Glossary

When a participants name and other personally identifiable information is not collected at all.

Stands for the APA’s Ethical Principles of Psychologists and Code of Conduct. It was first published in 1953 and includes about 150 specific ethical standards that psychologists and their students are expected to follow.

A persons right to make their own choices and take their own actions free from coercion.

Measures in which some other aspect of participants’ behavior is observed and recorded.

Underscores the importance of maximizing the benefits of research while minimizing harms to participants and society.

An acronym that stands for “brief,” “relevant,” “unambiguous,” “specific,” and “objective,” which is used to create effective questionnaire items that are brief and to the point.

An effect of being tested in one condition on participants’ behavior in later conditions.

An in-depth examination of an individual.

A type of probability sampling in which larger clusters of individuals are randomly sampled and then individuals within each cluster are randomly sampled.

Differences between the groups may reflect the generation that people come from rather than a direct effect of age.

A method in which an equal number of participants complete each possible order of conditions. 

Describes the behaviors and internal processes that make up a psychological construct, along with how it relates to other variables.

A helper who pretended to be a real participant in a study.

An agreement not to disclose participants’ personal information without their consent or some appropriate legal authorization.

A specific type of extraneous variable that systematically varies along with the variables under investigation and therefore provides an alternative explanation for the results.

The process of obtaining informed consent by having the participants read and sign the form.

Unintended influences on respondents’ answers because they are not related to the content of the item but to the context in which the item appears.

Holding extraneous variables constant in order to separate the effect of the independent variable from the effect of the extraneous variables.

When psychologists use multiple operational definitions of the same construct—either within a study or across studies.

Research that is non-experimental because it focuses on the statistical relationship between two variables but does not include the manipulation of an independent variable.

The extent to which people’s scores on a measure are correlated with other variables (known as criteria) that one would expect them to be correlated with.

Studies that involve comparing two or more pre-existing groups of people (e.g., children at different stages of development).

Studies in which researchers follow people in different age groups in a smaller period of time.

This is the process of informing research participants as soon as possible of the purpose of the study, revealing any deception, and correcting any other misconceptions they might have as a result of participating.

Misinforming participants about the purpose of a study, using confederates, using phony equipment like Milgram’s shock generator, and presenting participants with false feedback about their performance (e.g., telling them they did poorly on a test when they actually did well).

An ethics code that was created by the World Medical Council in 1964.

The variable the experimenter measures (it is the presumed effect).

Is used to sample extra respondents from particularly small subgroups—allowing valid conclusions to be drawn about those subgroups.

The branch of philosophy that is concerned with morality—what it means to behave morally and how people can achieve that goal.

Research on the effectiveness of normal educational activities, the use of standard psychological measures and surveys of a nonsensitive nature that are administered in a way that maintains confidentiality, and research using existing data from public sources.

When the experimenter’s expectations about how participants “should” behave in the experiment affect how the participants behave.

Refers to the degree to which we can generalize the findings to other circumstances or settings, like the real-world environment.

A complex statistical technique in which researchers study relationships among a large number of conceptually similar variables.

An effect where participants perform a task worse in later conditions because they become tired or bored.

Used in qualitative research which involves small groups of people who participate together in interviews focused on a particular topic or issue.

Researchers start with the data and develop a theory or an interpretation that is “grounded in” those data.

A research method that allows researchers to draw conclusions or infer about a population based on data from a sample.

This means that researchers obtain and document people’s agreement to participate in a study after having informed them of everything that might reasonably be expected to affect their decision.

The extent to which different observers are consistent in their judgments.

The consistency of people’s responses across the items on a multiple-item measure.

Refers to the degree to which we can confidently infer a causal relationship between variables.

A measurement that involves assigning scores using numerical scales in which intervals have the same interpretation throughout.

When the order in which the items are presented affects people’s responses.

The importance of conducting research in a way that distributes risks and benefits fairly across different groups at the societal level.

A study that is conducted in the laboratory environment.

Studies in which one group of people are followed over time as they age.

The average of a distribution of scores (symbolized M) where the sum of the scores are divided by the number of scores.

Is the assignment of scores to individuals so that the scores represent some characteristic of the individuals.

The midpoint of a distribution of scores in the sense that half the scores in the distribution are less than it and half are greater than it.

Research that combines both quantitative and qualitative approaches.

