Overview
This lecture covers the main research methods in psychology, key steps in conducting scientific research, types of data analysis, and essential statistical concepts for ISC Grade 11, Unit Two.
Scientific Method in Psychology
- Psychology is an empirical, evidence-based science using systematic and objective approaches to study behavior.
- The scientific method involves assumptions, attitudes, and procedures guiding research.
- Research methods include experiments, case studies, surveys, observation, and longitudinal studies.
Research Methods
- Observation: Systematic watching and recording of behaviors; divided into controlled (lab settings, variables managed) and uncontrolled/naturalistic (field, variables uncontrolled).
- Merits: Eliminates response bias, studies nonverbal behavior, provides realistic data.
- Demerits: Observer bias, time-consuming, costly.
- Field Study: Data collected in natural environments, includes direct observation and interaction.
- Longitudinal Study: Follows the same group over time to track changes and establish cause-effect relationships.
- Cross-sectional Study: Collects data at one time from different groups; allows comparison but can't show changes over time.
- Case History Method: In-depth study of an individual or group, useful for rare cases but not generalizable.
- Survey: Gathers data from large groups through questions or interviews; time- and cost-efficient but subject to response bias.
Experimental Method
- Researcher manipulates an independent variable to see its effect on a dependent variable using control and experimental groups.
- Placebo effect: Changes resulting from participants believing they received treatment.
- Steps: Formulate problem, gather data, classify, hypothesize, test, verify, and predict.
Sampling in Research
- Sample: Subset of the population being studied.
- Population: Entire group a study aims to understand.
- Random sampling: Ensures every individual has an equal chance of selection.
- Representative sample: Accurately reflects the population, avoiding sampling bias.
Psychological Tests
- Used to assess behavior for decisions in diagnosis, career guidance, and recruitment.
- Types: IQ, personality, and aptitude tests.
- Characteristics: Standardized, objective, reliable, valid, and norm-referenced.
Ethical Concerns in Research
- Participation must be voluntary and informed.
- Participants should be debriefed and results shared.
- Data confidentiality is essential.
Statistics in Psychology
- Used to collect, organize, analyze, and present data (COAP).
- Descriptive statistics: Summarize data (mean, median, mode, range, standard deviation).
- Inferential statistics: Determine if group differences are significant using tests (e.g., t-test, ANOVA).
Key Terms & Definitions
- Empirical Science — Knowledge based on evidence and observation.
- Variable — Any factor that can change in a study.
- Sample — A selected group from the population for study.
- Population — The entire group relevant to a research question.
- Random Sampling — Each member of the population has an equal chance of selection.
- Reliability — Consistency of a test's results.
- Validity — Whether a test measures what it's supposed to measure.
- Mean — Average of a data set.
- Median — Middle value of an ordered data set.
- Mode — Most frequently occurring value.
- Range — Difference between highest and lowest values.
- Standard Deviation — Average distance of scores from the mean.
Action Items / Next Steps
- Review Unit One if not already done.
- Submit an example of a survey in the comments as requested.
- Revise key definitions, steps of the scientific method, and central statistical concepts for exams.