Question

2.2 Graphical Methods for Describing Quantitative Data 1. Consider the stem-and-leaf display below, leaf unit 0.1. Stem Leaf 0 012 2 3 00036 2248 2 1134599 4 457 5 13 How many observations in the data set? How do you decide? a) b) Re-create all numbers, order them in descending order. c) Construct a dot plot.

Answer 1

a) Observations in the data set =24

In the Stem-and-leaf plot total number of observation is equal to the number of leafs. Count the leaf in all stem you will gate observation in the data set.

b) All numbers:

0.0, 0.1, 0.2, 1.2, 1.2, 1.4, 1.8, 2.1, 2.1, 2.3, 2.4, 2.5, 2.9, 2.9, 3.0, 3.0, 3.0, 3.3, 3.6, 4.4, 4.5, 4.7, 5.1, 5.3

Numbers in descending order:

5.3, 5.1, 4.7, 4.5, 4.4, 3.6, 3.3, 3.0, 3.0, 3.0, 2.9, 2.9, 2.5, 2.4, 2.3, 2.1, 2.1, 1.8, 1.4, 1.2, 1.2, 0.2, 0.1, 0.0

C) Dot plot

8 5.0 6.0 0 1.0 2.0 3.0 4.0 data