Question

Data set “quine” from MASS package children from an Australian town is classified by ethnic background, gender, age, learning status and the number of days absent from school. The columns “Eth” indicates whether the student is Aboriginal or not (“A” or “N”), and the column Sex indicates Male or Female (“M” or “F”).

a) Print the first five observations of the data.

b) Is the proportion of aboriginal female different from that of male?

Use R to solve and show R code

Answer 1

Load the library MASS.use dim statement to view columns and observations.

with print statement print the observations

To view the column names use names statement

Rcode is:

library(MASS)
dim(quine)
names(quine)
print(quine)

head(quine)

Ou Eth Sex Age Lrn Days
1 A M F0 SL 2
2 A M F0 SL 11
3 A M F0 SL 14
4 A M F0 AL 5
5 A M F0 AL 5
6 A M F0 AL 13

Solutionb;

b) Is the proportion of aboriginal female different from that of male?

use below R code:

prop.test(table(quine$Eth,quine$Sex))

Output:

2-sample test for equality of proportions with continuity correction

data: table(quine$Eth, quine$Sex)

X-squared = 2.606e-30, df = 1, p-value = 1

alternative hypothesis: two.sided

95 percent confidence interval:

-0.1616919 0.1722321

sample estimates:

prop 1 prop 2

0.5507246 0.5454545

p=1

there is no sufficient statistical evidence at 5% level of significance to conclude that  proportion of aboriginal female different from that of male

that is  proportion of aboriginal femaleis not different from that of male.