用 Kaggle 數據集來分析幸福指數

本文作者： AI研習社-譯站

2018-06-21 15:58

導語：我們選擇了 2017 幸福度數集，一個來自 Kaggle 平臺的數據集。

本文為雷鋒網字幕組編譯的技術博客 Happiness 2017，作者為 Javad Zabihi。
翻譯 | Binpluto 整理 | 孔令雙

雷鋒網 AI 研習社：我們選擇了 2017 幸福度數集，一個來自 Kaggle 平臺的數集。這份數集給出了來自世界 155 個國家，關于包括家庭狀況，平均壽命，經濟水平，寬容度，對政府的信任感，自由度和反烏托邦殘留在內的七方面因素的幸福等級和幸福值。這七項的分值之和就是幸福值，幸福值越高，幸福等級越低。因此，很顯然七項中的每一項分值越高，意味著幸福水平越高。我們將這七項因素定義為影響幸福的因素。反烏托邦是烏托邦的對立面，意味著最低的幸福水平。它將被視為其他國家判斷他們離最不幸福國家有多遠的參考對象。

我的報告包含了以下三部分：

凈化
可視化
預測

任務

選擇這項任務的目的在于找出，哪些因素對人們過上幸福的生活更重要。根據結果，人們和國家可以專注于更關鍵的因素來實現更高的幸福水準。我們也將運用不同的機器學習算法來預測幸福值并比較預測結果，來判斷哪一種算法更適用于這個數集。

凈化

現在我們可以導入數集并觀察幸福變量的結構。我們的數集已經相當的整潔，不過，我們仍將會作出一點調整來使它看起來更好。

library(plyr)
library(dplyr)
library(tidyverse)
library(lubridate)
library(caTools)
library(ggplot2)
library(ggthemes)
library(reshape2)
library(data.table)
library(tidyr)
library(corrgram)
library(corrplot)
library(formattable)
library(cowplot)
library(ggpubr)
library(plot3D)

# World happiness report 2017
Happiness <- read.csv("../input/2017.csv")
str(Happiness)

## 'data.frame': 155 obs. of 12 variables:
## $ Country : Factor w/ 155 levels "Afghanistan",..: 105 38 58 133 45 99 26 100 132 7 ...
## $ Happiness.Rank : int 1 2 3 4 5 6 7 8 9 10 ...
## $ Happiness.Score : num 7.54 7.52 7.5 7.49 7.47 ...
## $ Whisker.high : num 7.59 7.58 7.62 7.56 7.53 ...
## $ Whisker.low : num 7.48 7.46 7.39 7.43 7.41 ...
## $ Economy..GDP.per.Capita. : num 1.62 1.48 1.48 1.56 1.44 ...
## $ Family : num 1.53 1.55 1.61 1.52 1.54 ...
## $ Health..Life.Expectancy. : num 0.797 0.793 0.834 0.858 0.809 ...
## $ Freedom : num 0.635 0.626 0.627 0.62 0.618 ...
## $ Generosity : num 0.362 0.355 0.476 0.291 0.245 ...
## $ Trust..Government.Corruption.: num 0.316 0.401 0.154 0.367 0.383 ...
## $ Dystopia.Residual : num 2.28 2.31 2.32 2.28 2.43 ...

我們已經觀察了包含在數集內的變量，他們對應的類，以及每一個變量中的前幾個觀察項。事實上，這個數集含有 155 個觀察項和 12 個變量。我認為一些變量名還不夠明了，于是決定改掉其中一些變量名。同時，盒須低和盒須高的變量將從數據集中移除，因為這些變量只能使幸福值的可靠區間變得更低或更高而對于可視化和預測方面沒有實際意義。

# Changing the name of columns
colnames (Happiness) <- c("Country", "Happiness.Rank", "Happiness.Score",
"Whisker.High", "Whisker.Low", "Economy", "Family",
"Life.Expectancy", "Freedom", "Generosity",
"Trust", "Dystopia.Residual")
# Country: Name of countries
# Happiness.Rank: Rank of the country based on the Happiness Score
# Happiness.Score: Happiness measurement on a scale of 0 to 10
# Whisker.High: Upper confidence interval of happiness score
# Whisker.Low: Lower confidence interval of happiness score
# Economy: The value of all final goods and services produced within a nation in a given year
# Per capita GDP is a measure of the total output of a country that takes the gross domestic product (GDP) and divides it by the number of people in that country. The per capita GDP is especially useful when comparing one country to another, because it shows the relative performance of the countries.
# Family: Importance of having a family
# Life.Expectancy: Importance of health and amount of time prople expect to live
# Freedom: Importance of freedom in each country
# Generosity: The quality of being kind and generous
# Trust: Perception of corruption in a government
# Dystopia.Residual: Plays as a reference

# Deleting unnecessary columns (Whisker.high and Whisker.low)

Happiness <- Happiness[, -c(4,5)]

