Google colab有一些与贝叶斯分析和相应的库相关的问题

Question

我正在研究Bayessian analysis with python这本书，并试图用python实现所有代码，为此我使用google colab，但当我运行书中的代码时

import arviz
import pymc3 as pm
import numpy as np
from scipy import stats
np.random.seed(123)
n_experiments=4
theta_real =0.35
data =stats.bernoulli.rvs(p=theta_real,size=n_experiments)
with pm.Model()  as our_first_model:
    theta =pm.Beta('theta',alpha=1,beta=1)
    y =pm.Bernoulli('y',p=theta,observed=data)
    start =pm.find_MAP()
    step =pm.Metropolis()
    trace =pm.sample(1000,step=step,start=start)
    burnin=100
    chain =trace[burnin:]
    pm.traceplot(chain,lines={'theta':theta_real})

它会给出这样的错误：

AttributeError: Installed version of ArviZ requires PyMC3>=3.8. Please upgrade with `pip install pymc3>=3.8` or `conda install -c conda-forge pymc3>=3.8`

在我尝试实现这些库之前

!pip install pymc3>=3.8
!pip install arviz

但还是没有成功。如何修复此错误？

Answer 1

您是否已尝试重新启动会话？一旦您使用!pip install pymc3>=3.8升级，您将不得不重新启动会话，然后执行import pymc3 as pm，否则它仍将考虑以前安装的版本。