Experimental Design and the Scientific Method

1. Experimental Design and the Scientific Method

2. Warm-up (8-27-14) • Write down what you think experimental design means • Why do you think experimental design is important? • Can you perform an experiment without thinking of “experimental design”?

3. Warm-up (8-28-14) • What are the steps of the scientific method? • Why does slope matter in science? • Give an example of a poorly designed experiment.

4. Outline • Objectives • Why do I care? • Slope Review • What is Experimental Design? • Purpose • Scientific Method • Steps

5. Objectives • Explain the purpose of experimental design and why it is important • Determine the difference between accuracy and precision • Explain the importance of the scientific method and why peer review is significant

6. Why Do I Care? • Experimental design determines the validity of the results presented • Determines whether or not you can trust the experiment • Scientific Method is the basis for all scientific thinking and questioning

7. Slope Review • Y=mx+b • What do these random letters mean?? • Why do we need slope? • The slope of a line is a rate of change and is represented by m. • When a line passes through the points
 (x1, y1) and (x2, y2),  the slope is
m = ???

9. What is Experimental Design?

10. What is the PURPOSE of Experimental Design? • Randomize • Even out effects we cannot control • Ensure equal chance to all possibilities • Control • Make sure we only get results for what we want

11. What is the PURPOSE of Experimental Design? • Replicate • Get as many replicates (repeats) as possible. • Results for a single subject might not be accurate. (No one is perfect on the first try all of the time.) • Block • Get rid of things we don’t want to study and that we can’t control • Best Experiments Are?? • The best experiments are usually randomized, comparative, double-blind, and placebo-controlled.

12. Parts of Experimental Design • Independent Variable • Dependent Variable • Hypothesis • Control • Replication • Purpose • Experimental Group(s) • Control Group • Constants

13. Let’s Try It! Experimental Design Practice (Remember our check list!) • What do we need to include / What questions do we have to answer? Superstitions • If you blow out all the candles on your birthday cake with the first puff you will get your wish.

14. You Try It! • Complete the activity with your table groups. I will number your tables! • Make sure that you are each writing down the answers on your own paper. • You will need these examples as a reference!

15. Superstitions used for practice with experimental design. • An apple a day keeps the doctor away. • Eating chocolate causes zits. • Shaving your legs makes the hair grow back more densely. • A knife placed under the bed during childbirth will ease the pain of labor. • Drinking coffee will stunt a child’s growth. • If you swim right after eating, you will get cramps. • If you catch a falling leaf on the first day of autumn, you will not catch a cold all winter. • If you go outside when your head is wet, you’ll catch a cold. • A red ribbon placed on a child who has been sick will keep the illness from returning. • A half onion placed under the bed of a sick person will reduce the fever. • Feed a cold, starve a fever. • Break a mirror and you will have seven years of bad luck. • Spit on a new bat before using it for the first time to make it lucky.

16. Warm-up (8-29-14) • Without experimental design and the scientific method, would there be valid experiments? What do you think? • https://www.youtube.com/watch?v=eA86dYxrg4Q

17. Outline • Objectives • Accuracy and precision • Scientific method

18. Objectives • Determine the difference between accuracy and precision • Explain the importance of the scientific method and why peer review is significant • Determine the importance of peer review and practice using peer review to evaluate the work of scientists.

19. Accuracy vs. Precision

20. Accuracy and Precision • Accuracy: • the degree to which the result of a measurement, calculation, or specification conforms to the correct value or a standard. • Precision: • Related to reproducibility and repeatability • Exactness • Related to those other points / values around it

21. Scientific Method • What is it? • It is a process that is used to find answers to questions about the world around us. • Is there only one Scientific Method? • No, there are several versions of the scientific method. Some versions have more steps, while others may have only a few. However, they all begin with the identification of a problem or a question to be answered based on observations of the world around us and provide an organized method for conducting and analyzing an experiment.

22. What is a hypothesis? • It is an educatedguess based on observations and your knowledge of the topic. • What is data? • It is information gathered during an experiment.

23. Steps • Identify the Problem What do you want to know or explain? • Form a Hypothesis What do you think will happen? • Create an Experiment How will you test your hypothesis? • Perform the Experiment Follow your procedure to test your hypothesis • Analyze the Data Is your data reliable? Does it support your hypothesis?