下一步是在大洲的數據列表中添入另一列。我想要對不同的洲進行工作，以探究不同的因素對得到更高的幸福值是否會有不同的影響效果。亞洲，非洲，北美洲，南美洲，歐洲以及澳洲是數集里的六大洲。接著我將各大洲的這一列移到第二列，因為我認為這樣的布局安排會使得數據集更直觀。最后，我將大洲變量的數據類型改成指數型，這樣可以簡化可視化方面的工作。現在我們可以看到數集的最終結構，它包含了 155 個觀察項和 11 個變量。國家和大洲都是指數型變量，幸福等級是整數型變量，剩余變量都是數字型。

# Creating a new column for continents

Happiness$Continent <- NA

Happiness$Continent[which(Happiness$Country %in% c("Israel", "United Arab Emirates", "Singapore", "Thailand", "Taiwan Province of China",
"Qatar", "Saudi Arabia", "Kuwait", "Bahrain", "Malaysia", "Uzbekistan", "Japan",
"South Korea", "Turkmenistan", "Kazakhstan", "Turkey", "Hong Kong S.A.R., China", "Philippines",
"Jordan", "China", "Pakistan", "Indonesia", "Azerbaijan", "Lebanon", "Vietnam",
"Tajikistan", "Bhutan", "Kyrgyzstan", "Nepal", "Mongolia", "Palestinian Territories",
"Iran", "Bangladesh", "Myanmar", "Iraq", "Sri Lanka", "Armenia", "India", "Georgia",
"Cambodia", "Afghanistan", "Yemen", "Syria"))] <- "Asia"
Happiness$Continent[which(Happiness$Country %in% c("Norway", "Denmark", "Iceland", "Switzerland", "Finland",
"Netherlands", "Sweden", "Austria", "Ireland", "Germany",
"Belgium", "Luxembourg", "United Kingdom", "Czech Republic",
"Malta", "France", "Spain", "Slovakia", "Poland", "Italy",
"Russia", "Lithuania", "Latvia", "Moldova", "Romania",
"Slovenia", "North Cyprus", "Cyprus", "Estonia", "Belarus",
"Serbia", "Hungary", "Croatia", "Kosovo", "Montenegro",
"Greece", "Portugal", "Bosnia and Herzegovina", "Macedonia",
"Bulgaria", "Albania", "Ukraine"))] <- "Europe"
Happiness$Continent[which(Happiness$Country %in% c("Canada", "Costa Rica", "United States", "Mexico",
"Panama","Trinidad and Tobago", "El Salvador", "Belize", "Guatemala",
"Jamaica", "Nicaragua", "Dominican Republic", "Honduras",
"Haiti"))] <- "North America"
Happiness$Continent[which(Happiness$Country %in% c("Chile", "Brazil", "Argentina", "Uruguay",
"Colombia", "Ecuador", "Bolivia", "Peru",
"Paraguay", "Venezuela"))] <- "South America"
Happiness$Continent[which(Happiness$Country %in% c("New Zealand", "Australia"))] <- "Australia"
Happiness$Continent[which(is.na(Happiness$Continent))] <- "Africa"

# Moving the continent column's position in the dataset to the second column

Happiness <- Happiness %>% select(Country,Continent, everything())

# Changing Continent column to factor

Happiness$Continent <- as.factor(Happiness$Continent)

str(Happiness)

## 'data.frame': 155 obs. of 11 variables:
## $ Country : Factor w/ 155 levels "Afghanistan",..: 105 38 58 133 45 99 26 100 132 7 ...
## $ Continent : Factor w/ 6 levels "Africa","Asia",..: 4 4 4 4 4 4 5 3 4 3 ...
## $ Happiness.Rank : int 1 2 3 4 5 6 7 8 9 10 ...
## $ Happiness.Score : num 7.54 7.52 7.5 7.49 7.47 ...
## $ Economy : num 1.62 1.48 1.48 1.56 1.44 ...
## $ Family : num 1.53 1.55 1.61 1.52 1.54 ...
## $ Life.Expectancy : num 0.797 0.793 0.834 0.858 0.809 ...
## $ Freedom : num 0.635 0.626 0.627 0.62 0.618 ...
## $ Generosity : num 0.362 0.355 0.476 0.291 0.245 ...
## $ Trust : num 0.316 0.401 0.154 0.367 0.383 ...
## $ Dystopia.Residual: num 2.28 2.31 2.32 2.28 2.43 ...

可視化

在這一章節，我們將處理不同的變量來找出它們之間的相關性。

比較不同的洲的幸福變量

來計算一下平均幸福值和每個洲的其他七個因素的平均值。然后將不同的變量和對應的數值轉化到單獨的列中。最終，使用 ggplot 來表現不同大陸之間的差異性。

用 Kaggle 數據集來分析幸福指數

Happiness.Continent <- Happiness %>%
select(-3) %>%
group_by(Continent) %>%
summarise_at(vars(-Country), funs(mean(., na.rm=TRUE)))

