Creating a Line Graph (or XY Graph)
Line graphs , or XY graphs, are used to visually display data (the results
of an experiment) in such a way as to show the relationship of one factor,
such as disease severity, to another factor, such as time. For a line
graph, both factors need to be quantitative in nature, meaning that they
can be expressed as a numerical value, such as temperature or time. Qualitative
(or catagorical) factors, such as kinds of trees or eye color, can
not be a component of a line graph. A line graph is set up as a vertical
axis (the Y axis) and a horizontal axis (the X axis), forming a grid.
One of the two factors is measured on the Y axis and the other is measured
on the X axis. To create the graph a point is placed on the grid where
the value of the X variable and the value of theY variable intersect. A
line is then drawn to connect the points on the graph, moving from left
to right.
