Table of survived coloumn created of titanic dataset
The table is a way row table
table(titanic.df$Survived)
##
## 0 1
## 549 340
addmargins(table(titanic.df$Survived))
##
## 0 1 Sum
## 549 340 889
addmargins(prop.table(table(titanic.df$Survived)))*100
##
## 0 1 Sum
## 61.75478 38.24522 100.00000
Thus here we have got Total passengers aboard, Total passengers who survived and percentage of total passengers who survived
mytable <- xtabs(~ Survived + Pclass, data=titanic.df)
mytable
## Pclass
## Survived 1 2 3
## 0 80 97 372
## 1 134 87 119
addmargins(prop.table(mytable, 2))*100
## Pclass
## Survived 1 2 3 Sum
## 0 37.38318 52.71739 75.76375 165.86432
## 1 62.61682 47.28261 24.23625 134.13568
## Sum 100.00000 100.00000 100.00000 300.00000
Thus we have got the total number of survived first class passengers and percentage of first class passengers who survived sinking
mytable <- xtabs(~Survived + Pclass + Sex, data = titanic.df)
mytable
## , , Sex = female
##
## Pclass
## Survived 1 2 3
## 0 3 6 72
## 1 89 70 72
##
## , , Sex = male
##
## Pclass
## Survived 1 2 3
## 0 77 91 300
## 1 45 17 47
Thus we have the number of female passengers from 1st class who survived
mytable <- xtabs(~ Survived + Sex, data = titanic.df)
addmargins(prop.table(mytable, 1), 2)*100
## Sex
## Survived female male Sum
## 0 14.75410 85.24590 100.00000
## 1 67.94118 32.05882 100.00000
addmargins(prop.table(mytable, 2), 1)*100
## Sex
## Survived female male
## 0 25.96154 81.10919
## 1 74.03846 18.89081
## Sum 100.00000 100.00000
Thus we have the percent of survivors who were female and the percentage of female who survived
mytable <- xtabs(~ Survived + Sex, data = titanic.df)
mytable
## Sex
## Survived female male
## 0 81 468
## 1 231 109
addmargins(mytable)
## Sex
## Survived female male Sum
## 0 81 468 549
## 1 231 109 340
## Sum 312 577 889
chisq.test(mytable)
##
## Pearson's Chi-squared test with Yates' continuity correction
##
## data: mytable
## X-squared = 258.43, df = 1, p-value < 2.2e-16
If p-value < 0.01, then we can safely reject the null hypothesis that sex of passenger and survival is Dependent.