def extract_bias_features(text):
features = {}
text = unicode(text,
errors='ignore') if not isinstance(text, unicode) else text
txt_lwr = str(text).lower()
words = nltk.word_tokenize(txt_lwr)
words = [w for w in words if len(w) > 0 and w not in '.?!,;:\'s"$']
unigrams = sorted(list(set(words)))
bigram_tokens = nltk.bigrams(words)
bigrams = [" ".join([w1, w2]) for w1, w2 in sorted(set(bigram_tokens))]
trigram_tokens = nltk.trigrams(words)
trigrams = [
" ".join([w1, w2, w3]) for w1, w2, w3 in sorted(set(trigram_tokens))
]
# word count
features['word_cnt'] = len(words)
# unique word count
features['unique_word_cnt'] = len(unigrams)
# coherence marker count
count = count_feature_list_freq(coherence, words, bigrams, trigrams)
features['cm_cnt'] = count
features['cm_rto'] = round(float(count) / float(len(words)), 4)
# degree modifier count
count = count_feature_list_freq(modifiers, words, bigrams, trigrams)
features['dm_cnt'] = count
features['dm_rto'] = round(float(count) / float(len(words)), 4)
# hedge word count
count = count_feature_list_freq(hedges, words, bigrams, trigrams)
features['hedge_cnt'] = count
features['hedge_rto'] = round(float(count) / float(len(words)), 4)
# factive verb count
count = count_feature_list_freq(factives, words, bigrams, trigrams)
features['factive_cnt'] = count
features['factive_rto'] = round(float(count) / float(len(words)), 4)
# assertive verb count
count = count_feature_list_freq(assertives, words, bigrams, trigrams)
features['assertive_cnt'] = count
features['assertive_rto'] = round(float(count) / float(len(words)), 4)
# implicative verb count
count = count_feature_list_freq(implicatives, words, bigrams, trigrams)
features['implicative_cnt'] = count
features['implicative_rto'] = round(float(count) / float(len(words)), 4)
# bias words and phrases count
count = count_feature_list_freq(biased, words, bigrams, trigrams)
features['bias_cnt'] = count
features['bias_rto'] = round(float(count) / float(len(words)), 4)
# opinion word count
count = count_feature_list_freq(opinionLaden, words, bigrams, trigrams)
features['opinion_cnt'] = count
features['opinion_rto'] = round(float(count) / float(len(words)), 4)
# weak subjective word count
count = count_feature_list_freq(subj_weak, words, bigrams, trigrams)
features['subj_weak_cnt'] = count
features['subj_weak_rto'] = round(float(count) / float(len(words)), 4)
# strong subjective word count
count = count_feature_list_freq(subj_strong, words, bigrams, trigrams)
features['subj_strong_cnt'] = count
features['subj_strong_rto'] = round(float(count) / float(len(words)), 4)
# composite sentiment score using VADER sentiment analysis package
compound_sentiment = vader_sentiment_analysis.polarity_scores(
text)['compound']
features['vader_sentiment'] = compound_sentiment
# subjectivity score using Pattern.en
pattern_subjectivity = pattern_sentiment(text)[1]
features['subjectivity'] = round(pattern_subjectivity, 4)
# modality (certainty) score and mood using http://www.clips.ua.ac.be/pages/pattern-en#modality
sentence = parse(text, lemmata=True)
sentence_obj = Sentence(sentence)
features['modality'] = round(modality(sentence_obj), 4)
features['mood'] = mood(sentence_obj)
# Flesch-Kincaid Grade Level (reading difficulty) using textstat
features['fk_gl'] = textstat.flesch_kincaid_grade(text)
# liwc 3rd person pronoun count (combines S/he and They)
count = count_liwc_list_freq(liwc_3pp, words)
features['liwc_3pp_cnt'] = count
features['liwc_3pp_rto'] = round(float(count) / float(len(words)), 4)
# liwc auxiliary verb count
count = count_liwc_list_freq(liwc_aux, words)
features['liwc_aux_cnt'] = count
features['liwc_aux_rto'] = round(float(count) / float(len(words)), 4)
# liwc adverb count
count = count_liwc_list_freq(liwc_adv, words)
features['liwc_adv_cnt'] = count
features['liwc_adv_rto'] = round(float(count) / float(len(words)), 4)
# liwc preposition count
count = count_liwc_list_freq(liwc_prep, words)
features['liwc_prep_cnt'] = count
features['liwc_prep_rto'] = round(float(count) / float(len(words)), 4)
# liwc conjunction count
count = count_liwc_list_freq(liwc_conj, words)
features['liwc_conj_cnt'] = count
features['liwc_conj_rto'] = round(float(count) / float(len(words)), 4)
# liwc discrepency word count
count = count_liwc_list_freq(liwc_discr, words)