# Or we can use aggregate
# aggregate(Happiness[, 4:11], list(Happiness$Continent), mean)

# Melting the "Happiness.Continent" dataset
Happiness.Continent.melt <- melt(Happiness.Continent)

# Faceting
ggplot(Happiness.Continent.melt, aes(y=value, x=Continent, color=Continent, fill=Continent)) +
geom_bar( stat="identity") +
facet_wrap(~variable) + theme_bw() +
theme(axis.text.x = element_text(angle = 90, hjust = 1)) +
labs(title = "Average value of happiness variables for different continents",
y = "Average value")

我們可以看到，澳大利亞在除反烏托邦殘余方面之外，幾乎所有的方面都達到最高的平均值，接著是歐洲，北美洲和南美洲幾乎相同的幸福平均值和剩余七方面的平均值。最后是，亞洲和非洲在所有方面都拿到了最低分。

每個洲的相關曲線

我們來看每個洲不同變量間的相關性。

corrgram(Happiness %>% select(-3) %>% filter(Continent == "Africa"), order=TRUE,
upper.panel=panel.cor, main="Happiness Matrix for Africa")

在非洲 “幸福值” 和其他變量的相關性：

經濟水平 > 家庭狀況 > 平均壽命> 反烏托邦殘留 > 自由度

幸福值與對政府的信任感之間沒有相關性。

幸福值和慷慨度之間呈反相關關系。

用 Kaggle 數據集來分析幸福指數

corrgram(Happiness %>% select(-3) %>% filter(Continent == "Asia"), order=TRUE,
upper.
=panel.cor, main="Happiness Matrix for Asia")

在亞洲 “幸福值” 和其他變量的相關性：

經濟水平 > 家庭狀況 > 平均壽命 > 自由度 > 對政府的信任感 > 反烏托邦殘留

幸福值和慷慨度之間沒有相關性。

corrgram(Happiness %>% select(-3) %>% filter(Continent == "Europe"), order=TRUE,
upper.panel=panel.cor, main="Happiness Matrix for Europe")

用 Kaggle 數據集來分析幸福指數

在歐洲 “幸福值” 和其他變量的相關性：

自由度 > 對政府的信任感 > 經濟水平 > 家庭狀況 > 反烏托邦殘留 > 平均壽命 > 慷慨度

歐洲出現了慷慨讀和幸福值之間最高的相關性。

corrgram(Happiness %>% select(-3) %>% filter(Continent == "North America"), order=TRUE,
upper.panel=panel.cor, main="Happiness Matrix for North America")

用 Kaggle 數據集來分析幸福指數

在北美洲的 “幸福值” 和其他變量的相關性：

平均壽命 > 經濟水平 > 自由度 > 家庭狀況 > 反烏托邦殘留 > 對政府的信任感

在這里幸福值和慷慨度呈現反相關關系。

用 Kaggle 數據集來分析幸福指數

corrgram(Happiness %>% select(-3) %>% filter(Continent == "South America"), order=TRUE,
upper.panel=panel.cor, main="Happiness Matrix for South America")

在南美洲的 “幸福值” 和其他變量的相關性：

反烏托邦殘留 > 經濟水平 > 平均壽命 > 自由度 > 慷慨度 > 對政府的信任感>家庭狀況

在南美洲，家庭狀況是最不重要的。

用 Kaggle 數據集來分析幸福指數

比較不同大洲的幸福值

我們將會使用散點圖，盒式圖和小提琴型圖來觀察幸福值在不同國家的分布，幸福值是如何填充在這些大洲的，并對每個大洲計算平均值和中位數。

用 Kaggle 數據集來分析幸福指數

####### Happiness score for each continent

gg1 <- ggplot(Happiness,
aes(x=Continent,
y=Happiness.Score,
color=Continent))+
geom_point() + theme_bw() +
theme(axis.title = element_text(family = "Helvetica", size = (8)))

gg2 <- ggplot(Happiness , aes(x = Continent, y = Happiness.Score)) +
geom_boxplot(aes(fill=Continent)) + theme_bw() +
theme(axis.title = element_text(family = "Helvetica", size = (8)))

gg3 <- ggplot(Happiness,aes(x=Continent,y=Happiness.Score))+
geom_violin(aes(fill=Continent),alpha=0.7)+ theme_bw() +
theme(axis.title = element_text(family = "Helvetica", size = (8)))

# Compute descriptive statistics by groups
stable <- desc_statby(Happiness, measure.var = "Happiness.Score",
grps = "Continent")
stable <- stable[, c("Continent","mean","median")]
names(stable) <- c("Continent", "Mean of happiness score","Median of happiness score")
# Summary table plot
stable.p <- ggtexttable(stable,rows = NULL,
theme = ttheme("classic"))

ggarrange(gg1, gg2, ncol = 1, nrow = 2)

ggarrange(gg3, stable.p, ncol = 1, nrow = 2)

正如我們所看到的那樣，澳大利亞的幸福值的中位數值最高。歐洲，南美洲，北美洲的中位數值并列第二。亞洲的數值最低，位于非洲以后。我們可以得到不同大洲的幸福值范圍，以及幸福值的集中程度。

