Asking Research Questions

Deductive, Inductive, and non-theory driven research

Some TerminologyPage 18 of Course Packet

• Independent Variable (IV)-variable that the research intentionally manipulates in order to observe its effect on the DV.

• Dependent Variable (DV)- measure of behavior used by the researcher t0 assess the effects (if any) of the IV.

• (example: Effects of Caffeine on Fine Motor Skills)

• Internal Validity- the degree to which differences in performance (the dependent variable) can be attributed unambiguously to an effect of the independent variable. (aka confounds or “threats to internal validity”)

• External Validity- the extent to which the results of a particular research study can be generalized to different populations, settings, and conditions.

• Deduction (to deduce) - to derive as a conclusion from something known or assumed (to go from a general statement or theory to specific predictions/observations)

• Induction- to assert or establish on the basis of observation of particular (specific) facts (to go from specific observations to more general theory or statement)

• Theory-an explanation, usually in general terms.

• Hypothesis/hypotheses- a specific, testable statement, often a prediction about what you expect to happen in your study.

• A theory explains events in general terms, while a hypothesis makes a specific statement about a specified set of circumstances.

Example: Theory/hypothesis• “Theory”: Caffeine will negatively affect a

person’s ability to perform fine motor skills.

• “Hypothesis”: People will produce more errors on a mirror drawing task as the number of cups of coffee they drink increases.

• You use deduction when you derive a specific hypothesis from a more general theory.

• You use induction when you take a set of specific findings and produce a more general explanation (a “theory”).

Theory Driven Research: Deductive & Inductive Research

ProgramsPage 19 of Course Packet

Theories serve two purposes in research:

• They guide scientific research by suggesting research hypotheses. (Deductive Research)

• They organize empirical knowledge. (Inductive Research)

These two purposes lead to two different types of research (deductive and inductive), both driven by theories.

• In Deductive research, the research uses already established theories to deduce a specific and testable hypothesis of the form

“I expect this will happen if……” (Deductive hypothesis)

• In Inductive research, the research gathers many specific findings (usually though performing multiple studies) and then uses these specific findings to create a more general explanation (a theory).

• The hypothesis is of the form: “I wonder what will happen if….” (Inductive

hypothesis)

The Cyclical Nature of Theory Driven Research

Page 20 of Course Packet

Step1: Finding an interesting topic

• Intro Psych text• Talk to others doing research in area of

interest• Take a course, attend seminars or

lectures• Do a literature search and read/explore

what is known about the topic.

Graham Wallas (1858-1932)1926 The Art of Thought

Four stages of the scientific process:1) Preparation2) Incubation3) Illumination4) VerificationStages 1-3 would all be part of the Step 1 in

the process of theory-driven research.

Step 2: Developing a Testable Hypothesis (review)

Hypotheses can be of two sorts: Deductive and Inductive

• Deductive Hypotheses are the way in which theories guide research (Form: “I expect this will happen if…”)

• while Inductive Hypotheses are the way in which theories organize empirical knowledge (Form: “I wonder what will happen if…”)

• A hypothesis cannot contain vague concepts such as “mentally disturbed” or “intelligence”. (need operational definitions)

• A hypothesis cannot be circular.

• A hypothesis is untestable if it appeals to ideas or forces that are not recognized by science (unobservable forces)

Step 3: Selecting a design and evaluating ethics

• Different designs map onto the different goals of a piece of research. (description, prediction, etc.). Pick a design that fits your goal.

• Identify a target population and a sampling technique.

• Perform a formal evaluation for ethical issues via review boards (IRB or IACUC). Must be done before ANY data are gathered, even “pilot” data!

Step 4: Implement study in a way that achieves unambiguous results

• Avoid “threats to internal validity”.

• Control some variables and yet strive for high “external validity”.

Step 5:Collect and Summarize Data

Use descriptive statistics to summarize and understand data.

• Measures of Central Tendency: mean, median, mode.

• Measures of variability: range, variance, standard deviation.

Step 6: Draw conclusions using Inferential Statistics

Null Hypothesis Significance Testing (NHST)• Parametric statistics such as Student’s t-test or

Analysis of Variance (ANOVA)

• Non-parametric statistics such as Chi-square or Mann-Whitney U test

Step 7: Reject, Modify, Support

Based on your findings, you can choose one of three options:

• Reject your hypothesis showing a lack of support for your original theory or idea.

• Modify your original theory or idea based on your findings.

• Support your original theory or idea based on your findings.

ExampleStep 1: topic- “Stress causes illness” (general

statement)Step 2: Specific hypothesis- (thru operational

definition)- “I expect I will see an increase in visits to UHS during exam week.” (Deductive hypothesis)

Step 3-6: ethics approval, design choice, summarize/analyze results. Find increase in viral illnesses during exam week.

Step 7: Modify- Stress increases Viral illness

Non-theoretical Research (Radical Behaviorism)

• When you run into something interesting, drop everything and study it.

• Some ways of doing research are easier than others

• Apparatuses sometimes breakdownTheories are not necessary and can get in the way

of good research. Seek only to describe the functional relationships between/amongst variables

Non-theory driven researchB.F. Skinner, Radical Behaviorism

Goals of Scientific ResearchPages 40-49

1) Description: events and their relationships are defined classified, cataloged.

• Examples: DSM-IV TR 2000(diagnostic statistical manual of mental disorders, IV ed. TR 2000)

• Pace of Life Study (Levine 1990)

Pace of Life (Levine 1990) results

2) Prediction (correlation): occurs when measures vary together (co-vary) in a consistent way.

• Examples: GRE scores/undergraduate GPA as predictors of success in a graduate school environment.

 • Ambady & Rosenthal (1993)

3) Explanation: (causal inference) requires three conditions:

• co-variation of events-when one changes, the other changes in a consistent way.

• time-order relationship- one event always precedes the other. Antecedent-consequent.

• elimination of plausible alternative causes- eliminate all “threats to internal validity”

“True Experimental Design”

4) Application: research designed to solve a problem, applied research

Quasi-experimental and Applied Behavior Analysis