Line Graphs
Prerequisites
Bar
Charts
Learning Objectives
 Create and interpret line graphs
 Judge a line graph would be a appropriate for a given dataset
A line graph is a bar chart
with the tops of the bars represented by points joined by lines
(the rest of the bar is suppressed).
Line graphs are appropriate only when both the X
and Yaxes display ordered (rather than qualitative) variables.
Although bar graphs can also be used in this situation, line
graphs are generally better at comparing changes over time. Let
us stress that it is misleading to use a line graph when the
Xaxis contains merely qualitative variables.