帶有回歸線的散點圖

通過給不同大洲畫散點圖，我們可以確定幸福數據與數集中的其他七個因素之間的相關性。

用 Kaggle 數據集來分析幸福指數

ggplot(subset(Happiness, Happiness$Continent != "Australia"), aes(x = Life.Expectancy, y = Happiness.Score)) +
geom_point(aes(color=Continent), size = 3, alpha = 0.8) +
geom_smooth(aes(color = Continent, fill = Continent),
method = "lm", fullrange = TRUE) +
facet_wrap(~Continent) +
theme_bw() + labs(title = "Scatter plot with regression line")

平均壽命與幸福值的相關性在歐洲，北美洲和亞洲比其他洲更明顯。值得一提的是，澳大利亞的數據將不被計入結果，因為澳洲只有兩個國家，關于它作出的散點圖將不會有任何意義。

用 Kaggle 數據集來分析幸福指數

ggplot(subset(Happiness, Happiness$Continent != "Australia"), aes(x = Economy, y = Happiness.Score)) +
geom_point(aes(color=Continent), size = 3, alpha = 0.8) +
geom_smooth(aes(color = Continent, fill = Continent),
method = "lm", fullrange = TRUE) +
facet_wrap(~Continent) +
theme_bw() + labs(title = "Scatter plot with regression line")

關于幸福值與經濟水平的相關性，我們可以得到于前者很接近的結果。在這一個因素作用下，非洲的結果排在最末位。

用 Kaggle 數據集來分析幸福指數

ggplot(subset(Happiness, Happiness$Continent != "Australia"), aes(x = Freedom, y = Happiness.Score)) +
geom_point(aes(color=Continent), size = 3, alpha = 0.8) +
geom_smooth(aes(color = Continent, fill = Continent),
method = "lm", fullrange = TRUE) +
facet_wrap(~Continent) +
theme_bw() + labs(title = "Scatter plot with regression line")

自由度與幸福值的相關性，在歐洲和北美洲比其他任何洲都要顯著。

用 Kaggle 數據集來分析幸福指數

ggplot(subset(Happiness, Happiness$Continent != "Australia"), aes(x = Trust, y = Happiness.Score)) +
geom_point(aes(color=Continent), size = 3, alpha = 0.8) +
geom_smooth(aes(color = Continent, fill = Continent),
method = "lm", fullrange = TRUE) +
facet_wrap(~Continent) +
theme_bw() + labs(title = "Scatter plot with regression line")

在非洲，對政府的信任感和幸福值之間幾乎沒有相關性。

用 Kaggle 數據集來分析幸福指數

ggplot(subset(Happiness, Happiness$Continent != "Australia"), aes(x = Generosity, y = Happiness.Score)) +
geom_point(aes(color=Continent), size = 3, alpha = 0.8) +
geom_smooth(aes(color = Continent, fill = Continent),
method = "lm", fullrange = TRUE) +
facet_wrap(~Continent) +
theme_bw() + labs(title = "Scatter plot with regression line")

只有歐洲和南美洲對應的回歸線的斜率為正。亞洲的回歸線是水平的，非洲和北美洲對應的回歸線斜率為負。

用 Kaggle 數據集來分析幸福指數

ggplot(subset(Happiness, Happiness$Continent != "Australia"), aes(x = Family, y = Happiness.Score)) +
geom_point(aes(color=Continent), size = 3, alpha = 0.8) +
geom_smooth(aes(color = Continent, fill = Continent),
method = "lm", fullrange = TRUE) +
facet_wrap(~Continent) +
theme_bw() + labs(title = "Scatter plot with regression line")

對于南美洲而言，隨著家庭值增加，幸福值保持不變。

用 Kaggle 數據集來分析幸福指數

ggplot(subset(Happiness, Happiness$Continent != "Australia"), aes(x = Dystopia.Residual, y = Happiness.Score)) +
geom_point(aes(color=Continent), size = 3, alpha = 0.8) +
geom_smooth(aes(color = Continent, fill = Continent),
method = "lm", fullrange = TRUE) +
facet_wrap(~Continent) +
theme_bw() + labs(title = "Scatter plot with regression line")

針對反烏托邦殘留這項因素，所有大洲的表現近乎一致。

對不同大洲著色的散點圖

以下是觀察幸福值與不同變量的相關性，在不同大陸中分布的另一種方式。

用 Kaggle 數據集來分析幸福指數

#::::::::::::::::::::::::::::Family::::::::::::::::::::::::::::::
sp <- ggscatter(Happiness, x = "Family", y = "Happiness.Score",
color = "Continent", palette = "jco",
size = 3, alpha = 0.6)
# Create box plots of x/y variables
# Box plot of the x variable
xbp <- ggboxplot(Happiness$Family, width = 0.3, fill = "lightgray") +
rotate() +
theme_transparent()
# Box plot of the y variable
ybp <- ggboxplot(Happiness$Happiness.Score, width = 0.3, fill = "lightgray") +
theme_transparent()
# Create the external graphical objects
# called a "grop" in Grid terminology
xbp_grob <- ggplotGrob(xbp)
ybp_grob <- ggplotGrob(ybp)
# Place box plots inside the scatter plot
xmin <- min(Happiness$Family); xmax <- max(Happiness$Family)
ymin <- min(Happiness$Happiness.Score); ymax <- max(Happiness$Happiness.Score)
yoffset <- (1/15)*ymax; xoffset <- (1/15)*xmax
# Insert xbp_grob inside the scatter plot
sp + annotation_custom(grob = xbp_grob, xmin = xmin, xmax = xmax,
ymin = ymin-yoffset, ymax = ymin+yoffset) +
# Insert ybp_grob inside the scatter plot
annotation_custom(grob = ybp_grob,
xmin = xmin-xoffset, xmax = xmin+xoffset,
ymin = ymin, ymax = ymax)

