scientific method: experimental design and laboratory report writing available online @ available...

Scientific Method: Experimental Design

and Laboratory Report Writing

Scientific Method: Experimental Design

and Laboratory Report Writing

Available online @http://www.redwood.org/

stewart

Available online @http://www.redwood.org/

stewart

Choose a topicChoose a topicObserve the world around you!Consider:Prior experienceInitial testingRESEARCH

Observe the world around you!Consider:Prior experienceInitial testingRESEARCH

EXAMPLE:After studying about recycling, members of John’s biology class investigated the effect of various recycled products on plant growth. John’s lab group compared the effect of different aged grass compost on bean plants. Because decomposition is necessary for release of nutrients, the group hypothesized that older grass compost would produce taller bean plants. Three flats of bean plants (25 plants/flat) were grown for 5 days. The plants were then fertilized as follows: (a) Flat A: 450 g of 3-month-old compost, (b) Flat B: 450 g of 6-month-old compost, and (c) Flat C: 0 g compost. The plants received the same amount of sunlight and water each day. At the end of 30 days the group recorded the height of the plants (cm), and plant health was described.

Choose topic Experimental Organizer Data Laboratory Report

Experimental OrganizerExperimental Organizer

To get you started, organize your ideas into an Experimental Organizer. Eventually, you will use this to write your complete Laboratory Report.

To get you started, organize your ideas into an Experimental Organizer. Eventually, you will use this to write your complete Laboratory Report.


TitleTitle

The effect of IV on DV.The effect of IV on DV.

EXAMPLE:The Effect of Different Aged Compost on Bean Plant Growth.

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are needed to see this picture.


HypothesisHypothesis

If IV then DV.Be specific.

If IV then DV.Be specific.

EXAMPLE:If older compost is applied, then plant height will be taller

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are needed to see this picture.


Independent Variable (IV)

Independent Variable (IV)

What will be purposefully changed by the experimenter. What you are testing. There is only ONE IV in a controlled experiment!

What will be purposefully changed by the experimenter. What you are testing. There is only ONE IV in a controlled experiment!EXAMPLE:Age of Compost


Levels (Treatments) of IV

Levels (Treatments) of IV

Specific changes that will be made to the IV.

One is the control: The standard for comparing experimental effects.

Specific changes that will be made to the IV.

One is the control: The standard for comparing experimental effects.

EXAMPLE:

Levels of I.V.(2 or more plus the control, which must be identified)

3 monthold

compost

6 monthold

compost

NoCompost(control)


Number of TrialsNumber of Trials

Number of replications of each level/treatment.

At least 2 trials per level/treatment.

Number of replications of each level/treatment.

At least 2 trials per level/treatment. EXAMPLE:

Number of tr ials you will conduct for each I.V. level

25 plants

25 plants

25 plants


Dependent Variable (DV)

Dependent Variable (DV)

Variable that “depends” on the IV. Your RESULTS.

Specifically: Quantitative Measurements: NUMBERS (Quantities)

Qualitative Measurements: CHARACTERISTICS (Qualities)

Variable that “depends” on the IV. Your RESULTS.

Specifically: Quantitative Measurements: NUMBERS (Quantities)

Qualitative Measurements: CHARACTERISTICS (Qualities)

EXAMPLE:Quantitative Measurements: Height of plants (cm)Qualitative Measurements: Plant Health description


ConstantsConstants

Procedures and materials used throughout experiment to assure there is only one Independent Variable.

Procedures and materials used throughout experiment to assure there is only one Independent Variable.

EXAMPLE:Amount of light, amount of water, amount of compost


The Experimental Organizer will help describe your experimental PROCEDURES in detail. Include:

MATERIALS STATE IV, DV, CONSTANTS, ETC.

SET-UP PROCEDURES DATA COLLECTION PROCEDURES

The Experimental Organizer will help describe your experimental PROCEDURES in detail. Include:




Looking ahead: Use the Experimental Organizer to--among other things-- write your PROCEDURES in the EXPERIMENTAL DESIGN section of your Laboratory Report.

Data TablesData Tables1. Make a table containing vertical columns for (1) the independent variable, (2) dependent variable and (3) statistical calculations (i.e. mean). Use a ruler. * are the cells of your table large enough?2. Subdivide the column for the dependent variable to reflect the number of trials.3. Under the I.V. column, list the levels (treatments) of the independent variable in rows – preferably from the smallest to the largest.4. Title the data table (The Effect of I.V. on. D.V.)5. Record all data values and calculations in the appropriate locations!

1. Make a table containing vertical columns for (1) the independent variable, (2) dependent variable and (3) statistical calculations (i.e. mean). Use a ruler. * are the cells of your table large enough?2. Subdivide the column for the dependent variable to reflect the number of trials.3. Under the I.V. column, list the levels (treatments) of the independent variable in rows – preferably from the smallest to the largest.4. Title the data table (The Effect of I.V. on. D.V.)5. Record all data values and calculations in the appropriate locations!

