Gapminder#

in English or the language of your choice.

import japanize_matplotlib
import matplotlib.pyplot as plt
import numpy as np
import pandas as pd
import py4macro
from gapminder import gapminder

# 警告メッセージを非表示
import warnings
warnings.filterwarnings("ignore")

Gapminderとは世界規模で見た経済格差をデータで探る有名なサイトであり、一見の価値があるサイトである。そのサイトで使われているデータを整理してパッケージにまとめたのがgapminderである。

Note

MacではTerminal、WindowsではGit Bashを使い、次のコマンドでgapminderをインストールできる。

pip install gapminder

ここではgapminderに含まれるデータを使いpandasgroupbyというDataFrameのメソッドの使い方の例を紹介する。両方ともデータをグループ化して扱う場合に非常に重宝するので、覚えておいて損はしないだろう。

データ#

<列ラベル>

  • country:国名

  • continent:大陸

  • year:年

  • lifeExp:平均寿命

  • pop:人口

  • gdpPercap:一人当たりGDP(国内総生産)

データの読み込みと最初の5行の表示

df = gapminder
df.head()
country continent year lifeExp pop gdpPercap
0 Afghanistan Asia 1952 28.801 8425333 779.445314
1 Afghanistan Asia 1957 30.332 9240934 820.853030
2 Afghanistan Asia 1962 31.997 10267083 853.100710
3 Afghanistan Asia 1967 34.020 11537966 836.197138
4 Afghanistan Asia 1972 36.088 13079460 739.981106

最後の5行の表示

df.tail()
country continent year lifeExp pop gdpPercap
1699 Zimbabwe Africa 1987 62.351 9216418 706.157306
1700 Zimbabwe Africa 1992 60.377 10704340 693.420786
1701 Zimbabwe Africa 1997 46.809 11404948 792.449960
1702 Zimbabwe Africa 2002 39.989 11926563 672.038623
1703 Zimbabwe Africa 2007 43.487 12311143 469.709298

データセットの内容確認

df.info()
<class 'pandas.core.frame.DataFrame'>
RangeIndex: 1704 entries, 0 to 1703
Data columns (total 6 columns):
 #   Column     Non-Null Count  Dtype  
---  ------     --------------  -----  
 0   country    1704 non-null   object 
 1   continent  1704 non-null   object 
 2   year       1704 non-null   int64  
 3   lifeExp    1704 non-null   float64
 4   pop        1704 non-null   int64  
 5   gdpPercap  1704 non-null   float64
dtypes: float64(2), int64(2), object(2)
memory usage: 80.0+ KB

記述統計の表示

df.describe()
year lifeExp pop gdpPercap
count 1704.00000 1704.000000 1.704000e+03 1704.000000
mean 1979.50000 59.474439 2.960121e+07 7215.327081
std 17.26533 12.917107 1.061579e+08 9857.454543
min 1952.00000 23.599000 6.001100e+04 241.165876
25% 1965.75000 48.198000 2.793664e+06 1202.060309
50% 1979.50000 60.712500 7.023596e+06 3531.846988
75% 1993.25000 70.845500 1.958522e+07 9325.462346
max 2007.00000 82.603000 1.318683e+09 113523.132900

