1. The Scientific Method
An overview

2. What is Science? “Science” derived from Latin ‘to know’
Way of asking and answering questions While studying the natural world around you.
Seeking answers to questions about natural phenomena (we are therefore limited to what kinds of questions we ask)
Scientific thinking reduces emotional reactions

3. Scientific Design
Scientific knowledge begins with an observation and a proposed explanation.
Introduction – Background information about your topic
Hypothesis- an Explanation
A hypothesis is testable and falsifiable
In science hypotheses are tested by using them to make predictions about how a particular system will behave

4. Method: The process of exactly how you preformed the experiment described in exhaustive detail.
Results: Detailed charts, data tables and graphs that display your results
Conclusion: Detail analysis of your results, explain potential errors

6. Does it work? Scientific Method is a tool. Does this tool work?
Life expectancy
Mortality rates
Are there better tools?

7. Scientific Method in Action
We use the scientific method in everyday life
Example:
You got in your car to drive up here and turned the key but the car wouldn’t start (observation)

8. Scientific Method in Action
Example:
You got in your car to drive up here and turned the key but the car wouldn’t start (observation)
Hypothesis: There is something wrong with the car

9. Scientific Method in Action
Example:
You got in your car to drive up here and turned the key but the car wouldn’t start (observation)
Hypothesis: There is something wrong with the car
Hypothesis: battery dead, ignition problem,
out of gas

10. Scientific Method in Action
Test predictions (Method): turn on headlights, check spark plug wires, dip stick in gas tank

11. Scientific Method in Action
Test predictions: turn on headlights, check spark plug wires, dip stick in gas tank
Analyze results: headlights work, strong ignition spark, no gas on dip stick-gas gauge reads half full

12. Scientific Method in Action
Test predictions: turn on headlights, check spark plug wires, dip stick in gas tank
Analyze results: headlights work, strong ignition spark, no gas on dip stick-gas gauge reads half full
Conclusion: gauge inaccurate, out of gas

13. Example Hyp: King’s collar repels fleas
Pred: dogs wearing King’s collar will have fewer fleas than those without collar
IV: King’s collar DV: presence of fleas
CV’s: anything that might effect the number of fleas on the dogs
Can we think of some???

14. Experimental Design
Obtain 500 dogs of various breeds from local shelters. Have vet weed out the 200 dogs with the most fleas. Randomly assign individuals to 2 groups.
Board the dogs in identical environments and treat them the same except that one group gets to wear the King collar and the other group does not
After 2 wks. The dogs are examined by a vet for fleas.

15. Results: the dogs wearing the King collars were virtually free of fleas after the 2 wk period compared to the dogs without the collars which had about the same number of fleas as when the experiment began

16. Instrument: the object or survey that helps you collect data to be analzed.
Important terms:

17. Important terms:
Sample: a chosen population to represent a scientific study.
- Example: LHS students, Men, Asians
- Use common sense when choosing a sample
-Random sampling- Each member of the population has an equal chance of being selected. (best sample)
Experimental group: group(s) subjected to the independent variable
Control group: group not subjected to the independent variable, used as measuring stick

18. Reproducibility
reproducibility: producing the same result consistently to verify result. It is therefore important to describe your experimental design in enough detail for others to perform the same experiment.
A successful Experiment is repeatable.
By anyone.
Examples:
Cold Fusion (1989)
Ecstasy (Science, 2003)

19. Incorrect assumptions invalidate an experiment!
Assumptions: factors thought to be true for the investigation but have not been verified or controlled
Commonly accepted information
Thought to be held constant but not controlled
Factors beyond the investigators control because of technical or time considerations
Incorrect assumptions invalidate an experiment!

20. Statistics:
Statistics – using mathematics to organize, summarize, and interpret numerical data
Mean: arithmetic average of scores
Variability = how much scores vary from each other and from the mean

22. “There are three kinds of lies: lies, damned lies, and statistics”
- Benjamin Disraeli