Experimental Design

Psych 275

The Basis of Our Science

What is Psychology?

• Is it Science?

• Is it A science?

• Is it a collection of “sciences”?

• What does Psychology consist of today?

• Is there a common, overarching, concept?

• Why do we need to answer this question?

What is Science?

• Science (from Latin scientia - knowledge) refers to the system of acquiring knowledge – based on empiricism, experimentation, and methodological naturalism. The term science also refers to the organized body of knowledge humans have gained by such research.

What is Science?

• Most scientists maintain that scientific investigation must adhere to the scientific method, a process for evaluating empirical knowledge which explains observable events in nature as a result of natural causes, rejecting supernatural notions. Less formally, the word science often describes any systematic field of study or the knowledge gained from it. Particular specialized studies that make use of empirical methods are often referred to as sciences as well. This article concentrates on the more specific definition.

What is Science?

• Fields of science are commonly classified along two major lines:

• Natural sciences, the study of the natural phenomena including biology;

• Social sciences, the systematic study of human behavior and society.

What is Science?

• Mathematics has both similarities and differences compared to other fields of science, and is sometimes included within a third, separate classification, called formal science. Mathematics is similar to other sciences because it is a rigorous, structured study (of topics such as quantity, structure, space, and change). It is different because of its method of arriving at its results. Mathematics as a whole is vital to the sciences — indeed major advances in mathematics have often led to major advances in other sciences. Certain aspects of mathematics are indispensable for the formation of hypotheses, theories and laws in discovering and describing how things work (natural sciences) and how people think and act (social sciences).

What is Science Not?

• Science as defined above is sometimes termed pure science to differentiate it from applied science, the application of research to human needs.

Is Psychology a “Collection”? Page 1of 2

• 1. Society for General Psychology2. Society for the Teaching of Psychology3. Experimental Psychology4. There is no Division 4 [more info]5. Evaluation, Measurement, and Statistics6. Behavioral Neuroscience and Comparative Psychology

7. Developmental Psychology8. Society for Personality and Social Psychology

9. Society for the Psychological Study of Social Issues (SPSSI)

10. Society for the Psychology of Aesthetics, Creativity and the Arts

11. There is no Division 11 [more info]12. Society of Clinical Psychology13. Society of Consulting Psychology14. Society for Industrial and Organizational Psychology

15. Educational Psychology

• 16. School Psychology17. Society of Counseling Psychology18. Psychologists in Public Service19. Society for Military Psychology20. Adult Development and Aging21. Applied Experimental and Engineering Psychology

22. Rehabilitation Psychology23. Society for Consumer Psychology24. Society for Theoretical and Philosophical Psychology

25. Behavior Analysis26. Society for the History of Psychology27. Society for Community Research and Action: Division of Community Psychology

28. Psychopharmacology and Substance Abuse

29. Psychotherapy30. Society of Psychological Hypnosis

Is Psychology a “Collection”? Page 2 of 2

• 31. State, Provincial, and Territorial Psychological Association Affairs

32. Humanistic Psychology33. Mental Retardation and Developmental Disabilities

34. Population and Environmental Psychology

35. Society for the Psychology of Women36. Psychology of Religion37. Child, Youth, and Family Services38. Health Psychology39. Psychoanalysis40. Clinical Neuropsychology41. American Psychology-Law Society42. Psychologists in Independent Practice43. Family Psychology

• 44. Society for the Psychological Study of Lesbian, Gay, and Bisexual Issues

45. Society for the Psychological Study of Ethnic Minority Issues

46. Media Psychology47. Exercise and Sport Psychology48. Society for the Study of Peace, Conflict, and Violence: Peace Psychology Division

49. Group Psychology and Group Psychotherapy

50. Addictions51. Society for the Psychological Study of Men and Masculinity52. International Psychology53. Society of Clinical Child and Adolescent Psychology54. Society of Pediatric Psychology55. American Society for the Advancement of Pharmacotherapy56. Trauma Psychology

Is there a Unifying Concept?

A. Must there be one?

B. Can we identify one?

Psychology My Definition

• The study of how Life acquires, processes, and acts on information acquired from the environment.

• Where “environment” includes external and internal physical and informational space.

Why do we need to answer this Question?

1. It forms the basis of our “paradigm”.

2. It defines the boundaries of our thinking.

3. It tells us what is important and…

4. It tells us what is unimportant.

Why do we need to answer this Question?

1. To perform an “experiment” we must know the scope of our investigation.

2. It tells us what we are looking for.

3. It tells us where to look.

4. It tells us about how we look for information.

5. It tells us who to use as subjects.

6. It may even tell us when to look.

Experiment - definitions

• the act of conducting a controlled test or investigation • the testing of an idea; "it was an experiment in living";

"not all experimentation is done in laboratories" • to conduct a test or investigation; "We are experimenting

with the new drug in order to fight this disease" • A series of trials or tests that are done to support or

disprove a hypothesis. • In the scientific method, an experiment is a set of actions

and observations, performed to verify or falsify a hypothesis or research a causal relationship between phenomena. The experiment is a cornerstone in empirical approach to knowledge.

Paradigm a. la. Kuhn

• The Structure of Scientific Revolutions, written as a graduate student in theoretical physics at Harvard.

• Sold some one million copies in 16 languages • Required reading in courses dealing with education,

history, psychology, research, and, of course, history and philosophy of science.

• Generated a good deal of controversy, and many of Kuhn's ideas have been powerfully challenged (see Weinberg link below).

http://www.des.emory.edu/mfp/Kuhnsnap.html

Paradigm Defined• Kuhn argued that science is not a steady, cumulative acquisition of knowledge.

Instead, science is "a series of peaceful interludes punctuated by intellectually violent revolutions" [Nicholas Wade, writing for Science], which he described as "the tradition-shattering complements to the tradition-bound activity of normal science." After such revolutions, "one conceptual world view is replaced by another" [Wade].

• Kuhn was responsible for popularizing the term paradigm, which he described as essentially a collection of beliefs shared by scientists, a set of agreements about how problems are to be understood.

• Paradigms are essential to scientific inquiry, for "no natural history can be interpreted in the absence of at least some implicit body of intertwined theoretical and methodological belief that permits selection, evaluation, and criticism."

• A paradigm guides the research efforts of scientific communities, and it is this criterion that most clearly identifies a field as a science. The typical developmental pattern of a mature science is the successive transition from one paradigm to another through a process of revolution. When a paradigm shift takes place, "a scientist's world is qualitatively transformed [and] quantitatively enriched by fundamental novelties of either fact or theory."

http://www.des.emory.edu/mfp/Kuhnsnap.html

Complexity

• Do dah…

So, how does all this philosophy help us with Experimental Design?

• We know we are interested – in living things– That interact with their internal & external environment

• Responds to an ‘articulatable’ question• The question domain must be within

– Our discipline– Our expertise

• Must mesh with existing body of knowledge• We must control or eliminate complexity

Parts and Pieces

• Understanding the real question to be answered– Customer/Client relations

• Methods – Variables– Control– Statistical requirements– Task– Environment

• Subject Selection– Ideal requirements– Real world limitations

• Previous work• Resources• Organizational

• Limits/prejudices• Traditions

• Actual Study Factors• Reporting • Time and Timing