用 Kaggle 數據集來分析幸福指數

#::::::::::::::::::::::::::::Generosity::::::::::::::::::::::::::::::
sp <- ggscatter(Happiness, x = "Generosity", y = "Happiness.Score",
color = "Continent", palette = "jco",
size = 3, alpha = 0.6)
# Create box plots of x/y variables
# Box plot of the x variable
xbp <- ggboxplot(Happiness$Generosity, width = 0.3, fill = "lightgray") +
rotate() +
theme_transparent()
# Box plot of the y variable
ybp <- ggboxplot(Happiness$Happiness.Score, width = 0.3, fill = "lightgray") +
theme_transparent()
# Create the external graphical objects
# called a "grop" in Grid terminology
xbp_grob <- ggplotGrob(xbp)
ybp_grob <- ggplotGrob(ybp)
# Place box plots inside the scatter plot
xmin <- min(Happiness$Generosity); xmax <- max(Happiness$Generosity)
ymin <- min(Happiness$Happiness.Score); ymax <- max(Happiness$Happiness.Score)
yoffset <- (1/15)*ymax; xoffset <- (1/15)*xmax
# Insert xbp_grob inside the scatter plot
sp + annotation_custom(grob = xbp_grob, xmin = xmin, xmax = xmax,
ymin = ymin-yoffset, ymax = ymin+yoffset) +
# Insert ybp_grob inside the scatter plot
annotation_custom(grob = ybp_grob,
xmin = xmin-xoffset, xmax = xmin+xoffset,
ymin = ymin, ymax = ymax)

用 Kaggle 數據集來分析幸福指數

#::::::::::::::::::::::::::::Life.Expectancy::::::::::::::::::::::::::::::
sp <- ggscatter(Happiness, x = "Life.Expectancy", y = "Happiness.Score",
color = "Continent", palette = "jco",
size = 3, alpha = 0.6)
# Create box plots of x/y variables
# Box plot of the x variable
xbp <- ggboxplot(Happiness$Life.Expectancy, width = 0.3, fill = "lightgray") +
rotate() +
theme_transparent()
# Box plot of the y variable
ybp <- ggboxplot(Happiness$Happiness.Score, width = 0.3, fill = "lightgray") +
theme_transparent()
# Create the external graphical objects
# called a "grop" in Grid terminology
xbp_grob <- ggplotGrob(xbp)
ybp_grob <- ggplotGrob(ybp)
# Place box plots inside the scatter plot
xmin <- min(Happiness$Life.Expectancy); xmax <- max(Happiness$Life.Expectancy)
ymin <- min(Happiness$Happiness.Score); ymax <- max(Happiness$Happiness.Score)
yoffset <- (1/15)*ymax; xoffset <- (1/15)*xmax
# Insert xbp_grob inside the scatter plot
sp + annotation_custom(grob = xbp_grob, xmin = xmin, xmax = xmax,
ymin = ymin-yoffset, ymax = ymin+yoffset) +
# Insert ybp_grob inside the scatter plot
annotation_custom(grob = ybp_grob,
xmin = xmin-xoffset, xmax = xmin+xoffset,
ymin = ymin, ymax = ymax)

用 Kaggle 數據集來分析幸福指數

#::::::::::::::::::::::::::::Freedom::::::::::::::::::::::::::::::
sp <- ggscatter(Happiness, x = "Freedom", y = "Happiness.Score",
color = "Continent", palette = "jco",
size = 3, alpha = 0.6)
# Create box plots of x/y variables
# Box plot of the x variable
xbp <- ggboxplot(Happiness$Freedom, width = 0.3, fill = "lightgray") +
rotate() +
theme_transparent()
# Box plot of the y variable
ybp <- ggboxplot(Happiness$Happiness.Score, width = 0.3, fill = "lightgray") +
theme_transparent()
# Create the external graphical objects
# called a "grop" in Grid terminology
xbp_grob <- ggplotGrob(xbp)
ybp_grob <- ggplotGrob(ybp)
# Place box plots inside the scatter plot
xmin <- min(Happiness$Freedom); xmax <- max(Happiness$Freedom)
ymin <- min(Happiness$Happiness.Score); ymax <- max(Happiness$Happiness.Score)
yoffset <- (1/15)*ymax; xoffset <- (1/15)*xmax
# Insert xbp_grob inside the scatter plot
sp + annotation_custom(grob = xbp_grob, xmin = xmin, xmax = xmax,
ymin = ymin-yoffset, ymax = ymin+yoffset) +
# Insert ybp_grob inside the scatter plot
annotation_custom(grob = ybp_grob,
xmin = xmin-xoffset, xmax = xmin+xoffset,
ymin = ymin, ymax = ymax)

