evaluator and ASearchListsAnalyzer objects)."""
self.evaluator = Evaluator()
self.lists_analyzer = ASearchListsAnalyzer()
def asearch_gen(args):
"""A*search generation"""
from pytreex.core.document import Document
opts, files = getopt(args, 'e:d:w:c:s:')
eval_file = None
fname_ttrees_out = None
cfg_file = None
eval_selector = ''
for opt, arg in opts:
if opt == '-e':
eval_file = arg
elif opt == '-s':
eval_selector = arg
elif opt == '-d':
set_debug_stream(file_stream(arg, mode='w'))
elif opt == '-w':
fname_ttrees_out = arg
elif opt == '-c':
cfg_file = arg
if len(files) != 3:
sys.exit('Invalid arguments.\n' + __doc__)
fname_cand_model, fname_rank_model, fname_da_test = files
log_info('Initializing...')
candgen = RandomCandidateGenerator.load_from_file(fname_cand_model)
ranker = PerceptronRanker.load_from_file(fname_rank_model)
cfg = Config(cfg_file) if cfg_file else {}
cfg.update({'candgen': candgen, 'ranker': ranker})
tgen = ASearchPlanner(cfg)
log_info('Generating...')
das = read_das(fname_da_test)
if eval_file is None:
gen_doc = Document()
else:
eval_doc = read_ttrees(eval_file)
if eval_selector == tgen.selector:
gen_doc = Document()
else:
gen_doc = eval_doc
# generate and evaluate
if eval_file is not None:
# generate + analyze open&close lists
lists_analyzer = ASearchListsAnalyzer()
for num, (da, gold_tree) in enumerate(zip(das,
trees_from_doc(eval_doc, tgen.language, eval_selector)),
start=1):
log_debug("\n\nTREE No. %03d" % num)
gen_tree = tgen.generate_tree(da, gen_doc)
lists_analyzer.append(gold_tree, tgen.open_list, tgen.close_list)
if gen_tree != gold_tree:
log_debug("\nDIFFING TREES:\n" + tgen.ranker.diffing_trees_with_scores(da, gold_tree, gen_tree) + "\n")
log_info('Gold tree BEST: %.4f, on CLOSE: %.4f, on ANY list: %4f' % lists_analyzer.stats())
# evaluate the generated trees against golden trees
eval_ttrees = ttrees_from_doc(eval_doc, tgen.language, eval_selector)
gen_ttrees = ttrees_from_doc(gen_doc, tgen.language, tgen.selector)
log_info('Evaluating...')
evaler = Evaluator()
for eval_bundle, eval_ttree, gen_ttree, da in zip(eval_doc.bundles, eval_ttrees, gen_ttrees, das):
# add some stats about the tree directly into the output file
add_bundle_text(eval_bundle, tgen.language, tgen.selector + 'Xscore',
"P: %.4f R: %.4f F1: %.4f" % p_r_f1_from_counts(*corr_pred_gold(eval_ttree, gen_ttree)))
# collect overall stats
evaler.append(eval_ttree,
gen_ttree,
ranker.score(TreeData.from_ttree(eval_ttree), da),
ranker.score(TreeData.from_ttree(gen_ttree), da))
# print overall stats
log_info("NODE precision: %.4f, Recall: %.4f, F1: %.4f" % evaler.p_r_f1())
log_info("DEP precision: %.4f, Recall: %.4f, F1: %.4f" % evaler.p_r_f1(EvalTypes.DEP))
log_info("Tree size stats:\n * GOLD %s\n * PRED %s\n * DIFF %s" % evaler.size_stats())
log_info("Score stats:\n * GOLD %s\n * PRED %s\n * DIFF %s" % evaler.score_stats())
log_info("Common subtree stats:\n -- SIZE: %s\n -- ΔGLD: %s\n -- ΔPRD: %s" %
evaler.common_substruct_stats())
# just generate
else:
for da in das:
tgen.generate_tree(da, gen_doc)
# write output
if fname_ttrees_out is not None:
log_info('Writing output...')
