Nature of Science

1. Nature of Science

2. Key Term – define the following… • Data • The measurements and observations that are collected as a part of a research project, often a combination of measurements and descriptions.

3. Key Term – define the following… • Dependent Variable • What you measure in the experiment and what is affected during the experiment; responds to the independent variable; called dependent because it “depends” on the independent variable

4. Key Term – define the following… • Entity • The subject, specimen or item that is being studied

5. Key Term – Define the following… • Experiment • Test conducted as a part of the scientific method that includes a hypothesis; a variable that can be manipulated by the researcher (IV);and variable that can be observed, measured, calculated, and compared (DV).

6. Key Term – Define the following… • Independent Variable • The variable you have control over; what you can choose and manipulate. It is usually what you think will affect the dependent variable. This is the variable that you purposely manipulate.

7. Key Term – Define the following… • Scientific Method • An inquiry process used to systematically study, investigate, and provide explanations for observed phenomenon in the natural world • Usually involves the following steps… observation, background research, hypothesis, experiment, data analysis, conclusion, and retest. • This is you doing your absolute best to answer a question with the knowledge, skills, resources and technology you have available

8. Key Term – Define the following… • Constants • Factors within an experiment that are kept the same for all groups or trials in an attempt to reduce the influence of extraneous variables

9. Key Term – Define the following… • Control Group • Group in an experiment that receives the exact treatment as the experimental groups except it does NOT receive any change of the independent variable. • The group to which the experimental groups are compared

10. Key Term – Define the following… • Experimental Groups • Groups or trials in an experiment that receive all the same conditions except varying amounts or qualities of the independent variable

11. Key Term – Define the following… • Extraneous Variable • An undesirable variable in addition to the independent variable that may influence the results of an experiment, introducing error if it is not controlled as much as possible

12. Key Term – Define the following… • Hyp0thesis • A tentative and testable proposed explanation for an observable phenomenon

13. Writing Hypotheses • Your hypothesis should include: • Independent variable • Dependent variable • A prediction of what kind of effect the IV will have on the DV (should be based on your background research!) • When possible quantify your hypothesis

14. Writing Hypotheses • Start with a draft using any of the following sentence formats as a guide: • If __(IV)__ is related to __(DV)__, then (predict the effect). • If the __(IV)__ is (describe the changes), then the __(DV)__ will (predict the effect). • __(DV)__ will (predict the effect when) __(IV)_ (describe the changes).

15. Key Term – Define the following… • Inference • A conclusion, based on facts, that a person perceives to be true

16. Key Term – differentiate between the two… Qualitative Data Quantitative Data • Data that describe characteristics or qualities, such as color, odor, or texture • Data that describe category frequency or ratings, such as, stem sturdiness • Data that use numbers with a unit of measurement, such as the length of an insect in millimeters or the weight of a projectile in kilograms

17. Key Term – Define the following… • Trial • Replication of experimental and control groups; used to decrease the influence of variations associated with the independent variable, researcher measurement error, and difference between entities studied

18. Research Design includes… • Hypothesis • Variables • Experimental groups • Control groups • Constants

19. Experimental Design Diagram

20. Let’s practice… • Tomato…