Lecture 1 Notes — Research Methods (Descriptive, Correlational, Sampling)

Vocabulary flashcards covering key concepts from the lecture notes on replication, scientific self-correction, research types, sampling, and validity.

Replication

The repetition of a study or experiment to verify results; increases confidence when findings are reproduced; if results differ, prompts closer scrutiny.

Self-correcting science

Science is in a constant state of evolution and self-correcting; errors and bias are identified and conclusions are updated as new evidence emerges.

Descriptive research

Systematically observing and describing what is observed; answers what, when, where, and how; does not explain why (causes).

Correlational research

Investigates relationships between two variables; assesses whether they covary and how strongly (direction and strength); cannot infer causation.

Case study

In-depth study/investigation of one person or a very small group or event; advantages: captures rare/unique cases and deep understanding; disadvantages: limited generalizability.

Survey

A scientific investigation using questions or interviews to collect data from a sample; advantages: cheap, easy; disadvantages: potential bias or misreporting due to interviewer effects.

Random sampling

A sampling method where every member of the population has an equal chance of being selected; aims to produce a representative sample.

Simple random sampling

A basic form of random sampling where each individual has an equal probability of selection.

Stratified random sampling

Population divided into subgroups (strata) and samples drawn from each subgroup to ensure representation of key groups.

Population

The entire group of individuals or cases the researcher is interested in.

Sample

A subset of the population used to collect data and infer about the population.

Generalization

Extending findings from the sample to the population; depends on how representative the sample is; not always possible if sample is too small or atypical.

Correlation coefficient (r)

A statistic that measures the strength and direction of a linear relationship between two variables; ranges from -1 to +1; values near 0 indicate weak/no relationship; values closer to ±1 indicate stronger relationships.

Positive correlation

As one variable increases, the other tends to increase.

Negative correlation

As one variable increases, the other tends to decrease.

Bias (research bias)

Systematic errors in data collection or interpretation due to researchers' expectations or theories; can affect results; mitigated by procedures like multiple observers and technology.

Control variables

Variables kept constant to prevent them from affecting the outcome and to isolate the relationship between the main variables.

Ecological validity

The extent to which study findings generalize to real-world settings; higher when behavior observed in natural contexts.

Representative sample

A sample that accurately reflects the characteristics of the population from which it is drawn.