EXAMPLE:Height of Plants at 30 Days

(cm) Age of Compost

(months) Trials

Mean Plant Height (cm)

1 2 3 4 etc. 0 months (control)

3 months 6 months


GraphsGraphsUse Data Tables to create Graphs

1.Identify dependant (y-axis) and independent (x-axis) variables (Y depends on X) the dependant variable is the variable you are measuring the independent variable is the variable you are testing - or the one that you are changing

2. Establish/calculate a scale for each axis

what is the range for the data?how accurate do you need to be?what are my graph paper limitations

(if any)? 3.Bar (DISCONTINUOUS data) or Line Graph

(CONTINUOUS data)? 4.Label the x-axis and y-axis (designate

units in parenthesis) 5.Title the graph: The Effect of

Independent Variable on Dependent Variable (*same as data tables!)

Use Data Tables to create Graphs

1.Identify dependant (y-axis) and independent (x-axis) variables (Y depends on X) the dependant variable is the variable you are measuring the independent variable is the variable you are testing - or the one that you are changing

2. Establish/calculate a scale for each axis

what is the range for the data?how accurate do you need to be?what are my graph paper limitations

(if any)? 3.Bar (DISCONTINUOUS data) or Line Graph

(CONTINUOUS data)? 4.Label the x-axis and y-axis (designate

units in parenthesis) 5.Title the graph: The Effect of

Independent Variable on Dependent Variable (*same as data tables!)


The Effects of the Amount of Compost on the Height of Bean Plants

0.0

5.0

10.0

15.0

20.0

25.0

30.0

0.0 g 10.0 g 20.0 g 30.0 g 40.0 g 50.0 g

Amount of Compost (grams)

Height of Plants (cm)

Mean Plant Height

GraphsGraphs


FOR QUALITATIVE DATA:

Frequency of MODE, or

Frequency of one or more of the dependent variables


FOR QUALITATIVE DATA:

Frequency of MODE, or

Frequency of one or more of the dependent variables


The Effect of the Amount of Compost on the Overall Health of Bean Plants

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

0.0 g 10.0 g 20.0 g 30.0 g 40.0 g 50.0 g

Amount of Compost (grams)

Frequency Distribution

UN = Unhealthy

H = Healthy

Laboratory ReportLaboratory ReportUse your Experimental Organizer and other information to write a full Laboratory Report which includes:

A. TITLE B. INTRODUCTION C. HYPOTHESIS D. EXPERIMENTAL DESIGN E. DATA F. DISCUSSION G. CONCLUSION H. REFERENCES CITED

Use your Experimental Organizer and other information to write a full Laboratory Report which includes:

A. TITLE B. INTRODUCTION C. HYPOTHESIS D. EXPERIMENTAL DESIGN E. DATA F. DISCUSSION G. CONCLUSION H. REFERENCES CITED


A. TitleA. Title

Use Title from Experimental Organizer.

Use Title from Experimental Organizer.


B. IntroductionB. IntroductionConduct further research and write a complete Introduction. Stating:

BACKGROUND: WHATRATIONALE, PURPOSE: WHY do this experiment

explain HYPOTHESIS: HOWyou expect it will turn out

Conduct further research and write a complete Introduction. Stating:

BACKGROUND: WHATRATIONALE, PURPOSE: WHY do this experiment

explain HYPOTHESIS: HOWyou expect it will turn out


C. HypothesisC. Hypothesis

Use Hypothesis from Experimental Organizer.

Use Hypothesis from Experimental Organizer.


D. Experimental DesignD. Experimental Design Using Experimental Organizer as a start, describe your experimental PROCEDURES in detail. Include:



Using Experimental Organizer as a start, describe your experimental PROCEDURES in detail. Include:




E. DataE. DataInclude Data Tables and GraphsInclude Data Tables and Graphs


F. DiscussionF. Discussion Discuss data in detail: WHAT happened.

Identify trends and anomalies.

Explain WHY you got the results you did.

Compare findings with other research/results.

Suggest HOW to improve, further the study.

Discuss data in detail: WHAT happened.

Identify trends and anomalies.

Explain WHY you got the results you did.

Compare findings with other research/results.

Suggest HOW to improve, further the study.


G. ConclusionG. Conclusion

Restate purpose, summarize results in relation to Hypothesis.

Restate purpose, summarize results in relation to Hypothesis.


H. References CitedH. References Cited

List sources used.List sources used.


scientific method: experimental design and laboratory report writing available online @ available...

Documents

compost control

g compost

monthold compost

older compost

age of compost

month old compost

older grass compost

height of plants