我写了一个简单的文档分类器,目前我正在布朗语料库上测试它。但是,我的准确度仍然很低(0.16)。我已经排除了停用词。关于如何提高分类器性能的其他想法?提高准确性朴素贝叶斯分类器
import nltk, random
from nltk.corpus import brown, stopwords
documents = [(list(brown.words(fileid)), category)
for category in brown.categories()
for fileid in brown.fileids(category)]
random.shuffle(documents)
stop = set(stopwords.words('english'))
all_words = nltk.FreqDist(w.lower() for w in brown.words() if w in stop)
word_features = list(all_words.keys())[:3000]
def document_features(document):
document_words = set(document)
features = {}
for word in word_features:
features['contains(%s)' % word] = (word in document_words)
return features
featuresets = [(document_features(d), c) for (d,c) in documents]
train_set, test_set = featuresets[100:], featuresets[:100]
classifier = nltk.NaiveBayesClassifier.train(train_set)
print(nltk.classify.accuracy(classifier, test_set))
我想有一个与代码版中的问题,似乎有两行分类= NLTK之前评论...正在要求。顺便说一句,这不使用朴素贝叶斯分类器,而是一个决策树分类器,所以你应该改变标签和标题。 –
你不排除停用词,你只包括他们。 变化:' 到 'all_words = nltk.FreqDist(w.lower 'all_words = nltk.FreqDist(为w的brown.words()当w在停止w.lower)为w的棕色。文字()如果W不在停止)' –