用 Kaggle 數據集來分析幸福指數

#::::::::::::::::::::::::::::Economy::::::::::::::::::::::::::::::
sp <- ggscatter(Happiness, x = "Economy", y = "Happiness.Score",
color = "Continent", palette = "jco",
size = 3, alpha = 0.6)
# Create box plots of x/y variables
# Box plot of the x variable
xbp <- ggboxplot(Happiness$Economy, width = 0.3, fill = "lightgray") +
rotate() +
theme_transparent()
# Box plot of the y variable
ybp <- ggboxplot(Happiness$Happiness.Score, width = 0.3, fill = "lightgray") +
theme_transparent()
# Create the external graphical objects
# called a "grop" in Grid terminology
xbp_grob <- ggplotGrob(xbp)
ybp_grob <- ggplotGrob(ybp)
# Place box plots inside the scatter plot
xmin <- min(Happiness$Economy); xmax <- max(Happiness$Economy)
ymin <- min(Happiness$Happiness.Score); ymax <- max(Happiness$Happiness.Score)
yoffset <- (1/15)*ymax; xoffset <- (1/15)*xmax
# Insert xbp_grob inside the scatter plot
sp + annotation_custom(grob = xbp_grob, xmin = xmin, xmax = xmax,
ymin = ymin-yoffset, ymax = ymin+yoffset) +
# Insert ybp_grob inside the scatter plot
annotation_custom(grob = ybp_grob,
xmin = xmin-xoffset, xmax = xmin+xoffset,
ymin = ymin, ymax = ymax)

用 Kaggle 數據集來分析幸福指數

#::::::::::::::::::::::::::::Trust::::::::::::::::::::::::::::::
sp <- ggscatter(Happiness, x = "Trust", y = "Happiness.Score",
color = "Continent", palette = "jco",
size = 3, alpha = 0.6)
# Create box plots of x/y variables
# Box plot of the x variable
xbp <- ggboxplot(Happiness$Trust, width = 0.3, fill = "lightgray") +
rotate() +
theme_transparent()
# Box plot of the y variable
ybp <- ggboxplot(Happiness$Happiness.Score, width = 0.3, fill = "lightgray") +
theme_transparent()
# Create the external graphical objects
# called a "grop" in Grid terminology
xbp_grob <- ggplotGrob(xbp)
ybp_grob <- ggplotGrob(ybp)
# Place box plots inside the scatter plot
xmin <- min(Happiness$Trust); xmax <- max(Happiness$Trust)
ymin <- min(Happiness$Happiness.Score); ymax <- max(Happiness$Happiness.Score)
yoffset <- (1/15)*ymax; xoffset <- (1/15)*xmax
# Insert xbp_grob inside the scatter plot
sp + annotation_custom(grob = xbp_grob, xmin = xmin, xmax = xmax,
ymin = ymin-yoffset, ymax = ymin+yoffset) +
# Insert ybp_grob inside the scatter plot
annotation_custom(grob = ybp_grob,
xmin = xmin-xoffset, xmax = xmin+xoffset,
ymin = ymin, ymax = ymax)

用 Kaggle 數據集來分析幸福指數

#::::::::::::::::::::::::::::Dystopia.Residual::::::::::::::::::::::::::::::
sp <- ggscatter(Happiness, x = "Dystopia.Residual", y = "Happiness.Score",
color = "Continent", palette = "jco",
size = 3, alpha = 0.6)
# Create box plots of x/y variables
# Box plot of the x variable
xbp <- ggboxplot(Happiness$Dystopia.Residual, width = 0.3, fill = "lightgray") +
rotate() +
theme_transparent()
# Box plot of the y variable
ybp <- ggboxplot(Happiness$Happiness.Score, width = 0.3, fill = "lightgray") +
theme_transparent()
# Create the external graphical objects
# called a "grop" in Grid terminology
xbp_grob <- ggplotGrob(xbp)
ybp_grob <- ggplotGrob(ybp)
# Place box plots inside the scatter plot
xmin <- min(Happiness$Dystopia.Residual); xmax <- max(Happiness$Dystopia.Residual)
ymin <- min(Happiness$Happiness.Score); ymax <- max(Happiness$Happiness.Score)
yoffset <- (1/15)*ymax; xoffset <- (1/15)*xmax
# Insert xbp_grob inside the scatter plot
sp + annotation_custom(grob = xbp_grob, xmin = xmin, xmax = xmax,
ymin = ymin-yoffset, ymax = ymin+yoffset) +
# Insert ybp_grob inside the scatter plot
annotation_custom(grob = ybp_grob,
xmin = xmin-xoffset, xmax = xmin+xoffset,
ymin = ymin, ymax = ymax)