含まれる国名の表示

countries = df.loc[:,'country'].unique()
countries
array(['Afghanistan', 'Albania', 'Algeria', 'Angola', 'Argentina',
       'Australia', 'Austria', 'Bahrain', 'Bangladesh', 'Belgium',
       'Benin', 'Bolivia', 'Bosnia and Herzegovina', 'Botswana', 'Brazil',
       'Bulgaria', 'Burkina Faso', 'Burundi', 'Cambodia', 'Cameroon',
       'Canada', 'Central African Republic', 'Chad', 'Chile', 'China',
       'Colombia', 'Comoros', 'Congo, Dem. Rep.', 'Congo, Rep.',
       'Costa Rica', "Cote d'Ivoire", 'Croatia', 'Cuba', 'Czech Republic',
       'Denmark', 'Djibouti', 'Dominican Republic', 'Ecuador', 'Egypt',
       'El Salvador', 'Equatorial Guinea', 'Eritrea', 'Ethiopia',
       'Finland', 'France', 'Gabon', 'Gambia', 'Germany', 'Ghana',
       'Greece', 'Guatemala', 'Guinea', 'Guinea-Bissau', 'Haiti',
       'Honduras', 'Hong Kong, China', 'Hungary', 'Iceland', 'India',
       'Indonesia', 'Iran', 'Iraq', 'Ireland', 'Israel', 'Italy',
       'Jamaica', 'Japan', 'Jordan', 'Kenya', 'Korea, Dem. Rep.',
       'Korea, Rep.', 'Kuwait', 'Lebanon', 'Lesotho', 'Liberia', 'Libya',
       'Madagascar', 'Malawi', 'Malaysia', 'Mali', 'Mauritania',
       'Mauritius', 'Mexico', 'Mongolia', 'Montenegro', 'Morocco',
       'Mozambique', 'Myanmar', 'Namibia', 'Nepal', 'Netherlands',
       'New Zealand', 'Nicaragua', 'Niger', 'Nigeria', 'Norway', 'Oman',
       'Pakistan', 'Panama', 'Paraguay', 'Peru', 'Philippines', 'Poland',
       'Portugal', 'Puerto Rico', 'Reunion', 'Romania', 'Rwanda',
       'Sao Tome and Principe', 'Saudi Arabia', 'Senegal', 'Serbia',
       'Sierra Leone', 'Singapore', 'Slovak Republic', 'Slovenia',
       'Somalia', 'South Africa', 'Spain', 'Sri Lanka', 'Sudan',
       'Swaziland', 'Sweden', 'Switzerland', 'Syria', 'Taiwan',
       'Tanzania', 'Thailand', 'Togo', 'Trinidad and Tobago', 'Tunisia',
       'Turkey', 'Uganda', 'United Kingdom', 'United States', 'Uruguay',
       'Venezuela', 'Vietnam', 'West Bank and Gaza', 'Yemen, Rep.',
       'Zambia', 'Zimbabwe'], dtype=object)

国の数の確認

len(countries)
142

2007年におけるcontinentの内訳(国の数)

cond = ( df['year']==df['year'].max() )
df.loc[cond,:].value_counts('continent')
continent
Africa      52
Asia        33
Europe      30
Americas    25
Oceania      2
Name: count, dtype: int64

割合で表すと

cond = ( df['year']==df['year'].max() )
df.loc[cond,:].value_counts('continent', normalize=True)
continent
Africa      0.366197
Asia        0.232394
Europe      0.211268
Americas    0.176056
Oceania     0.014085
Name: proportion, dtype: float64

groupby()#

df_group = df.groupby('continent')

属性を調べてみよう。

py4macro.see(df_group)
.agg                .aggregate          .all                .any
.apply              .bfill              .boxplot            .continent
.corr               .corrwith           .count              .country
.cov                .cumcount           .cummax             .cummin
.cumprod            .cumsum             .describe           .diff
.dtypes             .ewm                .expanding          .ffill
.fillna             .filter             .first              .gdpPercap
.get_group          .groups             .head               .hist
.idxmax             .idxmin             .indices            .last
.lifeExp            .max                .mean               .median
.min                .ndim               .ngroup             .ngroups
.nth                .nunique            .ohlc               .pct_change
.pipe               .plot               .pop                .prod
.quantile           .rank               .resample           .rolling
.sample             .sem                .shift              .size
.skew               .std                .sum                .tail
.take               .transform          .value_counts       .var
.year

continentの内訳(again)#

country_names = df_group['country'].nunique()
country_names
continent
Africa      52
Americas    25
Asia        33
Europe      30
Oceania      2
Name: country, dtype: int64

統計量#

three_vars=['lifeExp','pop','gdpPercap']

観測値の数#

大陸別の観測値の数

df_group.size()
continent
Africa      624
Americas    300
Asia        396
Europe      360
Oceania      24
dtype: int64

棒グラフ

ax = df_group.size().plot(kind='bar')
ax.set_title('大陸別の観測値の数', size=15)
pass
_images/b83fab05cebdff117951fa77368f7d67561a0113ec135b94d266e65762744126.png

