停用词

Python 中的情感分析

Violeta Misheva

Data Scientist

什么是停用词，如何找到？

停用词：出现过于频繁、信息量低的词

大多数语言都有停用词表

  {'the', 'a', 'an', 'and', 'but', 'for', 'on', 'in', 'at' ...}

语境很重要

  {'movie', 'movies', 'film', 'films', 'cinema'}

结合词云看停用词

未去除停用词的词云

去除停用词后的词云

从词云中移除停用词

# Import libraries
from wordcloud import WordCloud, STOPWORDS
import matplotlib.pyplot as plt

# Define the stopwords list
my_stopwords = set(STOPWORDS)
my_stopwords.update(["movie", "movies", "film", "films", "watch", "br"])

# Generate and show the word cloud
my_cloud = WordCloud(background_color='white', stopwords=my_stopwords).generate(name_string)
plt.imshow(my_cloud, interpolation='bilinear')

BOW 中的停用词

from sklearn.feature_extraction.text import CountVectorizer, ENGLISH_STOP_WORDS

# Define the set of stop words
my_stop_words = ENGLISH_STOP_WORDS.union(['film', 'movie', 'cinema', 'theatre'])

vect = CountVectorizer(stop_words=my_stop_words) 
vect.fit(movies.review)
X = vect.transform(movies.review)

让我们练习！

Python 中的情感分析