三維圖

在可視化的最后一部分，讓我們作一些特別的圖。我必須聲明，我并不支持三維圖或任何特別的圖，不過我們可以通過它們增加一些趣味性！

用 Kaggle 數據集來分析幸福指數

scatter3D(Happiness$Freedom, Happiness$Life.Expectancy, Happiness$Happiness.Score, phi = 0, bty = "g",
pch = 20, cex = 2, ticktype = "detailed",
main = "Happiness data", xlab = "Freedom",
ylab ="Life.Expectancy", zlab = "Happiness.Score")

根據這個圖可以得知，平均壽命越高，自由度越強，幸福值就會越高。

用 Kaggle 數據集來分析幸福指數

scatter3D(Happiness$Generosity, Happiness$Economy, Happiness$Happiness.Score, phi = 0, bty = "g",
pch = 20, cex = 2, ticktype = "detailed",
main = "Happiness data", xlab = "Generosity",
ylab ="Economy", zlab = "Happiness.Score")

經濟水平越高，慷慨度越低，會導致更高的幸福水平。

用 Kaggle 數據集來分析幸福指數

scatter3D(Happiness$Trust, Happiness$Freedom, Happiness$Happiness.Score, phi = 0, bty = "g",
pch = 20, cex = 2, ticktype = "detailed",
main = "Happiness data", xlab = "Trust",
ylab ="Freedom", zlab = "Happiness.Score")

總體而言，對政府的信任感對于取得更高的幸福值并不會起到關鍵作用。不過我們可以看到，對于那些自由度很重要并且幸福值超過 7 分的國家來說，信任感很重要。

用 Kaggle 數據集來分析幸福指數

scatter3D(Happiness$Family, Happiness$Economy, Happiness$Happiness.Score, phi = 0, bty = "g",
pch = 20, cex = 2, ticktype = "detailed",
main = "Happiness data", xlab = "Trust",
ylab ="Economy", zlab = "Happiness.Score")

對于那些幸福值低于 5 分的國家通過相關性曲線可以看出，隨著經濟水平的提高和幸福值的增加，信任感保持不變。而在幸福值 5 分這一點之后，信任感對幸福值增加的影響逐漸增大。

預測

在這一章，我們將運用不同的機器學習算法來預測幸福值。首先，我們需要將數集分成訓練組和測試組。我們的因變量是幸福值，自變量分別是家庭狀況，經濟水平，信任感，自由度，慷慨度和反烏托邦殘留。

# Splitting the dataset into the Training set and Test set
# install.packages('caTools')
library(caTools)
set.seed(123)
dataset <- Happiness[4:11]
split = sample.split(dataset$Happiness.Score, SplitRatio = 0.8)
training_set = subset(dataset, split == TRUE)
test_set = subset(dataset, split == FALSE)

多元線性回歸

# Fitting Multiple Linear Regression to the Training set
regressor_lm = lm(formula = Happiness.Score ~ .,
data = training_set)

summary(regressor_lm)

##
## Call:
## lm(formula = Happiness.Score ~ ., data = training_set)
##
## Residuals:
## Min 1Q Median 3Q Max
## -5.907e-04 -2.008e-04 -1.600e-07 2.510e-04 4.855e-04
##
## Coefficients:
## Estimate Std. Error t value Pr(>|t|)
## (Intercept) 1.701e-04 1.509e-04 1.127 0.262
## Economy 1.000e+00 1.300e-04 7690.839 <2e-16 ***
## Family 9.999e-01 1.253e-04 7981.804 <2e-16 ***
## Life.Expectancy 9.997e-01 2.122e-04 4711.655 <2e-16 ***
## Freedom 9.999e-01 2.245e-04 4453.253 <2e-16 ***
## Generosity 1.000e+00 2.310e-04 4330.040 <2e-16 ***
## Trust 9.997e-01 3.335e-04 2997.191 <2e-16 ***
## Dystopia.Residual 1.000e+00 5.452e-05 18343.021 <2e-16 ***
## ---
## Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
##
## Residual standard error: 0.0002848 on 116 degrees of freedom
## Multiple R-squared: 1, Adjusted R-squared: 1
## F-statistic: 2.689e+08 on 7 and 116 DF, p-value: < 2.2e-16

結果表明，所有的自變量都有重要的作用且校準的 R 的平方為 1！就如我們探討的那樣，自變量與因變量之間存在明顯的線性關系。同樣，我要強調自變量之和等于因變量，也就是幸福值。這就證明了校準的 R 的平方為 1 這個結論。因此，推測多元線性回歸將可以 100% 正確的預測幸福值。

####### Predicting the Test set results
y_pred_lm = predict(regressor_lm, newdata = test_set)

Pred_Actual_lm <- as.data.frame(cbind(Prediction = y_pred_lm, Actual = test_set$Happiness.Score))

gg.lm <- ggplot(Pred_Actual_lm, aes(Actual, Prediction )) +
geom_point() + theme_bw() + geom_abline() +
labs(title = "Multiple Linear Regression", x = "Actual happiness score",
y = "Predicted happiness score") +
theme(plot.title = element_text(family = "Helvetica", face = "bold", size = (15)),
axis.title = element_text(family = "Helvetica", size = (10)))
gg.lm

