Psychology 2e: Chapter 2

deductive reasoning

results are predicted based on a general premise

inductive reasoning

conclusions are drawn from observations

Theory

well-developed set of ideas that propose an explanation for observed phenomena

Hypothesis

a tentative, testable statement or prediction about what has been observed

Approaches to Research

Clinical or case studies; Naturalistic Observation; Survey; Archival Research; Longitudinal and Cross-Sectional Research

clinical or case studies

Focus on one individual. The studied individual is typically in a extreme or unique psychological circumstance that differentiates them for the general public. Also for a lot of insight into a case. Difficult to generalize results to the larger population.

observer bias

when observations may be skewed to align with observer expectations

Jane Goodall

made a career of conducting naturalistic observations of chimpanzee behavior

archival research

Uses past records or data sets to answer various research questions, or to search for interesting patterns or relationships

Cross-sectional Research

compares multiple segments of a population at a single time

Longitudinal

Studies in which the same group of individuals is surveyed or measured repeatedly over an extended period of time.

attrition

reduction in number of research participants as some drop out of the study over time

Correlation

relationship between two variables

correlation coefficient

number from -1 to +1, indicating the strength and direction of the relationship between variables, and usually represented by r

positive coorelation

Two variables change in the same direction, both becoming either larger or smaller.

negative coorelation

Two variables change in different directions, with one becoming larger as the other becoming smaller, a negative correlation is not the same thing as no correlation

cause-and-effect relationship

changes in one variable cause the changes in the other variable; can be determined only through an experimental research design

confounding variable

unanticipated outside factor that affects both variables of interest, often giving the false impression that changes in one variable causes changes in the other variable, when, in actuality, the outside factor causes changes in both variables

illusory correlation

seeing relationships between two things when in reality no such relationship exists

confirmation bias

tendency to ignore evidence that disproves ideas or beliefs.

experimental group

The participants that experience the manipulated variable (group designed to answer the research question).

control group

Participants that do not experience the manipulated variable.

operational definition

description of what actions and operations will be used to measure the dependent variables and manipulate the independent variables

Experimenter bias

researcher expectations skew the results of the study

Participant bias

participant expectations skew the results of the study.

Single-blind study

experiment in which the researcher knows which participants are in the experimental group and which are in the control group

Double-blind study

experiment in which both the researchers and the participants are blind to group assignments

placebo effect

people's expectations or beliefs influencing or determining their experience in a given situation

independent variable

Variable that is influenced/controlled by the experimenter. Ideally this should be the only important difference between the experimental and control group.

dependent variable

variable that the researcher measures to see how much effect the independent variable had

Participants

subjects of psychological research

Sample

subset of individuals selected from the larger population

Population

Overall group of individuals that the researcher is interested in.

Random Sample

subset of a larger population in which every member of the population has an equal chance of being selected

random assignment

method of experimental group assignment in which all participants have an equal chance of being assigned to either group

Institutional Animal Care and Use Committee (IACUC)

Committee of administrators, scientists, veterinarians, and community members that reviews proposals for research involving non-human animals.

deception research

purposely misleading experiment participants in order to maintain the integrity of the experiment

Debriefing

when an experiment involved deception, participants are told complete and truthful information about the experiment at its conclusion

Institutional Review Board (IRB)

committee of administrators, scientists, and community members that reviews proposals for research involving human participants

Statistical analysis

determines how likely any difference between experimental groups is due to chance