Scientific Method and Theory

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Scientific Method and Theory

• Dr. James Danoff-Burg
• Columbia University

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Goals of science

• Describe the patterns that are found in the
  natural world
• Explain patterns
• This is the major emphasis of your individual
  project
• Ditto for most of the activities that we are
  doing in the class
• Scientific method is applicable to many other
  aspects of life

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Methods of Explanation

• Approximately 11 Steps
• Process is repeated many times
• Can NEVER prove a hypothesis
• Can only reject many, leaving one as best
  supported by the data
• Scientific Proof is a common fallacy

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Hypotheses

• Null hypothesis
• The hypothesis of no change
• Often abbreviated as Ho
• Alternative hypotheses
• Often abbreviated as Ha, Hb, etc.
• All must be mutually exclusive
• We accept one if Ho is statistically rejected
• Which Ha to accept is determined by trends in data

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Scientific Method - Steps 1-5

• Observe or suspect pattern
• Posit significance of observed difference
• Create question to explain pattern
• Create testable hypotheses
• Design experiment

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Scientific Method - Steps 6-11

• Collect data (Descriptive stage)
• Analyze data, primarily using statistics
• Evaluate hypotheses, reject Ho?
• Make conclusions based on data
• Note problems in current work
• Predict future directions for research

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Parts of a scientific report

• Title
• Abstract - an overall summary
• Introduction - background, question, Has
• Methods - what we did
• Results - what we found, graphs, summarized data
• Discussion - interpretations, predictions
• Acknowledgements - who helped us
• References - who we cited

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Scientific Communication

• Written report
• Traditional
• Oral presentation
• Commonly used for preliminary presentation of
  work to get feedback before writing it up
• Poster
• Visual summary of work - used at conferences
• Web page
• Can use a written report make it interactive

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Individual Projects Seven Parts to Design

• Question
• Null hypothesis Alternative hypotheses
• Independent variable(s)
• Dependent variables
• Desired data to collect
• Data collection method
• Expected outcome with reasons as to why you
  expect that