Scientific Methods

1
Scientific Methods

• I. Hypothetical Deductive Method
• many hypothesis (ideas),
• eliminate those without data to support them
• II. Correlation Method
• multi variable situations
• Use statistics and computer models to compare
  data to situations
• (predict the weather)

2
Steps in (a) Scientific Method (Hypothetical
deductive)Used more like a flow chart than a list

• Observation
• Curiosity, skepticism, senses/ observations,
  experiences
• Question
• Why? , How? , What if?
• 3. Research
• background information , look for an answer,
  list all possible explanations, what you already
  know
• 4. Hypothesis
• If then therefore statement, cause and
  effect, educated guess, prediction, testable/
  measurable, explanation on trial claims and
  statements

3
Scientific method continued

• 5. Design an Experiment
• Independent variable manipulated
  variable
• I/ the scientist manipulate or investigate,
• only 1, the IF..,
• what is being tested/varied/modified/changed by
  the researcher,
• x axis
• Dependent variable responding variable
• depends on what I did (independent) plant is
  TALLER because of the fertilizer,
• Then, what is measured/changes, y axis
• Controls
• everything you keep the same so that there is
  only one independent variable., comparison/ base
  line, control group

4
Scientific method continued

• Collect data (during and after experiment)
• numbers and units quantitative data (quantity
  or amount),
• descriptions qualitative data (quality
  of something)
• 7. Analyze data
• Put into tables, charts, graphs, look for TRENDS
  and correlations between Ind.V and Dep. V.,
  relationships. Show work, calculations and
  formulas
• Either verify or falsify your claim with these
  steps retest, restart, restate, re-evaluate
• 8. Conclusion
• Does your data show support for your prediction.
  Accept Hypothesis or declare Null Hypothesis.
  Explain what happened, what your results were and
  where you could improve/change (error analysis is
  statistical work done to show the precision of
  your measurements)
• Do not say Prove you didnt prove 100
  forever, you supported or eliminated, until there
  is new evidence
• 9. Repeat/ report/ publish
• Lab report or publication grant money, peer
  review, share results, more testing, etc.

5
Assignment this may be done individually or in
collaboration with a lab group

• 1. on a sheet of plain paper (or your iPad)
  create a flow chart version of the steps usually
  covered in a scientific experiment.
• 2. Read page 29 - 31 and list the steps taken by
  Rita Colwell to verify or correlate that water
  temperature is an indicator of cholera risk.
• 3. Choose an article from the red folders
  provided and list the steps taken during a
  classic experiment (Redi, Lister, Pasteur,
  Jenner, etc)

What was the hypothesis or claim? Set up/
control group, procedure Independent
variable, dependent variable, data or results,
Conclusion/ eliminate or support