GRAPHING GRAPHING BASICSBASICSModifieid from:Modifieid from:

http://southcobbhs.typepad.com/files/http://southcobbhs.typepad.com/files/day-2-graphing-basics.pptday-2-graphing-basics.ppt

Data ManagementData Management When performing an experiment, you will When performing an experiment, you will

always collect dataalways collect data REVIEWREVIEW

Quantitative dataQuantitative data – Data gathered by making – Data gathered by making observations using your senses and observations using your senses and includes numbersincludes numbers

Qualitative dataQualitative data – Data gathered by making – Data gathered by making observations using your senses and does observations using your senses and does NOT include numbersNOT include numbers

Regardless of the type of data that you Regardless of the type of data that you collect, it should be properly organized in a collect, it should be properly organized in a data table.data table.

Data Table FormatData Table Format The proper format for a The proper format for a

data table is:data table is: Place your independent Place your independent

variable and unit in the variable and unit in the left-most columnleft-most column

Place your dependent Place your dependent variable and unit in the variable and unit in the right-most columnright-most column

REVIEW:REVIEW: Independent VariableIndependent Variable

The thing that is changed by The thing that is changed by the experimenter the experimenter

Dependent VariableDependent Variable The thing that is measured in The thing that is measured in

the experimentthe experiment

Practice ScenarioPractice ScenarioFor the following scenario, pull out the parts indicated:For the following scenario, pull out the parts indicated:

Laura was watching a special on HGTV (Home and Garden TV) that was Laura was watching a special on HGTV (Home and Garden TV) that was on the effects of different amounts of fertilizer on plant growth. It said on the effects of different amounts of fertilizer on plant growth. It said that the more fertilizer that could be added, the more the plants would that the more fertilizer that could be added, the more the plants would grow. She decided to experiment to see if it was true. She went to her grow. She decided to experiment to see if it was true. She went to her garden and removed 6 tulip bulbs. She placed them in 6 identical pots, garden and removed 6 tulip bulbs. She placed them in 6 identical pots, watered them with the same amount of water. She decided to add the watered them with the same amount of water. She decided to add the following amounts of fertilizer to the plants: Plant A (0g); Plant B (3g); following amounts of fertilizer to the plants: Plant A (0g); Plant B (3g); Plant C (6g); Plant D (9g). She went back after 10 days and measured Plant C (6g); Plant D (9g). She went back after 10 days and measured the height of each plant. She measured the plants as follows: Plant A the height of each plant. She measured the plants as follows: Plant A

(5cm), Plant B (7cm), Plant C (9cm), Plant D (11cm).(5cm), Plant B (7cm), Plant C (9cm), Plant D (11cm).

What is the hypothesis? What is the hypothesis?

What is the Control? What is the Control?

What are the Constants? What are the Constants?

What is the Independent Variable? What is the Independent Variable?

What is the Dependent Variable?What is the Dependent Variable?

If I add more fertilizer, then the plants will grow more.If I add more fertilizer, then the plants will grow more.

Plant APlant A

Pots, tulips, water, measured after same amt. of timePots, tulips, water, measured after same amt. of time

Amount of fertilizerAmount of fertilizer

Plant growthPlant growth

Practice Scenario (continued)Practice Scenario (continued)

Now, using your Now, using your answers from the answers from the previous slide, previous slide, correctly fill in the correctly fill in the data table below. data table below. Consult the Consult the scenario to find the scenario to find the proper numbers to proper numbers to put in the table as put in the table as well. well.

AA

BB

CC

DD

00

33

66

99

55

77

99

1111

Types of GraphsTypes of Graphs After collecting your data, you will After collecting your data, you will

need to organize it into a graph.need to organize it into a graph. We will be using the following form of We will be using the following form of

graphinggraphing

Line GraphLine Graph

Why Graph?Why Graph? Graphs are an effective way to visually Graphs are an effective way to visually

display the information or data collected display the information or data collected in an experiment.in an experiment.

Graphs can clearly illustrate a Graphs can clearly illustrate a trendtrend in in information or data collected. This is one information or data collected. This is one way that data can be analyzed.way that data can be analyzed.

Line GraphLine Graph Most often used to Most often used to

show changes over show changes over time or rates of change time or rates of change in something. It is used in something. It is used when you can make a when you can make a sequential scale with sequential scale with the data being the data being collected. collected.

Example:Example: Change in average Change in average

speed compared to the speed compared to the distance traveled. distance traveled. Note: In our lab, we will be

using best fit lines for our results.

Titling a GraphTitling a Graph A title for a graph should describe what A title for a graph should describe what

the experiment was comparingthe experiment was comparing Titles will often list the dependent variable and Titles will often list the dependent variable and

the independent variablethe independent variable All titles are placed at the TOP of the All titles are placed at the TOP of the

graphgraph

Bar & Line Graphs Bar & Line Graphs Line graphs are Line graphs are

constructed on a set of constructed on a set of axes axes X axis runs horizontalX axis runs horizontal

( ( →→)) Y axis runs vertical Y axis runs vertical

((↑↑)) These axes must be These axes must be

labeled properlylabeled properly The x-axis should be The x-axis should be

labeled with the labeled with the independent variable and independent variable and unitunit

The y-axis should be The y-axis should be labeled with the dependent labeled with the dependent variable and unitvariable and unit

Y-axisY-axis

X-axisX-axis

Practice Scenario (continued)Practice Scenario (continued)

Now, using your answers from the earlier scenario, Now, using your answers from the earlier scenario, correctly title and label the axes below: correctly title and label the axes below:

AA

BB

CC

DD

00

33

66

99

55

77

99

1111

Line GraphLine Graph

AA

BB

CC

DD

00

33

66

99

55

77

99

1111

Plant Growth Depending on Amount of Fertilizer Used

5

7

9

11

0

2

4

6

8

10

12

0 5 10

Amount of Fertilizer (grams)

Pla

nt

Gro

wth

(c

m)