Homework 1, Due F 01/19
Read Chapter 1 (Moore).
Read the section on Assignment Format, Page 2 from
http://math.arizona.edu/ abhishek/math160/policy.pdf .
Problems
1. Look at the data set attached with the homework. Download it.
a) What is the population that we are studying through this data set? What
individuals does it describe?
b) Apart from SNO, how many variables does the data set contain? Which
of them are categorical and which are quantitative?
c) Make a table showing showing the sex counts. The table should have
three columns, namely Sex,Count and Percent count. Draw a pie chart to
display the data. Mark clearly the angles in the chart. What do you see?
d) Divide your Majors into few important categories, one of them being
Others. Make a table showing the different categories, total number of stu-
dents, number of female and male students in each category. Make a bar graph
of the total counts with bars in order from tallest to shortest. What is the
most popular subject among the students? Is it significantly apart from other
subjects?
e) Make a table showing the percent of females and males in each Major
category from part (d). Make two separate bar graphs for females and males
respectively. What are the similarities and differences between the graphs?
f) Divide the ages of the students into classes of equal length namely, 17.0โ
18.9, 19.0โ20.9, 21.0โ22.9, 23.0โ24.9 and 25.0โ26.9 and display the number
of students in each class. Make a histogram to plot the data. Describe the
shape of the histogram. Is it symmetric, skewed to the left/right or none? Does
it have a single peak? Are there any outliers? What is the average age of the
students?
g) Draw a stemplot to display the date of birth. The stems are the year of
birth which are 82,83,...,88 and the leaves are the months which take values:
01,02,...,11,12. Describe the shape, center and peaks of the distribution. Are
the results consistent with that of part (f)? Why/Why not?
h) Make a back to back stemplot to compare the female and male date
of births. That is, use one set of stems (year of birth) with two sets of leaves
(months), one to the right and one to the left of the stems. (Draw a line on
either side of the stems to separate stems and leaves). Does it appear that girls
are older than boys?
2. Ex 1.32, Page 30 (Moore).
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