変数別での観測値の数

df_group.count()
country year lifeExp pop gdpPercap
continent
Africa 624 624 624 624 624
Americas 300 300 300 300 300
Asia 396 396 396 396 396
Europe 360 360 360 360 360
Oceania 24 24 24 24 24

平均#

それぞれの変数の平均(文字列のcountryを含めるとエラーが発生するためthree_varsを指定する。)

df_group[three_vars].mean()
lifeExp pop gdpPercap
continent
Africa 48.865330 9.916003e+06 2193.754578
Americas 64.658737 2.450479e+07 7136.110356
Asia 60.064903 7.703872e+07 7902.150428
Europe 71.903686 1.716976e+07 14469.475533
Oceania 74.326208 8.874672e+06 18621.609223

gdpPercaplifeExpの大陸別平均の散布図

ax = df_group[three_vars].mean().plot(kind='scatter', x='gdpPercap', y='lifeExp')
ax.set_title('gdpPercapとlifeExpの\n大陸別平均の散布図', size=20)
pass
_images/7ea4a2cdac68593a891e0c29e02e03863b0eca09656061b2ffce5a0ed5648786.png

標準偏差#

それぞれの変数の標準偏差

df_group[three_vars].std()
lifeExp pop gdpPercap
continent
Africa 9.150210 1.549092e+07 2827.929863
Americas 9.345088 5.097943e+07 6396.764112
Asia 11.864532 2.068852e+08 14045.373112
Europe 5.433178 2.051944e+07 9355.213498
Oceania 3.795611 6.506342e+06 6358.983321

最大値#

df_group.max()
country year lifeExp pop gdpPercap
continent
Africa Zimbabwe 2007 76.442 135031164 21951.21176
Americas Venezuela 2007 80.653 301139947 42951.65309
Asia Yemen, Rep. 2007 82.603 1318683096 113523.13290
Europe United Kingdom 2007 81.757 82400996 49357.19017
Oceania New Zealand 2007 81.235 20434176 34435.36744

最小値#

df_group.min()
country year lifeExp pop gdpPercap
continent
Africa Algeria 1952 23.599 60011 241.165876
Americas Argentina 1952 37.579 662850 1201.637154
Asia Afghanistan 1952 28.801 120447 331.000000
Europe Albania 1952 43.585 147962 973.533195
Oceania Australia 1952 69.120 1994794 10039.595640

3変数の記述統計#

df_group[three_vars].describe().map("{0:.1f}".format).T
continent Africa Americas Asia Europe Oceania
lifeExp count 624.0 300.0 396.0 360.0 24.0
mean 48.9 64.7 60.1 71.9 74.3
std 9.2 9.3 11.9 5.4 3.8
min 23.6 37.6 28.8 43.6 69.1
25% 42.4 58.4 51.4 69.6 71.2
50% 47.8 67.0 61.8 72.2 73.7
75% 54.4 71.7 69.5 75.5 77.6
max 76.4 80.7 82.6 81.8 81.2
pop count 624.0 300.0 396.0 360.0 24.0
mean 9916003.1 24504795.0 77038722.0 17169764.7 8874672.3
std 15490923.3 50979430.2 206885204.6 20519437.6 6506342.5
min 60011.0 662850.0 120447.0 147962.0 1994794.0
25% 1342075.0 2962358.8 3844393.0 4331500.0 3199212.5
50% 4579311.0 6227510.0 14530830.5 8551125.0 6403491.5
75% 10801489.8 18340309.0 46300348.0 21802867.0 14351625.0
max 135031164.0 301139947.0 1318683096.0 82400996.0 20434176.0
gdpPercap count 624.0 300.0 396.0 360.0 24.0
mean 2193.8 7136.1 7902.2 14469.5 18621.6
std 2827.9 6396.8 14045.4 9355.2 6359.0
min 241.2 1201.6 331.0 973.5 10039.6
25% 761.2 3427.8 1057.0 7213.1 14141.9
50% 1192.1 5465.5 2646.8 12081.7 17983.3
75% 2377.4 7830.2 8549.3 20461.4 22214.1
max 21951.2 42951.7 113523.1 49357.2 34435.4

