The scientific method

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The scientific method
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• A confusing aspect of science is that not all
  fields of science arrive at conclusions in the
  same way.
• The physical sciences, like physics and
  chemistry, use experimental forms of the
  "scientific method."
• The physical sciences do experiments to gather
  numerical data from which relationships are
  derived, and conclusions are made.

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The more descriptive sciences, like zoology and
anthropology

• May use a form of the method that involves
  gathering of information by visual observation or
  interviewing.
• What is common among all sciences, however, is
  the making of hypothesis to explain observations,
  the gathering of data, and based on this data,
  the drawing of conclusions that confirm or deny
  the original hypothesis.

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• The difference is in what is considered data, and
  how data is gathered and processed.

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• Observation
• A good scientist is observant and notices thing
  in the world around him/herself. (S)he sees,
  hears, or in some other way notices whats going
  on in the world and becomes curious about whats
  happening.
• Reading and studying what others have done in the
  past because scientific knowledge is cumulative.
• In physics, when Newton came up with his Theory
  of Motion, he based his hypothesis on the work of
  Copernicus, Kepler, and Galileo as well as his
  own, newer observations. Darwin not only observed
  and took notes during his voyage, but he also
  studied the practice of artificial selection and
  read the works of other naturalists to form his
  Theory of Evolution.

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• Hypotheses
• Can be proven wrong/incorrect, but can never be
  proven or confirmed with absolute certainty.
• It is impossible to test all given conditions,
  and someone with more knowledge, sometime in the
  future, may find a condition under which the
  hypothesis does not hold true.

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• Prediction
• Next, the experimenter uses deductive reasoning
  to test the hypothesis.
• Inductive reasoning goes from a set of specific
  observations to general conclusions I observed
  cells in x, y, and z organisms, therefore all
  animals have cells.

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• Deductive reasoning
• Flows from general to specific.
• From general premises, a scientist would
  extrapolate to specific results if all organisms
  have cells and humans are organisms, then humans
  should have cells. This is a prediction about a
  specific case based on the general premises.

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• Some Guidelines for Experimental Procedures
• Select only one thing to change in each
  experiment. Things that can be changed are called
  variables.
• Change something that will help you answer your
  questions.
• The procedure must tell how you will change this
  one thing.
• The procedure must explain how you will measure
  the amount of change.
• Each experiment should have a "control" for
  comparison so that you can see what the change
  actually did.

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• Your results can be invalid if your variables are
  not independent of one another, and you have not
  noticed this.
• Variables are independent if they produce their
  effects separately from each other.
• In other words, changing one variable does not
  affect changes produced by another variable.

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