1. Showing patterns & trends
Graphing Your Data
Showing patterns & trends
A picture is worth a thousand words!

2. Types of data (information)
Variables
what you measure in an experiment
dependent variable
measured variable
unpredictable change: we don’t know how it will change until we do the experiment
Y-axis
independent variable
manipulated variable
predictable change: it only changes because we chose how it would change
X-axis
The effect of _____________ on _____________
INDEPENDENT
DEPENDENT

3. Examples of experiments 1
How does fertilizer affect the growth rate of plants?
we set up an experiment testing different amounts of fertilizer on different plants & measuring the growth (height) of the plants:
dependent variable (Y-axis)?
height of plants
independent variable (X-axis)?
amount of fertilizer
The effect of _____________ on _____________
Amount of Fertilizer
Height of Plants

4. Examples of experiments 2
How does exercise affect heart rate of 10th grade student?
we set up an experiment testing different lengths of time of exercise (minutes) on the heart rate of students:
dependent variable (Y-axis)?
heart rate
independent variable (X-axis)?
minutes of exercise
The effect of _____________ on _____________
Exercise
Heart Rate

5. Examples of experiments 3
What’s the favorite drink of students?
we set up an experiment surveying students and asking which is their favorite drink :
dependent variable (Y-axis)?
number of students
independent variable (X-axis)?
type of drink
The effect of _____________ on _____________
Type of Drink
How many students chose it

6. Making pictures out of data
Graphs
line graphs
graphing data to show change over time
bar graphs (or histograms)
graphing data to compare categories or groups
pie charts
use when comparing percentages or amounts
How’s a critter to choose?

7. elevation (feet above sea level)
How does elevation affect temperature?
Line graph!
elevation (feet above sea level)
temp.
(°C) 30
500 25
1000 20
1500 15
2000 10
2500 5 30 25 20 18
temperature 15 10
1200 ft? 5
500
1000
1200
1500
2000
2500
elevation

8. Which drink do you like best?
number
Coke 1
Pepsi
Water 4
Iced tea
Gatorade 3 6
Bar graph! 5 4
temperature 3 2
Red Bull? 1
Coke RB
Pepsi RB
water
tea
Gatorade
elevation

9. Rules to Follow for Graphing
Must have a title
Label the x and y axis
Choose a scale for each axis (numbers that make sense!)

10. Any Questions??