The most frequently occurring score in a distribution.

Involves measuring several variables (X1, X2, X3,…Xi), and using them to predict some outcome variable (Y).

When the participants and the situation studied are similar to those that the researchers want to generalize to and participants encounter every day.

A relationship in which higher scores on one variable tend to be associated with lower scores on the other.

A measurement used for categorical variables and involves assigning scores that are category labels.

A research that lacks the manipulation of an independent variable.

Occurs when the researcher cannot specify the probability that each member of the population will be selected for the sample.

Occurs when there is a systemic difference between survey non-responders from survey responders.

Research that is non-experimental because it focuses on recording systemic observations of behavior in a natural or laboratory setting without manipulating anything.

A treatment is implemented (or an independent variable is manipulated) and then a dependent variable is measured once after the treatment is implemented.

An experiment design in which the dependent variable is measured once before the treatment is implemented and once after it is implemented.

Simply ask a question and allow participants to answer in whatever way they choose.

An effect that occurs when participants' responses in the various conditions are affected by the order of conditions to which they were exposed.

A measurement that involves assigning scores so that they represent the rank order of the individuals.

A statistic that measures the strength of a correlation between quantitative variables.

Measures that involve recording any of a wide variety of physiological processes, including heart rate and blood pressure, galvanic skin response, hormone levels, and electrical activity and blood flow in the brain.

Is a small-scale study conducted to make sure that a new procedure works as planned.

A relationship in which higher scores on one variable tend to be associated with higher scores on the other.

An effect where participants perform a task better in later conditions because they have had a chance to practice it.

A way to minimize risks in a study and to identify and eliminate participants who are at high risk.

A persons right to decide what information about them is shared with others.

Occurs when the researcher can specify the probability that each member of the population will be selected for the sample.

Is used to select a sample in which the proportion of respondents in each of various subgroups matches the proportion in the population.

A detailed description of the research—that is reviewed by an independent committee.

Where the same mental process is used in both the laboratory and in the real world.

Research that begins with a less focused research question, collects large amounts of relatively “unfiltered” data from a relatively small number of individuals, describes data using nonstatistical techniques, such as grounded theory, thematic analysis, critical discourse analysis, or interpretative phenomenological analysis and aims to understand in detail the experience of the research participants.

Research that typically starts with a focused research question or hypothesis, collects a small amount of numerical data from a large number of individuals, describes the resulting data using statistical techniques, and draws general conclusions about some large population. 

A method in which the order of the conditions is randomly determined for each participant.

A measure of dispersion that measures the distance between the highest and lowest scores in a distribution.

An ordered set of responses that participants must choose from.

A measurement that involves assigning scores in such a way that there is a true zero point that represents the complete absence of the quantity.

Refers to the consistency of a measure.

Participants in a survey or study.

Occurs when a sample is selected in such a way that it is not representative of the entire population and therefore produces inaccurate results.

A list of all the members of the population from which to select the respondents.

Measures in which participants report on their own thoughts, feelings, and actions.

A form of non-probability sampling in which individuals choose to take part in the research on their own accord, without being approached by the researcher directly.

A probability sampling method in which each individual in the population has an equal probability of being selected for the sample.

A form of non-probability sampling in which existing research participants help recruit additional participants for the study.

A score that is derived by splitting the items into two sets and examining the relationship between the two sets of scores in order to assess the internal consistency of a measure.

Controlling potential third variables to rule out other plausible interpretations.

Concerns the proper statistical treatment of data and the soundness of the researchers’ statistical conclusions.

An effect that is unlikely due to random chance and therefore likely represents a real effect in the population.

A common alternative to simple random sampling in which the population is divided into different subgroups or “strata” (usually based on demographic characteristics) and then a random sample is taken from each “stratum.”

When a researcher makes careful observations of one or more specific behaviors in a particular setting that is more structured than the settings used in naturalistic or participant observation.

An established group of people who have agreed to be contacted about participating in research studies.

A quantitative and qualitative method with two important characteristics; variables are measured using self-reports and considerable attention is paid to the issue of sampling.

When researchers measure a construct that they assume to be consistent across time, then the scores they obtain should also be consistent across time.

Researchers become a part of the group they are studying and they disclose their true identity as researchers to the group under investigation.

The extent to which the scores from a measure represent the variable they are intended to.