Graphing Just the basics Graphs What are Graphs

Graphing (Just the basics. . . )

Graphs • • What are Graphs? Why do scientists use them? What other professional use graphs? Why in the world would anyone WANT TO use graphs?

3 Types

Line Graphs • The type most used on the Regents (99% of the time!) is a LINE GRAPH!

Rules for Line Graphs • Give your graph a Title – What are you graphing? • Label BOTH axes (X & Y) – Which one is the X axis? – Which one is the Y axis? • Label Appropriate Scale (Spaced EVENLY) • Use a key if plotting more than one source of data

Steps to follow • USE A PENCIL! • Label the horizontal and vertical axes – Independent Variable on the horizontal (HIV) – Dependent Variable on the vertical – Do NOT forget the units! • Number the horizontal and vertical axes – What is the largest number you need for your data? – How many lines are available? (Count ‘em!) – Can you skip any lines to spread the graph out? • Plot the data points (use small dots, NOT BASEBALLS!) • Connect the data points if told to do so • Title the Graph

Variables • Independent Variable (HIV) – This is what the experimenter CHANGES in the experiment • Sometimes called the Manipulated Variable – Goes on the X-axis! (Horizontal) • Dependent Variable (DVV) – The variable that is measured – Goes on the Y-axis! (Vertical)

Let's try it. . • Plot the following information on the graph and answer the questions. . . Time 1 2 3 4 5 6 7 12 16 21 20 24 22 26 (Days) Temp (Celcius) • • • What should the title be? What are the two variables? What is the unit for time? What is the unit for temperature? What is the Independent Variable (and where does it go on the graph? )

Let's try it. . again! • Plot the following information on the graph and answer the questions. . . Time 1 2 3 4 5 6 7 12 14 18 18 17 15 10 3. 5 2 . 5 0 0 1. 5 5 (Days) Temp (Celcius) Rainfall (cm) • What is the unit for rainfall? • Create a key!