What is Science?

1. What is Science? Psyc 362 Research Methods in Psychology Chapter 2 James A. Van Slyke

2. Historical Roots • 1920’s Logical Positivism and the Vienna Circle • Attempting to distinguish between science and metaphysics (problem of demarcation) • Attempting to reconstruct all scientific knowledge from experience – empiricism – ‘bottom-up’

3. Philosophical Roots • Karl Popper (1902-1994) • Scientific theories are those theories that are falsifiable • Scientific theories should continually be in competition • Those theories that withstand continued experimentation are vindicated

4. Philosophical Roots • Carl Hempel (1905-1997) • “hypothetico-deductive” method in science • A hypothesis is accepted or rejected according to its ability to explain data • Hypothesis are never proven is a straight-forward manner, dependent upon how much later research supports or rejects it

5. The Scientific Method • Theory • A scientific theory explains through an integrated set of principles that organizes and predicts behaviors or events Theory Hypothesis Data

6. The Scientific Method • Hypothesis • Identifying a testable prediction based on the theory Theory Hypothesis Data

7. The Scientific Method • Testing • Doing the actual research by application of the hypothesis • Using statistics to infer characterizations Theory Hypothesis Data

8. The Scientific Method • All three interconnected • Separate, yet inform each other • Method moves in a circle Theory Hypothesis Data

9. Progress in Science • Imre Lakatos (1922-1974) • Science progresses through competing research programs • Composed of theories, hypotheses and data • Research programs progress by explaining data over time • Explain data better than a competing programs

10. The Logic of Scientific Discovery • Law • Theory • Hypothesis

11. The Logic of Scientific Discovery • Law- universal statement about the nature of things that allows reliable predictions of future events • The most significant laws in science are the laws of conservation • Energy- total amount of energy in an isolated system remains constant • Momentum- tendency of an object to continue to move in its direction of travel unless acted upon by an outside force

12. The Logic of Scientific Discovery • Theory- a general statement about the causal relation between two or more variables • Must adhere to the canons of science • Theory of evolution • Theory of classical conditioning • Principle of equifinality- the same behavior is often produced by many different causes

13. The Logic of Scientific Discovery • Hypothesis- prediction about a specific event derived from one or more theories • If the prediction does not prove true, what does this mean in regards to the theory?

14. The Science of Observation • Induction vs Deduction

15. The Science of Observation • Induction- reasoning from specific instances to general principles • Method of Induction- making many observations under controlled conditions and arriving at a general statement • Francis Bacon

16. The Science of Observation • Problem of Induction- How do you know when you’ve made enough observations to be sure that a theory can be labeled a law, i.e. that it will always be true. • David Hume- it is always possible that the very next observation could violate previous conclusions regardless of the number of observations that you make.

17. The Science of Observation • Deduction- reasoning from general principles to specific instances • Deduction in science- when theories are used to develop hypotheses that are then tested against observations.

18. Three Approaches to Hypothesis Testing • Validation • Falsification • Qualification

19. Three Approaches to Hypothesis Testing • 2-4-6 task

20. Fig. 13.3 If a card has a vowel on one side, it must have an even number on the other side. 96% of participants give wrong answers on this problem

21. Three Approaches to Hypothesis Testing • Positive Test Bias (Confirmation Bias)- tendency for people who are evaluating hypotheses to attempt to confirm rather than disconfirm these hypotheses. • Behavioral Confirmation- tendency for social perceivers to elicit behaviors from a person that are consistent with their initial expectancies of the person.

22. Fig. 13.4 If a person is drinking an alcoholic beverage then they must be over 21 years of age.

23. Three Approaches to Hypothesis Testing • Validation- researchers attempt to gather evidence that supports or confirms a theory or hypothesis • Falsification- researchers attempt to gather evidence that invalidates or disconfirms a theory or hypothesis • Qualification- researchers attempt to identify the boundary conditions under which a theory or hypothesis is and is not true

24. The Art of Scientific Discovery • Inductive Techniques for Developing Ideas (reasoning from the specific to the general) • Case studies • Paradoxical incidents • Analyzing the practitioner’s rule of thumb • Serendipity

25. The Art of Scientific Discovery • Deductive Techniques for Developing Ideas (reasoning from the general to the specific) • Reasoning by analogy • Applying a functional or adaptive analysis • Hypothetico-deductive method • Accounting for conflicting results • Accounting for exceptions