You will represent some of the important events in the world by using bar graphs.
After completing this tutorial, you will be able to complete the following:
A bar graph is a visual representation of a set of data.
A bar graph is a graph that compares different amounts using bars. Each rectangular bar represents the value of a specific group or category. Bar graphs are typically used when comparing categorical data. Categorical data is data that can be placed into categories that are mutually exclusive.
In this example taken from the Activity Object, the bar graph represents the number of tornadoes in the U.S. for each year from 1998 - 2003. The data for Year is the categorical data because each year is a category that stands alone. The bars show the number of tornadoes occurring in a specific year.
Though you can extract trends between bars (e.g., they are gradually getting longer or shorter), you cannot determine changes over time or determine a slope. Each bar in the graph is independent from one another.
Bar graphs are created using the x and y axes on a coordinate grid.
The x-axis and y-axis are two lines that create the coordinate plane. The
x-axis is a horizontal line and the y-axis is a vertical line.
In the above bar graph, the x-axis represents the year. This is the categorical data. Because the categorical data appears on the x-axis this is a vertical bar graph. If the categorical data appeared on the y-axis, the bars would run across the page making this a horizontal bar graph. The y-axis represents the number of tornadoes. This is the numerical or quantitative data.
|Approximate Time||15 Minutes|
|Pre-requisite Concepts||Students should be familiar with drawing bar graphs.|
|Type of Tutorial||Skills Application|
|Key Vocabulary||bar graph, data, table|