groupby.agg()#

agg()を使うと複数のメソッドを同時に使うことができる。この場合は,メソッド名を文字列として引数として使う。

df_group[three_vars].agg("mean")
lifeExp pop gdpPercap
continent
Africa 48.865330 9.916003e+06 2193.754578
Americas 64.658737 2.450479e+07 7136.110356
Asia 60.064903 7.703872e+07 7902.150428
Europe 71.903686 1.716976e+07 14469.475533
Oceania 74.326208 8.874672e+06 18621.609223
df_group[three_vars].agg(["max", "min", "mean"])
lifeExp pop gdpPercap
max min mean max min mean max min mean
continent
Africa 76.442 23.599 48.865330 135031164 60011 9.916003e+06 21951.21176 241.165876 2193.754578
Americas 80.653 37.579 64.658737 301139947 662850 2.450479e+07 42951.65309 1201.637154 7136.110356
Asia 82.603 28.801 60.064903 1318683096 120447 7.703872e+07 113523.13290 331.000000 7902.150428
Europe 81.757 43.585 71.903686 82400996 147962 1.716976e+07 49357.19017 973.533195 14469.475533
Oceania 81.235 69.120 74.326208 20434176 1994794 8.874672e+06 34435.36744 10039.595640 18621.609223

自作の関数も使用することができる。この場合は,関数名だけを使う(文字列ではない)。

func = lambda x: ( np.max(x)-np.min(x) )/np.mean(x)

df_group[['lifeExp','pop','gdpPercap']].agg(func)
lifeExp pop gdpPercap
continent
Africa 1.081401 13.611447 9.896297
Americas 0.666174 12.261971 5.850528
Asia 0.895731 17.115583 14.324219
Europe 0.530877 4.790574 3.343843
Oceania 0.162998 2.077754 1.310079

continentの内訳の割合を計算

#

continent平均寿命

df_lifeExp_continent = df_group['lifeExp'].mean()
ax = df_lifeExp_continent.plot(kind='bar')
ax.set_title('大陸別平均寿命', size=15)
pass
_images/7057b34eeb316a722a6dba7d032c0d8fd8c4d164af577f71b973add48ddbaa5f.png

3つの変数#

df_mean = df_group[three_vars].mean()
df_mean['ln_pop'] = np.log( df_mean['pop'] )
df_mean['ln_gdpPercap'] = df_mean['gdpPercap'].apply(np.log)
df_mean['lifeExp_10'] = df_mean['lifeExp']/10
df_mean[['ln_pop','lifeExp_10', 'ln_gdpPercap']].plot(kind='bar')
pass
_images/5349bf2f7d3cf8c2dd442068a4c834d8f43d28c70981c3d1e4500f212506e0fc.png

複数階層のgroupby()#

continent別の平均時系列を考えるときに有用。

df_group2 = df.groupby(['continent','year'])
df_group2[three_vars].mean().head()
lifeExp pop gdpPercap
continent year
Africa 1952 39.135500 4.570010e+06 1252.572466
1957 41.266346 5.093033e+06 1385.236062
1962 43.319442 5.702247e+06 1598.078825
1967 45.334538 6.447875e+06 2050.363801
1972 47.450942 7.305376e+06 2339.615674

lifeExpの列だけを選択した後,.unstack()を使ってyearが行ラベルになるDataFrameに変換してみる。

df_lifeExp_group = df_group2[three_vars].mean().loc[:,'lifeExp'].unstack(level=0)
ax = df_lifeExp_group.plot()
ax.set_title('大陸別平均寿命の推移', size=15)
pass
_images/a919c3767edf3f05e42cf7951856a28ab2cadeb21458d6ac22279bc6dc7e62af.png

世界平均との比較

df_group_year = df.groupby('year')
world_lifeExp = df_group_year[three_vars].mean()['lifeExp'].to_numpy().reshape(1,12).T
df_lifeExp_diff = df_lifeExp_group - world_lifeExp

ax = df_lifeExp_diff.plot()
ax.set_title('大陸別平均寿命の世界平均との差の推移', size=15)
pass
_images/22aeddc944713762fc439f9fb982b9af1f0ff1bf5c08196b29ec63ec2824a438.png