write_ttrees(gen_doc, fname_ttrees_out)
class BasePerceptronRanker(Ranker):
def __init__(self, cfg):
if not cfg:
cfg = {}
self.passes = cfg.get('passes', 5)
self.alpha = cfg.get('alpha', 1)
self.language = cfg.get('language', 'en')
self.selector = cfg.get('selector', '')
# initialize diagnostics
self.lists_analyzer = None
self.evaluator = None
self.prune_feats = cfg.get('prune_feats', 1)
self.rival_number = cfg.get('rival_number', 10)
self.averaging = cfg.get('averaging', False)
self.randomize = cfg.get('randomize', False)
self.future_promise_weight = cfg.get('future_promise_weight', 1.0)
self.future_promise_type = cfg.get('future_promise_type', 'expected_children')
self.rival_gen_strategy = cfg.get('rival_gen_strategy', ['other_inst'])
self.rival_gen_max_iter = cfg.get('rival_gen_max_iter', 50)
self.rival_gen_max_defic_iter = cfg.get('rival_gen_max_defic_iter', 3)
self.rival_gen_beam_size = cfg.get('rival_gen_beam_size')
self.candgen_model = cfg.get('candgen_model')
self.diffing_trees = cfg.get('diffing_trees', False)
def score(self, cand_tree, da):
"""Score the given tree in the context of the given dialogue act.
@param cand_tree: the candidate tree to be scored, as a TreeData object
@param da: a DialogueAct object representing the input dialogue act
"""
return self._score(self._extract_feats(cand_tree, da))
def score_all(self, cand_trees, da):
"""Array version of the score() function"""
return [self.score(cand_tree, da) for cand_tree in cand_trees]
def _extract_feats(self, tree, da):
raise NotImplementedError
def train(self, das_file, ttree_file, data_portion=1.0):
"""Run training on the given training data."""
self._init_training(das_file, ttree_file, data_portion)
for iter_no in xrange(1, self.passes + 1):
self.train_order = range(len(self.train_trees))
if self.randomize:
rnd.shuffle(self.train_order)
log_info("Train order: " + str(self.train_order))
self._training_pass(iter_no)
if self.evaluator.tree_accuracy() == 1: # if tree accuracy is 1, we won't learn anything anymore
break
# averaged perceptron – average the weights obtained after each pass
if self.averaging is True:
self.set_weights_iter_average()
def _init_training(self, das_file, ttree_file, data_portion):
"""Initialize training (read input data, fix size, initialize candidate generator
and planner)"""
# read input
log_info('Reading DAs from ' + das_file + '...')
das = read_das(das_file)
log_info('Reading t-trees from ' + ttree_file + '...')
ttree_doc = read_ttrees(ttree_file)
sents = sentences_from_doc(ttree_doc, self.language, self.selector)
trees = trees_from_doc(ttree_doc, self.language, self.selector)
# make training data smaller if necessary
train_size = int(round(data_portion * len(trees)))
self.train_trees = trees[:train_size]
self.train_das = das[:train_size]
self.train_sents = sents[:train_size]
self.train_order = range(len(self.train_trees))
log_info('Using %d training instances.' % train_size)
# initialize candidate generator + planner if needed
if self.candgen_model is not None:
self.candgen = RandomCandidateGenerator.load_from_file(self.candgen_model)
self.sampling_planner = SamplingPlanner({'language': self.language,
'selector': self.selector,
'candgen': self.candgen})
if 'gen_cur_weights' in self.rival_gen_strategy:
assert self.candgen is not None
self.asearch_planner = ASearchPlanner({'candgen': self.candgen,
'language': self.language,
'selector': self.selector,
'ranker': self, })
def _training_pass(self, pass_no):
"""Run one training pass, update weights (store them for possible averaging),
and store diagnostic values."""
pass_start_time = time.time()
self.reset_diagnostics()
self.update_weights_sum()
log_debug('\n***\nTR %05d:' % pass_no)
rgen_max_iter = self._get_num_iters(pass_no, self.rival_gen_max_iter)
rgen_max_defic_iter = self._get_num_iters(pass_no, self.rival_gen_max_defic_iter)
rgen_beam_size = self.rival_gen_beam_size
for tree_no in self.train_order:
# obtain some 'rival', alternative incorrect candidates
gold_da, gold_tree, gold_feats = self.train_das[tree_no], self.train_trees[tree_no], self.train_feats[tree_no]
for strategy in self.rival_gen_strategy:
rival_das, rival_trees, rival_feats = self._get_rival_candidates(tree_no, strategy, rgen_max_iter,
rgen_max_defic_iter, rgen_beam_size)
cands = [gold_feats] + rival_feats
# score them along with the right one
scores = [self._score(cand) for cand in cands]
top_cand_idx = scores.index(max(scores))
top_rival_idx = scores[1:].index(max(scores[1:]))
top_rival_tree = rival_trees[top_rival_idx]
top_rival_da = rival_das[top_rival_idx]
# find the top-scoring generated tree, evaluate against gold t-tree
# (disregarding whether it was selected as the best one)
self.evaluator.append(TreeNode(gold_tree), TreeNode(top_rival_tree), scores[0], max(scores[1:]))
# debug print: candidate trees
log_debug('TTREE-NO: %04d, SEL_CAND: %04d, LEN: %02d' % (tree_no, top_cand_idx, len(cands)))
log_debug('SENT: %s' % self.train_sents[tree_no])
log_debug('ALL CAND TREES:')
for ttree, score in zip([gold_tree] + rival_trees, scores):
log_debug("%12.5f" % score, "\t", ttree)
# update weights if the system doesn't give the highest score to the right one
if top_cand_idx != 0:
self._update_weights(gold_da, top_rival_da, gold_tree, top_rival_tree,
gold_feats, cands[top_cand_idx])
# store a copy of the current weights for averaging
self.store_iter_weights()
# debug print: current weights and pass accuracy
log_debug(self._feat_val_str(), '\n***')
log_debug('PASS ACCURACY: %.3f' % self.evaluator.tree_accuracy())
# print and return statistics
self._print_pass_stats(pass_no, datetime.timedelta(seconds=(time.time() - pass_start_time)))
def diffing_trees_with_scores(self, da, good_tree, bad_tree):
"""For debugging purposes. Return a printout of diffing trees between the chosen candidate
and the gold tree, along with scores."""
