February, 2003
© 2000, 2001, 2003 Scott S. Emerson, M.D., Ph.D.
Ideal goal of
scientific study: Deterministic results
Determine
the exact value of a measurement or population parameter
·Prediction:
What will the value of a future observation be?
·Comparing
groups: What is the difference between response across two
populations?
Problem:
In the real world, few patterns are deterministic, so we do not
observe the same outcome for all individuals
·Hidden
(unmeasured) variables
·Inherent
randomness