1. GRAPHING IN SCIENCE

2. Graphing Guidelines Descriptive title
Label each axis. Include Quantity and Units
Choose an appropriate range
Maximize your graph area a. Label each axis at regular increments
b. Use convenient increments
5. Plot points clearly and accurately. 

3. Variables
Independent – The data you know ahead of time, X-AXIS, the variable that is experimentally varied
Dependent -
– What you are trying to find out, What is observed, Y-AXIS
- It’s dependent on the independent variable

4. Dependent Variable
Independent Variable

5. Example
Place a D for dependent and an I for Independent below the correct variable. Then label the axes on the graphs.
1. Candy and Cavities
Candy –
Cavities - I D
Cavities
Candy

6. Example
Place a D for dependent and an I for Independent below the correct variable. Then label the axes on the graphs.
2. Grades and Hours of Studying
Hours of Study –
Grades - I D
Grades
Hour of Studying

7. Best Fit Line
A best fit line shows what you would expect to happen if you gathered more data than you have
It’s the one, straight line that is closest to all data points
Does not necessarily connect all data points
Like an average of all the points

8. Drawing a Best-Fit Line

9. GRAPHING RELATIONSHIPS

10. DIRECT RELATIONSHIP 5
As one variable increases, the other _____________ Line will slant ______ Y 4
Increases 3 Up 2 1 1 2 3 4 5 X

11. DIRECT RELATIONSHIP Examples Human Population versus Pollution
As the population increases, pollution increases

13. INDIRECT or INVERSE RELATIONSHIP5
As one variable increases, the other _____________ Line will slant ______ Y 4
Decreases 3 2
Down 1 1 2 3 4 5 X

14. INDIRECT or INVERSE RELATIONSHIP
Example
Elevation versus Air Temperature
The higher up you go in the sky, the air temperature is colder (decreases)

16. CONSTANT RELATIONSHIP5
As one variable increases, the other _____________ Line will Y 4
Stays the same 3 2
Go across or up and down 1 1 2 3 4 5 X

17. CONSTANT RELATIONSHIP
EXAMPLE
Hours in the day
Always stays at 24

18. CYCLIC RELATIONSHIP USED TO PREDICT CHANGE5
As one variable increases, the other_____________ Line will Y 4
Increases then decreases then increases, etc 3 2 1
Up, down, up, down, etc 1 2 3 4 5 X
USED TO PREDICT CHANGE

19. CYCLIC RELATIONSHIP
Tides