The Research Enterprise

1. The Research Enterprise

2. The Research Enterprise in SLP/A • Only 1% are full-time researchers • Classes, lectures, textbooks • information is gained through the eyes of the professor; eyes of the authors • therefore, need to develop own critical decisions about research by reading original sources • Letters to the Editor is another source for facilitating development of critical decision making

3. Clinicians need to have enough familiarity with research to judge whether the claims are reasonable and to determine just how closely the proposed clinical procedures adhere to the research methods and the underlying theory. Informed clinicians need not be sophisticated researchers, but they should have had first-hand experience with research during their graduate education to help them understand the limitations and the possibilities of research and the decisions that face researchers at so many turns in the conduct of a study.Siegel (1996)

4. Research-Practice Relationship (Logemann, 2000) There are comments that I find disturbing, but luckily, hear only occasionally. The clinician, for instance, who says, “I don’t read journals because they’re all research and that’s over my head.” Or the researcher who says, “It’s unimportant whether a clinician reads my research or not, because it’s really for other researchers.”

5. Myths about Published Research • “You must be a statistician to read the literature” • “If it is in print, it must be good” • “The more difficult to read, the more scholarly an article must be”

6. The Method of Science (Kerlinger & Lee, 2000) Scientific research is a systematic, controlled, empirical, amoral, public, and critical investigation of natural phenomena. It is guided by theory and hypotheses about the presumed relations among such phenomena. • Systematic and controlled imply that the scientific investigation is tightly disciplined and conducted in a manner that methodically rules out alternative explanations of a particular finding.

7. Empiricism vs Rationalism Scientific research depends on a complex interplay of two distinct lines of inquiry: empiricism and rationalism These are two different philosophies that guide research

8. Empiricism assumes that knowledge must be gained through experience relies on inductive reasoning which uses evidence from specific cases to make inferences about general principles Rationalism assumes that knowledge must be gained through the exercise of logical thought relies on deductive reasoning which uses general principles to make inferences about specific cases Two Modes of Inquiry in Behavioral Science

9. Uses evidence from particular cases to make inferences about general principles (specific cases -> general principles) Experiments first, then theories emerge inductively from data Uses general principles to make inferences about specific cases (general principles -> specific cases) Theory first, then test deductively by experimentation Empiricism vs Rationalism (con’t)

10. Explanations based on evidence gained from observations of phenomena, and critical evaluations of the accuracy of observations is necessary before the observations can be accepted into the realm of knowledge Concrete, empirical, experiential observations Explanations based on logical criticism of propositions which are necessary for the acceptance of explanations into the realm of knowledge Abstract, formal, analytical endeavors Empiricism vs Rationalism (con’t)

11. The Research Enterprise in CDIS: Scientific research directed toward “basic research” or “applied research” Scientific Research Basic ResearchApplied Research - development of a - used to solve some knowledge base some social or economic problem

12. Types of Research HistoricalDescriptiveExperimental Uses documentary Examines group Examinescausa- evidence to identify differences, trends tion through patterns or relationships observation of among variables the effects of the using laboratory manipulation of measurements certain variables on other variables under controlled conditions

13. Induction empiricism specific case general principles bottom-up knowledge gained through experience Skinner Deduction rationalism general principles specific cases top-down knowledge gained through logical thought Chomsky Two Categories of Theories (Philosophies)

14. Steps in Research 1. Statement of the Problem 2. Method of investigation a. Subjects/participants b. Materials c. Procedures 3. Results of investigation 4. Conclusions

15. Variables in Empirical Research • Variables are measurable quantities that vary or change under different circumstances • can be classified in one of 3 ways 1. Independent vs Dependent variables 2. Active vs Attribute variables 3. Continuous vs Categorical variables

16. Independent Variables IV is the presumed cause of the DV is the antecedent CAUSES change in the behavior you manipulate the IV Dependent Variables DV is the presumed effect is the consequent is the behavior that has CHANGED you measure the change in the DV Independent vs Dependent Variables

17. Active Variable can be manipulated is the IV Attribute Variable is an existing, non-changing variable (e.g., I.Q., age, gender) usually the DV, but can be an IV in descriptive research Active vs Attribute Variables

18. Continuous Variable can be measured along a continuum that reflects a rank ordering of values of the variable (e.g., frequency of stuttering, mild-severe) Categorical Variable cannot be measured along a continuum the values of the variable can only be categorized or named (e.g., Stutterer vs Non-stutterer) Continuous vs Categorical Variables

19. Experimental Research Used to investigate cause-and-effect relationships among variables 4 characteristics of experimental research: • starts with a purpose, question, or hypothesis • CONTROLS events and therefore observes CHANGES in behavior • is repeatable • can measure effects on certain variables by manipulating other variables • must be cautious to control “extraneous variables”

20. Classification of Research Classification of experimental research on basis of: 1. number of IVs 2. number of values of the IVs

21. Bivalent Experiments • Experimenter studies the effect of 2 values of one IV on the DV • The IV is manipulated so that only 2 values of the IV is presented to the Ss • experimenter selects only two of many values that fall along a continuum of the IV to be manipulated • for categorical variables, only two categories of the IV are selected to be manipulated

22. Multivalent Experiments • Experimenter studies the effects of several values of the IV on the DV • at least 3 values of the IV are presented to the Ss • gives a broader picture of the relationship between the IV and DV because experimenter samples the range of possible values of the IV more thoroughly • therefore can identify a curvilinear function

23. Multivalent Experiments (con’t) EX: Ho: increases in the intensity of masking noise will cause a decrease in stuttering frequency • IV: masking noise • LEVELS: quiet, 10, 50, 90dB • DV: stuttering frequency

24. Parametric Experiments • Researcher studies the simultaneous effects of more than one IV on the DV • the second IV is called the parameter • can examine two main effects on the DV as well as an interaction between the two IV in causing changes in the DV • EX: effect of distance and syllable word pattern on lipreading ability.

25. Descriptive Research Does not lead to a cause-and-effect identification between IV and DV 6 Types of descriptive research: • comparative research • developmental research • correlational research • survey research • case study • retrospective research

26. Comparative Research • Measures behavior of two or more types of subjects in order to identify similarities and differences between them • EX: children with and without PD to examine syntactic performance

27. Developmental Research • Measures changes over time in the behavior or characteristics of subjects • 3 types of developmental research • cross-sectional • longitudinal • semi-longitudinal

28. Correlational Research • Studies the relationship among two or more variables by examining the degree to which changes in one variable correspond with or can be predicted from variations in another • EX: relationship between syntax and phonology. As syntactic complexity increases, what happens in phonology?

29. Survey Research • Examines conditions, practices, or attitudes through questionnaires, interviews, or a combination of the two

30. Case Study • Examines an individual in detail rather than as part of a group

31. Retrospective Research • Examines data already on file formulating a research problem