Non-experimental and Quasi-experimental Research

A research design where the independent variable (IV) is manipulated, but participants are not randomly assigned to groups, leading to potential confounding variables.

A research design where a single group of participants is measured before and after a treatment is implemented. This design is vulnerable to external explanations for changes in the dependent variable.

A research design that involves multiple measurements of a dependent variable over time, with a treatment implemented at some point. This helps identify trends and the impact of the treatment.

A research design where two or more groups of participants are compared without random assignment, making it harder to isolate the effect of the independent variable.

A quasi-experimental design involving two groups: one exposed to a treatment and one not, measured only after the treatment. It's weaker than designs with pretests.

A type of artifact that emerges when an association between two variables can be explained away by the presence of a third variable that is related to each of the other two.

The strength of the relationship between two variables in a population.

The variable that is manipulated or changed by the researcher in an experiment.

The variable that is measured in an experiment.

A group in an experiment that does not receive the treatment or intervention being studied.

A method used to place participants into experimental groups in an unbiased way.

A type of artifact that occurs when an extreme data point is included, distorting the perception of a trend.

A type of artifact that occurs when the data collected is artificially restricted, failing to reflect the full range of possibilities.

The tendency for extreme scores on a variable to regress towards the mean when measured again.

A type of artifact that represents a curved relationship between two variables instead of a straight line.

A type of research design where an intervention is introduced to some groups, but not others (control). Measurements are taken before and after the intervention in both groups.

A design that uses two groups, with one receiving a treatment and the other acting as a control. Both groups are assessed before and after the treatment. Later, the treatment group becomes the control, and the control group receives the treatment.

Similar to switching replication, but the first group stops receiving the treatment and the second group starts.

A technique for observing behavior without direct interference. Can be either disguised (hidden) or undisguised (open).

When participants act differently due to awareness of being observed.

Active participation in a group or event while observing behaviors. Researchers become part of the setting being studied.

Observing behaviors with predefined parameters set by the researcher. May or may not happen in a natural environment.

Manipulating a variable in a natural setting before making observations. Similar to a natural experiment.

An organized system for identifying and classifying observable behaviors with standardized categories and examples. Researchers must ensure inter-rater reliability.

A type of coding system where researchers identify keywords, phrases, or ideas occurring within a text corpus.

A type of research design with two or more independent variables. Allows researchers to understand the effects of each variable and their combined effect.

Each independent variable in a factorial design. Requires at least two levels or conditions.

The interaction effect occurs when the effect of one independent variable on the outcome depends on the level of another independent variable.

The effect of a single independent variable on the outcome, ignoring other variables.

An in-depth, qualitative investigation of a single individual or group. Often used for studying unique cases or rare conditions.

An extraneous variable that influences the dependent variable, making it harder to see the relationship between the independent variable and the dependent variable. Think of it as background noise that makes it difficult to hear the signal of the study.

A research design where each participant is only assigned to one experimental condition. This means that each person only experiences one version of the treatment.

A research design where all participants are tested in every experimental condition, but the order of these conditions is randomized. This allows researchers to control for order effects and treat each participant as their own control.

Any confounding factor that arises due to the order in which conditions are presented. This can involve participants getting better at the task, becoming fatigued, or expecting certain outcomes based on previous conditions.

A specific type of order effect where the experience in one condition influences the performance or perception of later conditions. For example, a positive experience in one condition might make later conditions seem less positive.

A systematic way to control for order effects by creating different sequences of conditions and assigning participants to each sequence randomly. This ensures that each condition appears in each position of the sequence equally often.

A type of counterbalancing where every possible order of conditions is presented an equal number of times. This ensures each condition appears at each position in the sequence equally often.

A type of counterbalancing where the order of conditions is randomly determined for each participant. This is a simpler method compared to full counterbalancing.

A way to ensure that your study truly measures what it intends to measure. This involves considering whether the chosen variables accurately represent the psychological phenomena you are interested in studying.

A research design where the independent variable is not manipulated, but only measured. This means researchers cannot conclude causality, only correlations.

A research method that aims to repeat a previous study using the same procedures to see if the same results are obtained.

An ethical concern that occurs when positive results are more likely to be published than negative ones, leading to a biased view of the evidence. This is like only hearing about successful experiments, leaving out the failures.

A set of research practices that intentionally manipulate data to produce more favorable results. These practices harm the trustworthiness of research.

A research method that involves collecting data through systematic observation and experience, often using controlled experiments.

A movement that promotes transparency and accountability in science by openly sharing research materials and data.

The practice of outlining a research plan before collecting data, including the specific hypotheses, methods, and analyses. This promotes rigorous research and reduces bias.

The idea that scientific findings should be shared publicly, allowing for collaboration, peer review, and replication.