24. Simpson’s Experiments • Analyze the Simpson’s Experiments. • Keep in mind both experimental design and the scientific method. For each one, answer the four questions AS WELL AS these three prompts… • What is the Problem? • What is the Hypothesis? • What is the Data?

25. If your data is inaccurate or flawed… • Modify your experiment • Rewrite your procedure to address the flaws in the original experiment If your data is NOT inaccurate or flawed… • Communicate the Results • Write a conclusion that summarizes the important parts of your experiment and results. • Explain why you got the results that you did and what those results mean.

26. Ethical Traditions of Science • Value peer review • Truthful reporting of methods and outcomes • Making work public • Sharing a lens of professional skepticism when reviewing the work of others

27. Warm up (9-2-14) • Come in, grab a warm-up sheet from the front table, find your seat and get started answering your warm up.. • Design an experiment about the human body’s response to exercise. • Please be specific and detailed. Remember the parts of experimental design in your answer!

28. Outline • Objectives • Scientific Method Review • Peer Review • Experimental design Practice

29. Objectives • Determine the importance of peer review and practice using peer review to evaluate the work of scientists. • Practice experimental design and evaluating experiments using the guidelines established for good experimental design.

30. Scientific Method… • What is it? • Steps? • Tell me what you know

31. Peer Review a Scientific Article • Peer review methods are employed to maintain standards of quality, improve performance, and provide credibility. • Often used to determine an academic paper's suitability for publication. • http://science.howstuffworks.com/innovation/scientific-experiments/scientific-peer-review.htm

32. Media Sometimes Exaggerates Science • http://www.cmaj.ca/content/170/9/1399.full.pdf&embedded=true • What does this article have to say about the accuracy of reporting in the media?

33. Peer Review • Is the evidence presented appropriate and sufficient to support the claims?? • Physical Science • http://www.sciencedaily.com/releases/2010/08/100802101813.htm • Biology • http://www.thehindu.com/opinion/lead/lead-article-ebolas-reemergence-a-wakeup-call/article6357471.ece • Earth Systems • http://leisureguy.wordpress.com/2007/09/04/the-scientific-consensus-on-global-warming/ • Biology II • http://www.sciencedaily.com/releases/2014/08/140828142752.htm

34. Warm up (9-3-14) • Explain why experimental design is important to an experiment. • Describe how the scientific method, experimental design, and peer review are all connected.

35. Outline • Objectives • Peer Review Discussion • Experimental Design packet

36. Objectives • Practice using peer review to evaluate the work of scientists. • Practice experimental design and evaluating experiments using the guidelines established for good experimental design.

37. Discussion

38. Warm up (9-4-14) • What does peer review have to do with science? • What is the significance of making sure that everyone is using good experimental design techniques? • Do you need to use experimental design in this class? Why?

39. Outline • Objectives • Experimental Design packet • Experimental Design discussion

40. Objectives • Practice experimental design and evaluating experiments using the guidelines established for good experimental design.

41. Graphing Experimental Data • http://gbhsweb.glenbrook225.org/GBS/Science/chem/chem163/projects/factory/quiz.htm • Graph the results from the table • Be sure to label the axis and title your graph (keep in mind independent and dependent variables) • Use appropriate scales • How would I find the slope of this data?

42. What does the slope mean for science? • It is the interaction between the independent and the dependent variables Proportionality • two variables are proportional if a change in one is always accompanied by a change in the other, and if the changes are always related by use of a constant. • Directly proportional: y=cx • Inversely proportional: y=c/x

43. Inversely Proportional: when one value decreases at the same rate that the other increases. • Directly proportional: as one amount increases, another amount increases at the same rate.

45. Warm-up (9-5-14) • If you were planning on conducting an experiment and you wanted to make sure that you got funding… What are the steps you should be sure to follow? • What are the purposes of experimental design?

46. Outline • Objectives • Experimental Design Quiz • Ten Unanswered questions in science

47. Objectives • To demonstrate knowledge of Experimental Design and Peer Review • To explore the top 10 questions about the Earth and develop possible answers.

48. Earth Systems • Ten Unanswered Questions • http://www.livescience.com/4849-top-10-questions-earth.html

49. Quiz! • For this quiz… • No talking • You may use your notes, and only your notes • When you finish make sure that you are working on something to keep yourselves quiet. • If you talk after you have turned in your quiz, points may be taken off.