統計期中

we <- c(68,85,74,88,63,78,90,80,58,63)

we2 <- c(85,91,74,100,82,84,78,100,51,70)

mean(we)      #平均數

## [1] 74.7

plot(we,we2,
     pch = 17,
     col= "skyblue",
     main ="班上的統計與數學",
     xlab ="統計",
     ylab ="數學")

we <- c(85,91,74,100,82,84,78,100,51,70)
hist(we,
     col= "purple",
     main ="班上數學成績",
     xlab ="數學",
     ylab ="frequency")

value <- c(185,82,36,28,25)
name <- c("娛樂休閒","知識閱讀","體育競技","科學創新","公益活動")
library(ggplot2)
# Load ggplot2
library(ggplot2)

# Create data
data <- data.frame(
  name=c("娛樂休閒","知識閱讀","體育競技","科學創新","公益活動") ,  
  value=c(185,82,36,28,25)
  )

# Barplot
ggplot(data, aes(x=name, y=value)) + 
  geom_bar(stat = "identity", width=0.2,  fill="yellow")

data<- c(185,82,36,28,25)
labels <- c("娛樂休閒","知識閱讀","體育競技","科學創新","公益活動")

pie(data,labels,main ="學生的比例", col=heat.colors(length(data)))

club_type <- c("娛樂休閒", "知識閱讀", "體育競技", "科學創新", "公益活動")
frequency <- c(185, 82, 36, 28, 25)

# 棒棒糖圖
plot(frequency,
     type = "n",  # 不先畫點
     xaxt = "n",  # 不畫 x 軸
     main = "大學生最喜歡參加的社團類型",
     xlab = "社團類型",
     ylab = "次數",
     ylim = c(0, max(frequency) + 20))

# 畫棒棒糖的線（棒子）
segments(x0 = 1:5, y0 = 0, x1 = 1:5, y1 = frequency, col = "skyblue", lwd = 2)

# 畫棒棒糖的頭（糖果球）
points(1:5, frequency, pch = 16, col = "orange", cex = 2)

# 加上 X 軸標籤
axis(1, at = 1:5, labels = club_type)

data <- read.csv("C:/Users/wenzao/Downloads/table1_1.csv")


if ("Japanese" %in% colnames(data)) {

  stem(data$Japanese)
} else {
  print("找不到 Japanese 欄位，請確認檔案內容是否正確。")
}

## 
##   The decimal point is 1 digit(s) to the right of the |
## 
##   4 | 9
##   5 | 139
##   6 | 13
##   7 | 9
##   8 | 49
##   9 | 1

data <- read.csv("C:/Users/wenzao/Downloads/table1_1.csv")

names(data)  # 確保有 "Japanese" 欄位

## [1] "Name"       "Statistic"  "Math"       "Japanese"   "Management"
## [6] "Accounting"

japanese <- data$Japanese


mean_jp <- mean(japanese)

# 中位數
median_jp <- median(japanese)


get_mode <- function(x) {
  uniq_vals <- unique(x)
  uniq_vals[which.max(tabulate(match(x, uniq_vals)))]
}
mode_jp <- get_mode(japanese)


sd_jp <- sd(japanese)


var_jp <- var(japanese)


q1_jp <- quantile(japanese, 0.25)


q3_jp <- quantile(japanese, 0.75)


result <- data.frame(
  統計量 = c("平均數", "中位數", "眾數", "標準差", "變異數", "第一四分位數", "第三四分位數"),
  數值 = c(mean_jp, median_jp, mode_jp, sd_jp, var_jp, q1_jp, q3_jp)
)

print(result)

##         統計量      數值
## 1       平均數  67.90000
## 2       中位數  62.00000
## 3         眾數  84.00000
## 4       標準差  16.25115
## 5       變異數 264.10000
## 6 第一四分位數  54.50000
## 7 第三四分位數  82.75000