good_sts, bad_sts = good_tree.diffing_trees(bad_tree, symmetric=False)
comm_st = good_tree.get_common_subtree(bad_tree)
ret = 'Common subtree: %.3f' % self.score(comm_st, da) + "\t" + unicode(comm_st) + "\n"
ret += "Good subtrees:\n"
for good_st in good_sts:
ret += "%.3f" % self.score(good_st, da) + "\t" + unicode(good_st) + "\n"
ret += "Bad subtrees:\n"
for bad_st in bad_sts:
ret += "%.3f" % self.score(bad_st, da) + "\t" + unicode(bad_st) + "\n"
return ret
def _get_num_iters(self, cur_pass_no, iter_setting):
"""Return the maximum number of iterations (total/deficit) given the current pass.
Used to keep track of variable iteration number setting in configuration."""
if isinstance(iter_setting, (list, tuple)):
ret = 0
for set_pass_no, set_iter_no in iter_setting:
if set_pass_no > cur_pass_no:
break
ret = set_iter_no
return ret
else:
return iter_setting # a single setting for all passes
def _print_pass_stats(self, pass_no, pass_duration):
"""Print pass statistics from internal evaluator fields and given pass duration."""
log_info('Pass %05d -- tree-level accuracy: %.4f' % (pass_no, self.evaluator.tree_accuracy()))
log_info(' * Generated trees NODE scores: P: %.4f, R: %.4f, F: %.4f' %
self.evaluator.p_r_f1())
log_info(' * Generated trees DEP scores: P: %.4f, R: %.4f, F: %.4f' %
self.evaluator.p_r_f1(EvalTypes.DEP))
log_info(' * Gold tree BEST: %.4f, on CLOSE: %.4f, on ANY list: %.4f' %
self.lists_analyzer.stats())
log_info(' * Tree size stats:\n -- GOLD: %s\n -- PRED: %s\n -- DIFF: %s' %
self.evaluator.tree_size_stats())
log_info(' * Common subtree stats:\n -- SIZE: %s\n -- ΔGLD: %s\n -- ΔPRD: %s' %
self.evaluator.common_subtree_stats())
log_info(' * Score stats\n -- GOLD: %s\n -- PRED: %s\n -- DIFF: %s'
% self.evaluator.score_stats())
log_info(' * Duration: %s' % str(pass_duration))
def _feat_val_str(self, sep='\n', nonzero=False):
"""Return feature names and values for printing. To be overridden in base classes."""
return ''
def _get_rival_candidates(self, tree_no, strategy, max_iter, max_defic_iter, beam_size):
"""Generate some rival candidates for a DA and the correct (gold) tree,
given the current rival generation strategy (self.rival_gen_strategy).
