Section 2.1
9
69%
55.2 million
inferential because it’s making a conclusion based on observed data
11
.42; .61
55+
18-34
the older you are the more likely you are to buy products made in America
13
datt <- c(125, 324, 552, 1257, 2518)
rel.freqq <- datt/sum(datt)
categoriess <- c("Never", "Rarely", "Sometimes", "Most of time", "Always")
answerr <- data.frame(categoriess,rel.freqq)
answerr
## categoriess rel.freqq
## 1 Never 0.02617253
## 2 Rarely 0.06783920
## 3 Sometimes 0.11557789
## 4 Most of time 0.26319095
## 5 Always 0.52721943
52.721%
9.4%
barplot(datt,main=“Seat Belt Usage”,names=categoriess, col =c(“red”,“blue”,“green”,“yellow”,“orange”))
barplot(datt,main="Seat Belt Usage",names=categoriess, col =c("red","blue","green","yellow","orange"))
barplot(rel.freqq,main="Seat Belt Usage",names=categoriess, col =c("red","blue","green","yellow","orange"))
pie(datt,main="Seat Belt Usage",labels=categoriess, col =c("red","blue","green","yellow","orange"))
15
dat <- c(377,192,132,81,243)
rel.freq <- dat/sum(dat)
categories <- c("More 1", "Up to 1", "Few a week", "Few a month", "Never")
answer <- data.frame(categories,rel.freq)
answer
## categories rel.freq
## 1 More 1 0.36780488
## 2 Up to 1 0.18731707
## 3 Few a week 0.12878049
## 4 Few a month 0.07902439
## 5 Never 0.23707317
24%
barplot(dat,main=“Internet Usage”,names=categories, col =c(“red”,“blue”,“green”,“yellow”,“orange”))
barplot(dat,main="Internet Usage",names=categories, col =c("red","blue","green","yellow","orange"))
barplot(rel.freq,main="Internet Usage(Relative Freq)",names=categories, col =c("red","blue","green","yellow","orange"))
pie(dat,main="Internet Usage",labels=categories, col =c("red","blue","green","yellow","orange"))
Section 2.2
9
8
2
15
4
15%
bell-shape
10
4
9
17%
skewed right
11
200
10
60-69: 2, 70-79: 3, 80-89: 13, 90-99: 42, 100-109: 58, 110-119: 40, 120-129: 31, 130-139: 8, 140-149: 2, 150-159: 1
100-109
150-159
5.5%
no
12
200
0-199, 200-399, 400-599, 600-799, 800-999, 1000-1199, 1200-1399
0-199
skewed right
There are too many lurking variables and also Texas is much larger (and has more people) than Vermont.
13
skewed right - lower and middle classes are larger than the higher class
bell-shaped - students will evenly fall below or above the average
skewed right - people are single and live with smaller number of people more often
skewed left - typically older people affected
14
skewed right - most people don’t drink too much
uniform - classes are typically similar in size
skewed left - typically older people affected
bell-shape - men will evenly fall below or above the average
15
dattt <- c(16, 18, 12, 3, 1)
rel.freqqq <- dattt/sum(dattt)
categoriesss <- c("Zero", "One", "Two", "Three", "Four")
answerrr <- data.frame(categoriesss,rel.freqqq)
answerrr
## categoriesss rel.freqqq
## 1 Zero 0.32
## 2 One 0.36
## 3 Two 0.24
## 4 Three 0.06
## 5 Four 0.02
24%
60%