AttributeError: LinearRegression object has no attribute 'coef_'

Question

I've been attempting to fit this data by a Linear Regression, following a tutorial on bigdataexaminer. Everything was working fine up until this point. I imported LinearRegression from sklearn, and printed the number of coefficients just fine. This was the code before I attempted to grab the coefficients from the console.

import numpy as np
import pandas as pd
import scipy.stats as stats
import matplotlib.pyplot as plt
import sklearn
from sklearn.datasets import load_boston
from sklearn.linear_model import LinearRegression

boston = load_boston()
bos = pd.DataFrame(boston.data)
bos.columns = boston.feature_names
bos['PRICE'] = boston.target

X = bos.drop('PRICE', axis = 1)

lm = LinearRegression()

After I had all this set up I ran the following command, and it returned the proper output:

In [68]: print('Number of coefficients:', len(lm.coef_)

Number of coefficients: 13

However, now if I ever try to print this same line again, or use 'lm.coef_', it tells me coef_ isn't an attribute of LinearRegression, right after I JUST used it successfully, and I didn't touch any of the code before I tried it again.

In [70]: print('Number of coefficients:', len(lm.coef_))

Traceback (most recent call last):

 File "<ipython-input-70-5ad192630df3>", line 1, in <module>
print('Number of coefficients:', len(lm.coef_))

AttributeError: 'LinearRegression' object has no attribute 'coef_'

Answer 1

调用dt方法时会创建coef_属性。在此之前，它将是未定义的：

fit()

如果我们调用>>> import numpy as np >>> import pandas as pd >>> from sklearn.datasets import load_boston >>> from sklearn.linear_model import LinearRegression >>> boston = load_boston() >>> lm = LinearRegression() >>> lm.coef_ --------------------------------------------------------------------------- AttributeError Traceback (most recent call last) <ipython-input-22-975676802622> in <module>() 7 8 lm = LinearRegression() ----> 9 lm.coef_ AttributeError: 'LinearRegression' object has no attribute 'coef_' ，系数将被定义：

fit()

我的猜测是，当您运行有问题的行时，您忘记拨打>>> lm.fit(boston.data, boston.target) >>> lm.coef_ array([ -1.07170557e-01, 4.63952195e-02, 2.08602395e-02, 2.68856140e+00, -1.77957587e+01, 3.80475246e+00, 7.51061703e-04, -1.47575880e+00, 3.05655038e-01, -1.23293463e-02, -9.53463555e-01, 9.39251272e-03, -5.25466633e-01]) 。