我在使用pandas读取一个Excel表格,该表格有超过10列,我只对其中的3列感兴趣,所以我读取它,删除了包含空值的行,然后创建了测试集和验证集。在将其拟合到逻辑回归模型时,我遇到了一个错误
这是代码
train, tv = train_test_split(df1, test_size=0.2, random_state=0)test, val = train_test_split(tv, test_size=0.5, random_state=0)# Logistic Regressionlr = LogisticRegression()logit_model = lr.fit(train, test)
堆栈跟踪:
Traceback (most recent call last): File "ml.py", line 22, in <module> logit_model = lr.fit(train, test) File "F:\proj\venv\lib\site-packages\sklearn\linear_model\_logistic.py", line 1344, in fit X, y = self._validate_data(X, y, accept_sparse='csr', dtype=_dtype, File "F:\proj\venv\lib\site-packages\sklearn\base.py", line 433, in _validate_data X, y = check_X_y(X, y, **check_params) File "F:\proj\venv\lib\site-packages\sklearn\utils\validation.py", line 63, in inner_f return f(*args, **kwargs) File "F:\proj\venv\lib\site-packages\sklearn\utils\validation.py", line 871, in check_X_y X = check_array(X, accept_sparse=accept_sparse, File "F:\proj\venv\lib\site-packages\sklearn\utils\validation.py", line 63, in inner_f return f(*args, **kwargs) File "F:\proj\venv\lib\site-packages\sklearn\utils\validation.py", line 673, in check_array array = np.asarray(array, order=order, dtype=dtype) File "F:\proj\venv\lib\site-packages\pandas\core\generic.py", line 1990, in __array__ return np.asarray(self._values, dtype=dtype)ValueError: could not convert string to float: 'Yes, policy'
数据框看起来像这样:
ID ANSWER TEXT0 24100.0 Yes, policy Source text snippet:The ACS Group combines its...1 24100.0 Yes, policy Source text snippet:The ACS Environmental Poli...2 24100.0 Yes, policy Source text snippet:The ACS Environmental Poli...3 24100.0 Yes, policy Source text snippet:6. CONTENTS OF THE ENVIRON...4 24100.0 Yes, policy Source text snippet:6. CONTENTS OF THE ENVIRON...
通过查看ValueError,我认为可能是由于Answer列中”Yes”后的逗号引起的,但即使删除了它,仍然出现相同的错误。Excel中的ID看起来是24100,但在数据框中检查其类型时显示为float64,并显示为24100.0。我不明白为什么在将其拟合到模型上时会抛出错误。
回答:
看起来你的ANSWER
和TEXT
列包含分类值,你需要在将其输入模型之前将其编码为数值形式。因为机器学习模型无法理解文本。在使用train_test_split
之前,对数据框使用以下代码
from sklearn.preprocessing import LabelEncoder df['TEXT'] = df['TEXT'].astype('str') df['ANSWER'] = df['ANSWER'].astype('str') df[['ANSWER', 'TEXT']] = df[['ANSWER', 'TEXT']].apply(LabelEncoder().fit_transform)
另外,这是一个多类分类问题,因此Logistic Regression
不会给你很好的结果。请使用RandomForestClassifier
。