import pymc3 as pm
import arviz as az
import numpy as np
import matplotlib.pyplot as plt
x1 = np.array([3.25466863, 2.97370402, 2.91113498, 3.4574893 , 3.17937048,
3.03048094, 3.21812428, 2.81350504, 2.9976349 , 2.97788408,
3.1813029 , 2.87498481, 2.90372449, 3.46095383, 3.11570786,
2.69100383, 2.97142051, 2.72968174, 2.48244642, 2.8584929 ])
x1
x2 = np.array([3.58365047, 3.04506491, 3.35190893, 2.76485786, 3.8494015 ,
3.17593123, 3.03499338, 2.31533078, 2.58647626, 3.47397813,
2.9985396 , 3.46170964, 3.23908075, 2.78904992, 3.000179 ,
3.23386923, 3.10856455, 3.24167989, 2.92353227, 3.09131427])
x2
x1_mean = x1.mean()
x2_mean = x2.mean()
print("<x1>=%4.3f <x2>=%4.3f -> <x2-x1> = %4.3f" % (x1_mean, x2_mean, x2_mean-x1_mean))
<x1>=3.004 <x2>=3.113 -> <x2-x1> = 0.109