Principles of Science and Research Methods

• Science is the systematic study of the physical and natural world involving observation and experimentation, emphasizing empiricism.

Scientific Process

• A theory leads to research questions, which inform the research design and hypothesis.
• Data is collected and analyzed based on the hypothesis, feeding back into the cycle.

Good Scientific Theories

• Supported by data, falsifiable, parsimonious, and supported with evidence.

Availability Heuristic

• The belief that what is most frequently seen is most easily believed.

Research Variables

• Demographic: gender.
• Treatment: medical.
• Experimental: social.
• Dispositions: personality/intelligence.

Types of Research

• Quantitative (numbers) vs. Qualitative (themes/feelings).
• Experimental, quasi-experimental (comparing two settings).
• Psychometrics (statistical questions).
• Correlational, complex (parabolic vs. moderation).

Zimbardo Study

• The study was shut down after 6 days due to ethical concerns, influenced by Zimbardo's girlfriend.

Independent Variables

• Cause and effect, groups, characteristics of individuals or environments; manipulated.

Dependent Variables

• The effect of cause and effect, detecting differences.
• One IV for multiple DVs or multiple IVs for one DV.

Belmont Report

• Formal ethics guidelines developed in 1976 to guide researchers.

Belmont Report Principles

• Respect for persons (autonomy), beneficence, and justice.

Principle of Respect for Persons

• Research participants should freely decide to participate with informed consent, without coercion, and with debriefing afterward.

Principle of Beneficence

• Risk-benefit analysis, minimizing physical harm and stress, ensuring anonymity and confidentiality.

Principle of Justice

• Fairness in receiving study benefits and bearing risks.

The 3 R's

• Refinement, reduction (reducing animal use), and replacement (using software to reduce animal numbers).
• Ian Cook reviews animal studies.

Tuskegee Syphilis Study Ethical Violations

• Participants were not treated respectfully, lacked informed consent, were not informed about cures, and felt coerced.
• Participants were harmed and targeted as a disadvantaged group.

Milgram Obedience Study Ethical Violations

• Participants suffered long-lasting psychological effects.
• Researchers must balance ethical considerations with the value of the research.

IRB

• Institutional Review Board.

Deception in Research

• Omission: withholding study details.
• Commission: lying to participants.

Research Misconduct

• Data fabrication: inventing data.
• Data falsification: deleting or influencing data.
• Plagiarism.

Using PsychINFO

• Use "AND" between terms to narrow searches.
• Example: "Gender AND Fairness" reduces the number of articles.

Psychological Measures

• Self-report: questionnaires or interviews.
• Observational: recording behaviors.
• Physiological: recording biological data.

Operational Variable

• How a variable will be measured or manipulated.

Operationalizing Depression/Academic Performance

• Define the construct (conceptual variable) and create an operational definition.

Categorical Variables

• Levels are qualitatively distinct categories (nominal).

Quantitative Variables

• Variables coded with meaningful numbers.
• Ordinal scale: rank order.
• Interval scale: equal distances, no true zero.
• Ratio scale: equal intervals, true zero.

Validity

• The accuracy of a measure; a measure can be reliable but not valid.

Face Validity

• It appears to measure what it intends to measure.

Content Validity

• The measure includes all the necessary parts based on a theory.

Criterion Validity

• The measure relates to a concrete outcome it should be related to.

Reliability

• Consistency and correlation within a measure.
• Necessary but not sufficient for validity.

Test Reliability

• Consistent scores each time the measure is used.

Interrater Reliability

• Consistent scores regardless of who does the measuring.

Measuring Depression

• Examples: negative comments, Beck Depression Inventory, serotonin levels.

Internal Reliability

• Participants provide consistent responses regardless of question phrasing.

Types of Reliability

• Interrater, internal, test-retest.

Types of Validity

• Face, content, criterion.

Non-Random Sample

• Some population elements have no chance of selection, or the probability is unknown.

Random Sample

• All members of the population are equally likely to be chosen.

Non-Probability Sampling

• Elements have an unknown chance of being selected.

Probability Sampling

• Every population member has an equal chance of being selected.

Randomization and Validity

• Non-random (convenience) samples threaten external validity.
• Observational research should have high construct validity.

Probability Sampling Types

• Cluster sampling: randomly selecting clusters within a population.
• Multistage sampling: random samples are collected (clusters, then individuals).
• Stratified random sampling: selecting specific demographic categories.
• Oversampling: over-representing one or more groups in stratified sampling.
• Systematic sampling: using a system to choose the group.

Non-Probability Sampling Techniques

• Convenience sampling: easy-to-access samples.
• Purposive sampling: studying specific types of people.
• Snowball sampling: participants recommend other participants.
• Quota sampling: setting target numbers for categories and using non-random sampling to fill the quota.

Assigning Groups

• Random assignment: used in experiments to place participants into treatment or comparison groups.

Overview of science as a systematic study involving observation, experimentation, and empiricism. Covers the scientific process, characteristics of good scientific theories, research variables, and various types of research methods including quantitative, qualitative, and experimental designs.