Graphing Basics

Why do we graph?

• Visual representation of data• “Short hand” for presenting large amounts

of information at once• Easier to visualize trends than by just using

numbers or figures• More organized way of showing information

Types of Graphs: Data TableHeight (cm) of Jr. High Students by Grade

7th 8th 9th140 152 160144 155 166144 160 162150 166 180155 150 175130 152 177133 144 152152 155 188140 155 159140 180 166141 182 165172 169 166180 160 167166 160 152154 160 184155 155 170138 175 170166 153 162181 140 166154 145 180

• Used to organize data collected

• Easily make transition from raw numbers into a visual representation

Types of Graphs: Bar Graph

• Shows data as a side-by-side comparison

• X axis is usually used to plot independent variable

• Y axis is usually used to plot dependent variable

Types of Graphs: Line Graph• Usually shows a

change over time or distance

• X axis is used to plot independent variable (time, distance, etc.)

• Y axis plots the dependent variable

Types of Graphs: Pie Chart• Shows parts of a whole

(percentages)

• Must have all data available and no groups can share any data

• Example: Can’t use a circle graph to show athletes by sport at TH Bell

Parts of a Graph

Graph Title

Y Axis Label- Include units

X Axis LabelLegend

Graph TitleY

Axis

Lab

el

LegendX Axis Label

Data Label

Data Label

Data Label

Data Label

Data Label

Graph Title