I get this error when I try to import linearmodels: "numpy.ndarray size changed, may indicate binary incompatibility. Expected 88 from C header, got 80 from PyObject"
I run Anaconda, python 3.8.8 on Windows 10. It is a fresh installation of Anaconda Python on a new machine.
I tried to solve this problem by using an older NumPy version (1.6.1, see this link) in a separate environment. Alas.
This is the output that shows which versions of libraries I use, and note the real path is not c:\users\, but c:\users\myusername\
Requirement already satisfied: linearmodels in c:\users\anaconda3\lib\site-packages (4.21)
Requirement already satisfied: pandas>=0.24 in c:\users\anaconda3\lib\site-packages (from linearmodels) (1.2.3)
Requirement already satisfied: pyhdfe>=0.1 in c:\users\anaconda3\lib\site-packages (from linearmodels) (0.1.0)
Requirement already satisfied: scipy>=1.2 in c:\users\anaconda3\lib\site-packages (from linearmodels) (1.6.1)
Requirement already satisfied: statsmodels>=0.11 in c:\users\anaconda3\lib\site-packages (from linearmodels) (0.12.2)
Requirement already satisfied: mypy-extensions>=0.4 in c:\users\anaconda3\lib\site-packages (from linearmodels) (0.4.3)
Requirement already satisfied: property-cached>=1.6.3 in c:\users\anaconda3\lib\site-packages (from linearmodels) (1.6.4)
Requirement already satisfied: numpy>=1.16 in c:\users\anaconda3\lib\site-packages (from linearmodels) (1.19.2)
Requirement already satisfied: patsy in c:\users\anaconda3\lib\site-packages (from linearmodels) (0.5.1)
Requirement already satisfied: Cython>=0.29.21 in c:\users\anaconda3\lib\site-packages (from linearmodels) (0.29.22)
Requirement already satisfied: python-dateutil>=2.7.3 in c:\users\anaconda3\lib\site-packages (from pandas>=0.24->linearmodels) (2.8.1)
Requirement already satisfied: pytz>=2017.3 in c:\users\anaconda3\lib\site-packages (from pandas>=0.24->linearmodels) (2021.1)
Requirement already satisfied: six>=1.5 in c:\users\anaconda3\lib\site-packages (from python-dateutil>=2.7.3->pandas>=0.24->linearmodels) (1.15.0)
This is what proceeds he error:
from linearmodels import PanelOLS
Traceback (most recent call last):
File "<ipython-input-2-6de63ba6aa3f>", line 1, in <module>
from linearmodels import PanelOLS
File "C:\Users\Anaconda3\lib\site-packages\linearmodels\__init__.py", line 38, in <module>
from .asset_pricing.model import (
File "C:\Users\Anaconda3\lib\site-packages\linearmodels\asset_pricing\__init__.py", line 1, in <module>
from .model import LinearFactorModel, LinearFactorModelGMM, TradedFactorModel
File "C:\Users\Anaconda3\lib\site-packages\linearmodels\asset_pricing\model.py", line 13, in <module>
from linearmodels.asset_pricing.covariance import (
File "C:\Users\Anaconda3\lib\site-packages\linearmodels\asset_pricing\covariance.py", line 9, in <module>
from linearmodels.iv.covariance import (
File "C:\Users\Anaconda3\lib\site-packages\linearmodels\iv\__init__.py", line 1, in <module>
from .absorbing import AbsorbingLS, Interaction # flake8: noqa
File "C:\Users\Anaconda3\lib\site-packages\linearmodels\iv\absorbing.py", line 54, in <module>
from linearmodels.panel.utility import (
File "C:\Users\Anaconda3\lib\site-packages\linearmodels\panel\__init__.py", line 1, in <module>
from linearmodels.panel.model import (
File "C:\Users\Anaconda3\lib\site-packages\linearmodels\panel\model.py", line 28, in <module>
from linearmodels.panel.utility import (
File "C:\Users\Anaconda3\lib\site-packages\linearmodels\panel\utility.py", line 24, in <module>
from linearmodels.panel._utility import _drop_singletons
File "linearmodels\panel\_utility.pyx", line 1, in init linearmodels.panel._utility
ValueError: numpy.ndarray size changed, may indicate binary incompatibility. Expected 88 from C header, got 80 from PyObject
This has been solved by updating to the latest linearmodels version: 4.22