AP Psychology: Research Methods Notes
Research Methods Key Terms
Types of Psychological Research
- Quantitative research: Research that uses operational measurements and statistical techniques to reach conclusions on the basis of numerical data, such as correlational studies and experiments.
- Qualitative research: Research that does not rely on numerical representations of data, such as naturalistic observations, unstructured interviews, and case studies.
- Correlation coefficient: A number (symbolized by r) between −1 and +1, which represents the strength and direction of the correlation between two variables. The closer the coefficient is to −1 or +1, the stronger the correlation between the variables.
- Positive correlation: An r value above 0, which indicates that two variables have a direct relationship: when one variable increases, the other also increases.
- Negative correlation: An r value below 0, which indicates that two variables have an inverse relationship: when one variable increases, the other decreases.
- Naturalistic observation: A research method, typically qualitative in nature and usually covert and undisclosed, that attempts to document behavior as it spontaneously occurs in a real world setting.
- Structured observation: A type of observational research typically conducted in a laboratory setting, where the researcher can control some aspects of the environment.
- Coding: The classification of behaviors into discrete categories, used especially in structured observations to achieve a level of consistency in recording and describing observations.
- Inter-rater reliability: A statistical measure of the degree of agreement between different codings of the same phenomena.
- Participant observation: A mostly qualitative research method in which the researcher becomes a member of a studied group, either overtly or covertly.
- Hawthorne effect: A phenomenon in which research subjects tend to alter their behavior in response to knowledge of being observed.
- Longitudinal study: A research design that examines how individuals develop by studying the same sample over a long period of time.
- Cross-sectional study: A research design conducted at a single point in time, comparing groups of differing ages to arrive at conclusions about development.
- Case study: A research design involving an in-depth and detailed examination of a single subject, or case, usually an individual or a small group.
- Survey: A mostly quantitative research method involving a list of questions filled out by a group of people to assess attitudes or opinions.
- Nonresponse bias: A distortion of data that can occur in surveys with a low response rate.
- Surveyor bias: A distortion of data that can occur when survey questions are written in a way that prompts respondents to answer a certain way.
- Experiments: Deliberately designed procedures used to test research hypotheses.
- Hypothesis: A proposed, testable explanation for a phenomenon, often constructed in the form of a statement about the relationship between two or more variables.
- Controlled experiment: A research design for testing a causal hypothesis, in which all aspects of the study are deliberately controlled and only independent variables are manipulated to isolate their effects on dependent variables.
- Field experiment: Experiments conducted out in the real world, with fewer controls than would be found in a lab.