features['liwc_discr_cnt'] = count
features['liwc_discr_rto'] = round(float(count) / float(len(words)), 4)
# liwc tentative word count
count = count_liwc_list_freq(liwc_tent, words)
features['liwc_tent_cnt'] = count
features['liwc_tent_rto'] = round(float(count) / float(len(words)), 4)
# liwc certainty word count
count = count_liwc_list_freq(liwc_cert, words)
features['liwc_cert_cnt'] = count
features['liwc_cert_rto'] = round(float(count) / float(len(words)), 4)
# liwc causation word count
count = count_liwc_list_freq(liwc_causn, words)
features['liwc_causn_cnt'] = count
features['liwc_causn_rto'] = round(float(count) / float(len(words)), 4)
# liwc work word count
count = count_liwc_list_freq(liwc_work, words)
features['liwc_work_cnt'] = count
features['liwc_work_rto'] = round(float(count) / float(len(words)), 4)
# liwc achievement word count
count = count_liwc_list_freq(liwc_achiev, words)
features['liwc_achiev_cnt'] = count
features['liwc_achiev_rto'] = round(float(count) / float(len(words)), 4)
return features
def extract_bias_features(text, do_get_caster=False):
features = OrderedDict()
if sys.version_info < (3, 0):
# ignore conversion errors between utf-8 and ascii
text = text.decode('ascii', 'ignore')
text_nohyph = text.replace(
"-", " ") # preserve hyphenated words as separate tokens
txt_lwr = str(text_nohyph).lower()
words = ''.join(ch for ch in txt_lwr
if ch not in '!"#$%&()*+,-./:;<=>?@[\]^_`{|}~').split()
unigrams = sorted(list(set(words)))
bigram_tokens = find_ngrams(words, 2)
bigrams = [" ".join([w1, w2]) for w1, w2 in sorted(set(bigram_tokens))]
trigram_tokens = find_ngrams(words, 3)
trigrams = [
" ".join([w1, w2, w3]) for w1, w2, w3 in sorted(set(trigram_tokens))
]
## SENTENCE LEVEL MEASURES
# word count
features['word_cnt'] = len(words)
# unique word count
features['unique_word_cnt'] = len(unigrams)
# Flesch-Kincaid Grade Level (reading difficulty) using textstat
features['fk_gl'] = flesch_kincaid_grade(text)
# compound sentiment score using VADER sentiment analysis package
vader_sentiment = vader_sentiment_analysis.polarity_scores(text)
vader_negative_proportion = vader_sentiment['neg']
vader_compound_sentiment = vader_sentiment['compound']
features['vader_sentiment'] = vader_compound_sentiment
features['vader_senti_abs'] = abs(vader_compound_sentiment)
# negative-perspective
features['neg_persp'] = check_neg_persp(words, vader_negative_proportion,
vader_compound_sentiment)
# modality (certainty) score and mood using http://www.clips.ua.ac.be/pages/pattern-en#modality
sentence = parse(text, lemmata=True)
sentence_obj = Sentence(sentence)
features['certainty'] = round(modality(sentence_obj), 4)
# quoted material
quote_dict = check_quotes(text)
features["has_quotes"] = quote_dict["has_quotes"]
features["quote_length"] = quote_dict["mean_quote_length"]
features["nonquote_length"] = quote_dict["mean_nonquote_length"]
## LEXICON LEVEL MEASURES
# presupposition markers
count = count_feature_freq(presup, words, txt_lwr)
features['presup_cnt'] = count
features['presup_rto'] = round(old_div(float(count), float(len(words))), 4)
# doubt markers
count = count_feature_freq(doubt, words, txt_lwr)
features['doubt_cnt'] = count
features['doubt_rto'] = round(old_div(float(count), float(len(words))), 4)
# partisan words and phrases
count = count_feature_freq(partisan, words, txt_lwr)
features['partisan_cnt'] = count
features['partisan_rto'] = round(old_div(float(count), float(len(words))),
4)
# subjective value laden word count
count = count_feature_freq(value_laden, words, txt_lwr)
features['value_cnt'] = count
features['value_rto'] = round(old_div(float(count), float(len(words))), 4)
# figurative language markers
count = count_feature_freq(figurative, words, txt_lwr)
features['figurative_cnt'] = count
features['figurative_rto'] = round(
old_div(float(count), float(len(words))), 4)
# attribution markers
count = count_feature_freq(attribution, words, txt_lwr)
features['attribution_cnt'] = count
features['attribution_rto'] = round(
old_div(float(count), float(len(words))), 4)
# self reference pronouns
count = count_feature_freq(self_refer, words, txt_lwr)
features['self_refer_cnt'] = count
features['self_refer_rto'] = round(
old_div(float(count), float(len(words))), 4)
# Contextual Aspect Summary and Topical-Entity Recognition (CASTER)
if do_get_caster:
