```r
install.packages("https://cran.rstudio.com/bin/windows/contrib/4.1/faraway_1.0.7.zip", repos = NULL)
## 將程式套件安載入 'C:/Users/user/Documents/R/win-library/4.1'
## (因為 'lib' 沒有被指定)
## package 'faraway' successfully unpacked and MD5 sums checked
library("faraway")
## Warning: 套件 'faraway' 是用 R 版本 4.1.2 來建造的
data('hsb')
summary(hsb)
##        id            gender              race         ses         schtyp   
##  Min.   :  1.00   female:109   african-amer: 20   high  :58   private: 32  
##  1st Qu.: 50.75   male  : 91   asian       : 11   low   :47   public :168  
##  Median :100.50                hispanic    : 24   middle:95                
##  Mean   :100.50                white       :145                            
##  3rd Qu.:150.25                                                            
##  Max.   :200.00                                                            
##        prog          read           write            math          science     
##  academic:105   Min.   :28.00   Min.   :31.00   Min.   :33.00   Min.   :26.00  
##  general : 45   1st Qu.:44.00   1st Qu.:45.75   1st Qu.:45.00   1st Qu.:44.00  
##  vocation: 50   Median :50.00   Median :54.00   Median :52.00   Median :53.00  
##                 Mean   :52.23   Mean   :52.77   Mean   :52.65   Mean   :51.85  
##                 3rd Qu.:60.00   3rd Qu.:60.00   3rd Qu.:59.00   3rd Qu.:58.00  
##                 Max.   :76.00   Max.   :67.00   Max.   :75.00   Max.   :74.00  
##      socst      
##  Min.   :26.00  
##  1st Qu.:46.00  
##  Median :52.00  
##  Mean   :52.41  
##  3rd Qu.:61.00  
##  Max.   :71.00

```r
library(e1071)
## Warning: 套件 'e1071' 是用 R 版本 4.1.2 來建造的
library(moments)
## Warning: 套件 'moments' 是用 R 版本 4.1.1 來建造的
## 
## 載入套件:'moments'
## 下列物件被遮斷自 'package:e1071':
## 
##     kurtosis, moment, skewness
aggregate(cbind(read, write, math, science, socst) ~ gender, data = hsb, mean)
##   gender     read    write     math  science    socst
## 1 female 51.73394 54.99083 52.39450 50.69725 52.91743
## 2   male 52.82418 50.12088 52.94505 53.23077 51.79121
aggregate(cbind(read, write, math, science, socst) ~ gender, data = hsb, sd)
##   gender     read     write     math   science    socst
## 1 female 10.05783  8.133715 9.151015  9.038503 10.23441
## 2   male 10.50671 10.305161 9.664784 10.732171 11.33384
aggregate(cbind(read, write, math, science, socst) ~ gender, data = hsb, skewness)
##   gender       read      write      math   science      socst
## 1 female 0.32341745 -0.5899993 0.2346739 -0.130718 -0.3532812
## 2   male 0.04674873 -0.1798980 0.3256960 -0.345221 -0.3713532
aggregate(cbind(read, write, math, science, socst) ~ gender, data = hsb, kurtosis)
##   gender     read    write     math  science    socst
## 1 female 2.500028 2.544105 2.284784 2.510875 2.519207
## 2   male 2.262737 1.872877 2.356806 2.371868 2.335229
aggregate(cbind(read, write, math, science, socst) ~ race, data = hsb, mean)
##           race     read    write     math  science    socst
## 1 african-amer 46.80000 48.20000 46.75000 42.80000 49.45000
## 2        asian 51.90909 58.00000 57.27273 51.45455 51.00000
## 3     hispanic 46.66667 46.45833 47.41667 45.37500 47.79167
## 4        white 53.92414 54.05517 53.97241 54.20000 53.68276
aggregate(cbind(read, write, math, science, socst) ~ race, data = hsb, sd)
##           race      read    write      math  science     socst
## 1 african-amer  7.120024 9.322299  6.487843 9.445690 10.850540
## 2        asian  7.660999 7.899367 10.120187 9.490665  9.746794
## 3     hispanic 10.239169 8.272422  6.983936 8.218815  9.250049
## 4        white 10.276783 9.172558  9.383011 9.094870 10.813253
aggregate(cbind(read, write, math, science, socst) ~ race, data = hsb, skewness)
##           race        read      write       math    science      socst
## 1 african-amer  0.56341685  0.2445555  1.5769616  0.1618054 -0.3779222
## 2        asian -0.14903573 -0.8732263 -0.2921502 -0.3239360  0.3398069
## 3     hispanic  0.64286691  0.3420989  0.1538455  0.2121507  0.1741367
## 4        white  0.05686143 -0.7452076  0.1120681 -0.2394562 -0.5568882
aggregate(cbind(read, write, math, science, socst) ~ race, data = hsb, kurtosis)
##           race     read    write     math  science    socst
## 1 african-amer 4.394131 2.069851 5.739716 1.833490 2.553280
## 2        asian 2.457166 2.518799 1.843283 2.240411 2.849030
## 3     hispanic 3.381917 2.777992 2.494265 3.361737 2.218556
## 4        white 2.203770 2.710911 2.351510 2.506333 2.641000
my_summary <- function(x) {
 require(moments)
 funs <- c(mean, sd, skewness, kurtosis)
 sapply(funs, function(f) f(x, na.rm = TRUE))
}
sapply(hsb[, c(7:11)], my_summary)
##            read      write       math    science      socst
## [1,] 52.2300000 52.7750000 52.6450000 51.8500000 52.4050000
## [2,] 10.2529368  9.4785860  9.3684478  9.9008908 10.7357935
## [3,]  0.1948373 -0.4784158  0.2844115 -0.1872277 -0.3786624
## [4,]  2.3630520  2.2385271  2.3373193  2.4283076  2.4585395