TODO: checking for trees identical to the gold one slows down the process
TODO: remove other generation strategies, remove support for multiple generated trees
@param tree_no: the index of the current training data item (tree, DA)
@rtype: tuple of two lists: one of TreeData's, one of arrays
@return: an array of rival trees and an array of the corresponding features
"""
da = self.train_das[tree_no]
train_trees = self.train_trees
rival_das, rival_trees, rival_feats = [], [], []
if strategy != 'other_da':
rival_das = [da] * self.rival_number
# use current DA but change trees when computing features
if strategy == 'other_inst':
# use alternative indexes, avoid the correct one
rival_idxs = map(lambda idx: len(train_trees) - 1 if idx == tree_no else idx,
rnd.sample(xrange(len(train_trees) - 1), self.rival_number))
other_inst_trees = [train_trees[rival_idx] for rival_idx in rival_idxs]
rival_trees.extend(other_inst_trees)
rival_feats.extend([self._extract_feats(tree, da) for tree in other_inst_trees])
# use the current gold tree but change DAs when computing features
if strategy == 'other_da':
rival_idxs = map(lambda idx: len(train_trees) - 1 if idx == tree_no else idx,
rnd.sample(xrange(len(train_trees) - 1), self.rival_number))
other_inst_das = [self.train_das[rival_idx] for rival_idx in rival_idxs]
rival_das.extend(other_inst_das)
rival_trees.extend([self.train_trees[tree_no]] * self.rival_number)
rival_feats.extend([self._extract_feats(self.train_trees[tree_no], da)
for da in other_inst_das])
# candidates generated using the random planner (use the current DA)
if strategy == 'random':
random_trees = []
while len(random_trees) < self.rival_number:
tree = self.sampling_planner.generate_tree(da)
if (tree != train_trees[tree_no]): # don't generate trees identical to the gold one
random_trees.append(tree)
rival_trees.extend(random_trees)
rival_feats.extend([self._extract_feats(tree, da) for tree in random_trees])
# candidates generated using the A*search planner, which uses this ranker with current
# weights to guide the search, and the current DA as the input
# TODO: use just one!, others are meaningless
if strategy == 'gen_cur_weights':
open_list, close_list = self.asearch_planner.run(da, max_iter, max_defic_iter, beam_size)
self.lists_analyzer.append(train_trees[tree_no], open_list, close_list)
gen_trees = []
while close_list and len(gen_trees) < self.rival_number:
tree = close_list.pop()[0]
if tree != train_trees[tree_no]:
gen_trees.append(tree)
rival_trees.extend(gen_trees[:self.rival_number])
rival_feats.extend([self._extract_feats(tree, da)
for tree in gen_trees[:self.rival_number]])
# return all resulting candidates
return rival_das, rival_trees, rival_feats
def get_weights(self):
"""Return the current ranker weights (parameters). To be overridden by derived classes."""
raise NotImplementedError
def set_weights(self, w):
"""Set new ranker weights. To be overridden by derived classes."""
raise NotImplementedError
def set_weights_average(self, ws):
"""Set the weights as the average of the given array of weights (used in parallel training).
To be overridden by derived classes."""
raise NotImplementedError
def store_iter_weights(self):
"""Remember the current weights to be used for averaging.
To be overridden by derived classes."""
raise NotImplementedError
def set_weights_iter_average(self):
"""Set new weights as the average of all remembered weights. To be overridden by
derived classes."""
raise NotImplementedError
def get_weights_sum(self):
"""Return weights size in order to weigh future promise against them."""
raise NotImplementedError
def update_weights_sum(self):
"""Update the current weights size for future promise weighining."""
raise NotImplementedError
def reset_diagnostics(self):
"""Reset the evaluation statistics (Evaluator and ASearchListsAnalyzer objects)."""
self.evaluator = Evaluator()
self.lists_analyzer = ASearchListsAnalyzer()
def get_diagnostics(self):
"""Return the current evaluation statistics (a tuple of Evaluator and ASearchListsAnalyzer
objects."""
return self.evaluator, self.lists_analyzer
def set_diagnostics_average(self, diags):
"""Given an array of evaluation statistics objects, average them an store in this ranker
instance."""
self.reset_diagnostics()
for evaluator, lists_analyzer in diags:
self.evaluator.merge(evaluator)
self.lists_analyzer.merge(lists_analyzer)
def get_future_promise(self, cand_tree):
"""Compute expected future promise for a tree."""
w_sum = self.get_weights_sum()
if self.future_promise_type == 'num_nodes':
return w_sum * self.future_promise_weight * max(0, 10 - len(cand_tree))
elif self.future_promise_type == 'norm_exp_children':
return (self.candgen.get_future_promise(cand_tree) / len(cand_tree)) * w_sum * self.future_promise_weight
elif self.future_promise_type == 'ands':
prom = 0
for idx, node in enumerate(cand_tree.nodes):
if node.t_lemma == 'and':
num_kids = cand_tree.children_num(idx)
prom += max(0, 2 - num_kids)
return prom * w_sum * self.future_promise_weight
else: # expected children (default)
return self.candgen.get_future_promise(cand_tree) * w_sum * self.future_promise_weight
def get_future_promise_all(self, cand_trees):
"""Array version of get_future_promise."""
return [self.get_future_promise(cand_tree) for cand_tree in cand_trees]