用 Kaggle 數據集來分析幸福指數

和預期一樣，實際和預測的對比圖證明了模型的準確性。

SVR（支持向量回歸）

用 Kaggle 數據集來分析幸福指數

# Fitting SVR to the dataset
library(e1071)
regressor_svr = svm(formula = Happiness.Score ~ .,
data = dataset,
type = 'eps-regression',
kernel = 'radial')

# Predicting a new result
y_pred_svr = predict(regressor_svr, newdata = test_set)

Pred_Actual_svr <- as.data.frame(cbind(Prediction = y_pred_svr, Actual = test_set$Happiness.Score))

Pred_Actual_lm.versus.svr <- cbind(Prediction.lm = y_pred_lm, Prediction.svr = y_pred_svr, Actual = test_set$Happiness.Score)

gg.svr <- ggplot(Pred_Actual_svr, aes(Actual, Prediction )) +
geom_point() + theme_bw() + geom_abline() +
labs(title = "SVR", x = "Actual happiness score",
y = "Predicted happiness score") +
theme(plot.title = element_text(family = "Helvetica", face = "bold", size = (15)),
axis.title = element_text(family = "Helvetica", size = (10)))
gg.svr

通過支持向量回歸預測出的幸福值具有相當高的準確性。

決策樹回歸

# Fitting Decision Tree Regression to the dataset
library(rpart)
regressor_dt = rpart(formula = Happiness.Score ~ .,
data = dataset,
control = rpart.control(minsplit = 10))

# Predicting a new result with Decision Tree Regression
y_pred_dt = predict(regressor_dt, newdata = test_set)

Pred_Actual_dt <- as.data.frame(cbind(Prediction = y_pred_dt, Actual = test_set$Happiness.Score))

gg.dt <- ggplot(Pred_Actual_dt, aes(Actual, Prediction )) +
geom_point() + theme_bw() + geom_abline() +
labs(title = "Decision Tree Regression", x = "Actual happiness score",
y = "Predicted happiness score") +
theme(plot.title = element_text(family = "Helvetica", face = "bold", size = (15)),
axis.title = element_text(family = "Helvetica", size = (10)))
gg.dt

用 Kaggle 數據集來分析幸福指數

看起來對于這個數集，決策樹回歸不是一個好的選擇。我們來看看這個樹狀圖。

用 Kaggle 數據集來分析幸福指數

# Plotting the tree
library(rpart.plot)
prp(regressor_dt)

隨機森林回歸

用 Kaggle 數據集來分析幸福指數

# Fitting Random Forest Regression to the dataset
library(randomForest)
set.seed(1234)
regressor_rf = randomForest(x = dataset[-1],
y = dataset$Happiness.Score,
ntree = 500)

# Predicting a new result with Random Forest Regression
y_pred_rf = predict(regressor_rf, newdata = test_set)

Pred_Actual_rf <- as.data.frame(cbind(Prediction = y_pred_rf, Actual = test_set$Happiness.Score))

gg.rf <- ggplot(Pred_Actual_rf, aes(Actual, Prediction )) +
geom_point() + theme_bw() + geom_abline() +
labs(title = "Random Forest Regression", x = "Actual happiness score",
y = "Predicted happiness score") +
theme(plot.title = element_text(family = "Helvetica", face = "bold", size = (15)),
axis.title = element_text(family = "Helvetica", size = (10)))
gg.rf

隨機森林回歸得到的結果沒有支持向量回歸那么好，不過比決策樹回歸要好的多。

神經網絡

用 Kaggle 數據集來分析幸福指數

# Fitting Neural Net to the training set
library(neuralnet)

nn <- neuralnet(Happiness.Score ~ Economy + Family + Life.Expectancy + Freedom + Generosity + Trust + Dystopia.Residual,
data=training_set,hidden=10,linear.output=TRUE)
plot(nn)

predicted.nn.values <- compute(nn,test_set[,2:8])

Pred_Actual_nn <- as.data.frame(cbind(Prediction = predicted.nn.values$net.result, Actual = test_set$Happiness.Score))

gg.nn <- ggplot(Pred_Actual_nn, aes(Actual, V1 )) +
geom_point() + theme_bw() + geom_abline() +
labs(title = "Neural Net", x = "Actual happiness score",
y = "Predicted happiness score") +
theme(plot.title = element_text(family = "Helvetica", face = "bold", size = (15)),
axis.title = element_text(family = "Helvetica", size = (10)))
gg.nn

神經網絡是僅次于多元線性回歸的最好的預測算法。事實上，通過神經網絡模型預測幸福值，其準確性接近 100% 。我們對多元線性回歸和神經網絡模型計算均方差。

MSE.lm <- sum((test_set$Happiness.Score - y_pred_lm)^2)/nrow(test_set)
MSE.nn <- sum((test_set$Happiness.Score - predicted.nn.values$net.result)^2)/nrow(test_set)

print(paste("Mean Squared Error (Multiple Linear Regression):", MSE.lm))