1. @ 2012 Wadsworth, Cengage Learning Chapter 3 Developing the Hypothesis @ 2012 Wadsworth, Cengage Learning

2. Topics 1.Making Our Hypotheses Concrete 2.Making Our Hypotheses Logical 3.Creating Testable Research Hypotheses and the Problem of Measurement 4.Overview 5.Ideas Come From Everywhere 6.Intuition and Revelation 7.The Scientist’s Guide to Having an Idea 8.Tools for Library Research

3. @ 2012 Wadsworth, Cengage Learning Making Our Hypotheses Concrete

4. @ 2012 Wadsworth, Cengage Learning Making Our Hypotheses Concrete Dilemma – How can we scientifically evaluate our private ideas about the world? One answer – Define private ideas in terms of specific behaviors that anyone can witness

5. @ 2012 Wadsworth, Cengage Learning Making Our Hypotheses Concrete (cont’d.) Operational definition – Representations of psychological events in the physical world – Defines events in terms of the operations required to measure them – Takes a general concept and places it within a given context

6. @ 2012 Wadsworth, Cengage Learning Figure 3.1 From any one global construct, there are several possible operational definitions, depending on the questions asked and the type of population studied

7. @ 2012 Wadsworth, Cengage Learning Making Our Hypotheses Concrete (cont’d.) Construct validity – Asks whether the procedure that we are using is an adequate definition of the construct that we are measuring – Example: ask whether a particular measure of depression allows us to make valid inferences about the construct of depression

8. @ 2012 Wadsworth, Cengage Learning Making Our Hypotheses Logical

9. @ 2012 Wadsworth, Cengage Learning Making Our Hypotheses Logical The “I wonder what will happen if” hypothesis and inductive reasoning – Generalizing from a specific instance to a more general idea – Example: observing a chimpanzee using sign language with a person, and concluding that chimpanzees can communicate with humans – Danger: overlooking unobserved factors that may be responsible for the effects that we observe

10. @ 2012 Wadsworth, Cengage Learning Figure 3.2 Inductive and deductive relationships between observation and theory

11. @ 2012 Wadsworth, Cengage Learning Making Our Hypotheses Logical (cont’d.) The “I expect this would happen if” hypothesis and deductive reasoning – Takes the form of an if-then statement – If my idea about the world is correct, then this cause should produce the following effect – Example: “If it is true that schizophrenia is determined genetically, then we should find a greater incidence of the disorder between twins than between strangers”

12. @ 2012 Wadsworth, Cengage Learning Making Our Hypotheses Logical (cont’d.) Four steps that characterize strong inference – Devise alternative hypotheses – Devise a crucial experiment with alternative possible outcomes – Carry out the experiment – Return to step 1 with further refinements of the supported hypothesis

13. @ 2012 Wadsworth, Cengage Learning Making Our Hypotheses Logical (cont’d.) Platt sees strong inference as: – A method for rapid progress in science – A procedure at the heart of every scientist’s thinking: Obviously it should be applied as much to one’s own thinking as to others’. It consists of asking in your own mind, on hearing any scientific explanation or theory put forward, “But sir, what experiment could disprove your hypothesis?”; or on hearing a scientific experiment described, “But sir, what hypothesis does your experiment disprove?” (Platt, 1964, p. 352)

14. @ 2012 Wadsworth, Cengage Learning Creating Testable Research Hypotheses and the Problem of Measurement

15. @ 2012 Wadsworth, Cengage Learning Creating Testable Research Hypotheses Transition from a general idea to a specific research hypothesis requires careful thought It is not always easy to ask a question that can be answered scientifically Measurement: one aspect of the transition to a testable research hypothesis For a method of measurement to pass the test of reliability, the measurements must be consistent

16. @ 2012 Wadsworth, Cengage Learning Creating Testable Research Hypotheses (cont’d.) Test–retest reliability: correlation between the scores on each of the testing occasions For a method of measurement to pass the test of validity, it must be accurate To be valid, a measurement must reflect the true score within certain limits Choose methods of measurement that are both accurate (valid) and consistent (reliable)

17. @ 2012 Wadsworth, Cengage Learning Overview

18. @ 2012 Wadsworth, Cengage Learning Figure 3.3 Steps required before experimentation

19. @ 2012 Wadsworth, Cengage Learning Ideas Come from Everywhere

20. @ 2012 Wadsworth, Cengage Learning Figure 3.4 Steps involved in forming a research hypothesis

21. @ 2012 Wadsworth, Cengage Learning Intuition and Revelation

22. @ 2012 Wadsworth, Cengage Learning Intuition and Revelation We do not know much about the workings of our brains We do not know where spontaneous ideas come from We can examine cases in which spontaneous ideas have influenced the course of science

23. @ 2012 Wadsworth, Cengage Learning Intuition and Revelation (cont’d.) When asked how he came upon ideas and solved problems, Einstein replied: The words or the language, as they are written or spoken, do not seem to play any role in my mechanism of thought.... The above mentioned elements are, in any case, of visual and some of muscular type. Conventional words or other signs have to be sought for laboriously only in a secondary stage. (Koestler, 1964, p. 171)

24. @ 2012 Wadsworth, Cengage Learning Intuition and Revelation (cont’d.) Simple dream of a snake biting its own tail – Led to the idea of a ring of carbon atoms Spontaneity of insights – Preceded by years of intensive work Insights had to be translated into workings of science

25. @ 2012 Wadsworth, Cengage Learning The Scientist’s Guide to Having an Idea

26. @ 2012 Wadsworth, Cengage Learning The Scientist’s Guide to Having an Idea Graham Wallas (1926) described the scientific process in four stages: – Preparation: person becomes interested in a problem – Incubation: close to meditating on a topic but not thinking about it – Illumination: solution begins to emerge into consciousness – Verification: when you test your idea

27. @ 2012 Wadsworth, Cengage Learning Tools for Library Research

28. @ 2012 Wadsworth, Cengage Learning Tools for Library Research Journals: major outlet in which scientists describe their research Peer review: experts in the author’s particular field read the paper and gave suggestions before the article was published Computer databases: useful for their ability to search for categories of research that normally might not be indexed

29. @ 2012 Wadsworth, Cengage Learning Box 3.1

30. @ 2012 Wadsworth, Cengage Learning Tools for Library Research (cont’d.) PubMed – Performs the same function as PsycINFO but for medical journals – Assesses a database called MEDLINE, which is part of the U.S. National Library of Medicine – Accessed through a variety of sources, including the PubMed website: http://www.ncbi.nlm.nih.gov/PubMed

31. @ 2012 Wadsworth, Cengage Learning Box 3.2

32. @ 2012 Wadsworth, Cengage Learning Tools for Library Research (cont’d.) Science Citation Index (SCI) and the Social Science Citation Index (SSCI) – List articles published in either the sciences or the social sciences – Found in an online site entitled Web of Science Internet – No guarantee that the information you receive is always correct or unbiased – Go to sites maintained by major institutions

33. @ 2012 Wadsworth, Cengage Learning Summary Creating an operational definition is one way researchers clarify their ideas Scientists obtain ideas for research from a variety of sources Wallas suggested four stages: preparation, incubation, illumination, and verification Reference libraries contain important tools for helping us find articles