OpenStax Psychology 2e – Chapter 2 Research

Why is Research Important?

• Validates claims and ideas through study and testing.
• Scientific research is empirical, grounded in objective evidence.
• Psychology is a science, requiring research for verification and support.

Use of Research Information

• Critically evaluate claims by considering the expertise of the claimer, potential gains, justification of the claim based on evidence, and opinions of other researchers.

The Process of Scientific Research: Inductive vs Deductive Reasoning

• Deductive Reasoning: Predicts results based on a general premise.
  • Example: All living things need energy; ducks are living things; therefore, ducks need energy.
• Inductive Reasoning: Draws conclusions from observations.
  • Example: Seeing many fruits on trees and assuming all fruits grow on trees.
• Scientific Process:
  1. Scientists form theories/hypotheses through deductive reasoning.
  2. Hypotheses are tested through empirical observations, and scientists draw conclusions through inductive reasoning.
  3. Conclusions lead to new theories and hypotheses.

The Scientific Method

• Theory: A well-developed set of ideas explaining observed phenomena.
• Hypothesis: A testable statement predicting relationships between variables, often in an "if-then" format.
  • Must be falsifiable.

Approaches to Research

• Clinical or Case Studies: Focus on one individual, providing deep insights but may not generalize to the larger population.
• Naturalistic Observation: Observing behavior in its natural setting to eliminate performance anxiety. Clear criteria help avoid observer bias.
• Surveys: Collect data through questions delivered via paper, electronically, or verbally from a sample of a larger population.
• Archival Research: Uses past records or datasets to find patterns or answer research questions.
• Longitudinal Research: Studies the same group repeatedly over time.
• Cross-Sectional Research: Compares multiple population segments at a single time.
  • Attrition: Reduction in participants over time.

Correlational Research

• Correlation: Relationship between variables; when one changes, so does the other.
• Correlation Coefficient (r): From -1 to +1, indicating strength and direction.
  • Positive Correlation: Variables increase or decrease together.
  • Negative Correlation: One variable increases as the other decreases.
• Correlation does not indicate causation.
  • Confounding variable: An outside factor affecting both variables, creating a false impression of causation.
• Illusory Correlations: Perceiving relationships that don't exist.
  • Confirmation bias: Ignoring evidence that disproves beliefs.

Causality: Conducting Experiments & Using the Data

• Experiments are needed to establish cause-and-effect relationships.
• Experimental Hypothesis: Formulated through observation or previous research.

Designing an Experiment

• Experimental Group: Receives the manipulated variable.
• Control Group: Does not receive the manipulated variable, serving as a comparison.
• Operational Definition: Describes how variables are measured and manipulated.
• Avoiding Bias:
  • Experimenter bias: Researcher expectations skew results.
  • Participant bias: Participant expectations skew results.
  • Single-blind Study: Participants are unaware of group assignments.
  • Double-blind Study: Both participants and researchers are unaware of group assignments.
  • Placebo Effect: Expectations influence outcomes; control groups receive placebo treatments.

Variables

• Independent Variable: Controlled/manipulated by the experimenter.
• Dependent Variable: Measured by the researcher to assess the impact of the independent variable.

Selecting Participants

• Sample: Subset from a larger population.
• Population: The overall group of interest.
• Random Sample: Each member has an equal chance of selection, increasing representativeness.

Assigning Participants to Groups: Experimental or Control

• Random Assignment: Participants have an equal chance of being in either group.
  • Prevents systematic differences between groups, crucial for determining cause-and-effect relationships.

Issues to Consider Manipulating Variables

• Quasi-experimental: When the independent variable cannot be manipulated or participants cannot be randomly assigned (e.g., effect of sex on spatial memory).
  • Cause-and-effect relationships cannot be determined in these designs.
• Ethics: Some research questions cannot be answered through experiments due to ethical concerns (e.g., the effect of childhood abuse).

Interpreting Experimental Findings

• Statistical Analysis: Determines if differences between groups are due to chance.
• Significance: Results are significant if the odds of occurring by chance are 5% or less.

Reporting Findings

• Research is reported in peer-reviewed scientific journals.
• Peer-review: Experts provide feedback on the study's quality.
• Replication: Determines reliability and expands on original findings.

Bad Science & Retraction: The Vaccine-Autism Myth

• Some studies claiming a link between vaccines and autism have been retracted due to flawed research and financial interests.

Reliability and Validity

• Reliability: Consistency and reproducibility of results.
  • Inter-rater reliability: Agreement among observers.
• Validity: Accuracy of measuring what is intended.
  • A valid measure is always reliable, but a reliable measure isn't always valid.

Ethics: Research Involving Human Participants

• Institutional Review Board (IRB): Reviews research proposals involving human participants.
• Informed Consent: Participants are informed about risks, implications, and their right to withdraw; data confidentiality is assured.

Deception

• Deception: Misleading participants to maintain experiment integrity, as long as it's not harmful.
• Debriefing: Providing complete information about the experiment after participation.
• Ethical guidelines prevent harmful studies like the Tuskegee Syphilis study.

Ethics: Research Involving Animal Subjects

• Institutional Animal Care and Use Committee (IACUC): Reviews research involving animals.
• Animals are used when research would be unethical with humans, minimizing pain and distress.