Chapter 2 Organizing Data Section 1 Bar Graphs

Chapter 2: Organizing Data Section 1: Bar Graphs, Circle Graphs, and Time Plots

Characteristics of Graphs n · Title · Horizontal scale labeled n properly n · Vertical scale labeled n properly n · Colors explained n · Special symbols explained n · Abbreviations explained n · Data source · Avoids distortion, should not be misleading n

Bar Graphs – are useful for quantitative or qualitative data. With qualitative data, the frequency or percentage occurrence can be displayed. With quantitative data, the measurement itself can be displayed. Watch that the measurement scale is consistent or that a jump scale squiggle is used.

Bar Graph

Circle Graphs - display how a total is dispersed into several categories. The circle graph is very appropriate for qualitative data, or any data where percentage of occurrence makes sense. Circle graphs are most effective when the number of segments are ten or fewer.

Circle Chart

Time Plot n Time Plots – display how data change over time. It is best if the units of time are consistent.

Pareto Chart n Pareto chart – is a bar graph in which the bar height represents frequency of an event. In addition, the bars are arranged from left to right according to decreasing height.