Seaborn distplot y轴标准化错误的ticklabels

Question

请注意,我已经检查了这个问题和这个问题.

所以,我正在使用distplot在单独的子图上绘制一些直方图:

import numpy as np
#import netCDF4 as nc # used to get p0_dict
import matplotlib.pyplot as plt
from collections import OrderedDict
import seaborn.apionly as sns
import cPickle as pickle

''' 
LINK TO PICKLE
https://drive.google.com/file/d/0B8Xks3meeDq0aTFYcTZEZGFFVk0/view?usp=sharing
'''

p0_dict = pickle.load(open('/path/to/pickle/test.dat', 'r'))     

fig = plt.figure(figsize = (15,10))
ax = plt.gca()
j=1

for region, val in p0_dict.iteritems():

    val = np.asarray(val)

    subax = plt.subplot(5,5,j)

    print region

    try:              
        sns.distplot(val, bins=11, hist=True, kde=True, rug=True, 
                     ax = subax, color = 'k', norm_hist=True)

    except Exception as Ex:
        print Ex

    subax.set_title(region)
    subax.set_xlim(0, 1) # the data varies from 0 to 1

    j+=1    

plt.subplots_adjust(left = 0.06, right = 0.99, bottom = 0.07,
                    top = 0.92, wspace = 0.14, hspace = 0.6) 

fig.text(0.5, 0.02, r'$ P(W) = 0,1 $', ha ='center', fontsize = 15)
fig.text(0.02, 0.5, '% occurrence', ha ='center', 
         rotation='vertical', fontsize = 15) 
# obviously I'd multiply the fractional ticklabels by 100 to get 
# the percentage...

plt.show()

我期望KDE曲线下面积总和为1,y轴刻度标签反映这一点.但是,我得到以下内容:

如您所见,y轴刻度标记不在[0,1]范围内,如预期的那样.打开/关闭norm_hist或kde不更改此设置.作为参考,两个输出均关闭:

只是为了验证:

aus = np.asarray(p0_dict['AUS'])
aus_bins = np.histogram(aus, bins=11)[0]

plt.subplot(121)
plt.hist(aus,11)
plt.subplot(122)
plt.bar(range(0,11),aus_bins.astype(np.float)/np.sum(aus_bins))

plt.show()

在这种情况下,y刻度标签正确地反映了标准化直方图的那些.

我究竟做错了什么？

谢谢您的帮助.

Answer 1

y轴是密度,而不是概率.我认为你期望标准化的直方图显示概率质量函数,其中条形高度的总和等于1.但这是错误的; 标准化确保条形高度的总和乘以条形宽度等于1.这可以确保标准化直方图与核密度估计相当,后者被标准化以使曲线下面积等于1.