""" May incur a performance cost in time to process """
caster_dict = get_caster(text)
features['caster_dict'] = caster_dict
return features
def extract_bias_features(text):
features = OrderedDict()
text_nohyph = text.replace(
"-", " ") # preserve hyphenated words as seperate tokens
txt_lwr = str(text_nohyph).lower()
words = ''.join(ch for ch in txt_lwr
if ch not in '!"#$%&()*+,-./:;<=>?@[\]^_`{|}~').split()
unigrams = sorted(list(set(words)))
bigram_tokens = find_ngrams(words, 2)
bigrams = [" ".join([w1, w2]) for w1, w2 in sorted(set(bigram_tokens))]
trigram_tokens = find_ngrams(words, 3)
trigrams = [
" ".join([w1, w2, w3]) for w1, w2, w3 in sorted(set(trigram_tokens))
]
# word count
features['word_cnt'] = len(words)
# unique word count
features['unique_word_cnt'] = len(unigrams)
# presupposition verb count
count = count_feature_list_freq(presup, words, bigrams, trigrams)
features['presup_cnt'] = count
features['presup_rto'] = round(float(count) / float(len(words)), 4)
# coherence marker count
count = count_phrase_freq(coherence, txt_lwr)
features['cm_cnt'] = count
features['cm_rto'] = round(float(count) / float(len(words)), 4)
# assertive verb count
count = count_feature_list_freq(assertives, words, bigrams, trigrams)
features['assertive_cnt'] = count
features['assertive_rto'] = round(float(count) / float(len(words)), 4)
# degree modifier count
count = count_feature_list_freq(modifiers, words, bigrams, trigrams)
features['dm_cnt'] = count
features['dm_rto'] = round(float(count) / float(len(words)), 4)
# hedge word count
count = count_feature_list_freq(hedges, words, bigrams, trigrams)
features['hedge_cnt'] = count
features['hedge_rto'] = round(float(count) / float(len(words)), 4)
# partisan words and phrases count
count = count_feature_list_freq(partisan, words, bigrams, trigrams)
features['partisan_cnt'] = count
features['partisan_rto'] = round(float(count) / float(len(words)), 4)
# subjective value laden word count
count = count_feature_list_freq(value_laden, words, bigrams, trigrams)
features['opinion_cnt'] = count
features['opinion_rto'] = round(float(count) / float(len(words)), 4)
# compound sentiment score using VADER sentiment analysis package
compound_sentiment = vader_sentiment_analysis.polarity_scores(
text)['compound']
features['vader_sentiment'] = compound_sentiment
features['vader_senti_abs'] = abs(compound_sentiment)
# modality (certainty) score and mood using http://www.clips.ua.ac.be/pages/pattern-en#modality
sentence = parse(text, lemmata=True)
sentence_obj = Sentence(sentence)
features['modality'] = round(modality(sentence_obj), 4)
# Flesch-Kincaid Grade Level (reading difficulty) using textstat
features['fk_gl'] = flesch_kincaid_grade(text)
# figurative count
count = count_phrase_freq(figurative, txt_lwr)
features['figurative_cnt'] = count
features['figurative_rto'] = round(float(count) / float(len(words)), 4)
# liwc 3rd person pronoun count (combines S/he and They)
count = count_liwc_list_freq(liwc_3pp, words)
features['liwc_3pp_cnt'] = count
features['liwc_3pp_rto'] = round(float(count) / float(len(words)), 4)
# liwc achievement word count
count = count_liwc_list_freq(liwc_achiev, words)
features['liwc_achiev_cnt'] = count
features['liwc_achiev_rto'] = round(float(count) / float(len(words)), 4)
# liwc causation word count
count = count_liwc_list_freq(liwc_causn, words)
features['liwc_causn_cnt'] = count
features['liwc_causn_rto'] = round(float(count) / float(len(words)), 4)
# liwc self reference promouns count
count = count_liwc_list_freq(liwc_self, words)
features['liwc_self_cnt'] = count
features['liwc_self_rto'] = round(float(count) / float(len(words)), 4)
# liwc tentative word count
count = count_liwc_list_freq(liwc_tent, words)
features['liwc_tent_cnt'] = count
features['liwc_tent_rto'] = round(float(count) / float(len(words)), 4)
# liwc work word count
count = count_liwc_list_freq(liwc_work, words)
features['liwc_work_cnt'] = count
features['liwc_work_rto'] = round(float(count) / float(len(words)), 4)
# handle quoted material in text
quote_dict = check_quotes(text)
features["has_quotes"] = quote_dict["has_quotes"]
features["mean_quote_length"] = quote_dict["mean_quote_length"]
features["mean_nonquote_length"] = quote_dict["mean_nonquote_length"]
return features