Chapter 8: Quasi-Experimental Design

A collection of flashcards covering vocabulary and key concepts related to quasi-experimental design in research.

Quasi-experimental

Research that resembles experimental research but is not true experimental research.

Internal validity

The degree to which a study accurately establishes a causal relationship between treatment and outcome.

Random assignment

The process of assigning participants to different conditions in an experiment randomly.

Counterbalancing

A method used to control for the effects of order in within-subject design experiments.

One-Group Posttest Only Design

A quasi-experimental design where a single group receives a treatment and is measured after.

One-Group Pretest-Posttest Design

A quasi-experimental design that measures a group before and after a treatment.

Regression to the mean

The statistical phenomenon where extreme scores tend to be closer to the average on subsequent measures.

Spontaneous remission

The natural improvement of a condition without treatment over time.

Interrupted time series design

A quasi-experimental design where a treatment interrupts a time series of measurements.

Nonequivalent groups design

A design in which participants have not been randomly assigned to groups, leading to potential biases.

Pretest-Posttest Nonequivalent Groups Design

A design that compares pretest and posttest scores of a treated group and a control group.

Control group

A group that does not receive treatment and is used for comparison in an experiment.

Field settings

Real-world environments where research can be conducted, often lacking control over variables.

Confounding variables

Variables other than the independent variable that may affect the dependent variable.

Treatment effectiveness

A measure of how well a treatment achieves its intended outcome.

Testing effect

Changes in participant behavior or responses as a result of being measured multiple times.

Instrumentation effect

Changes in the measurement tools or procedures that may affect data collection over time.

History effect

Influences on the dependent variable due to external events occurring between measurements.

Maturation effect

Changes that occur naturally in participants over time, affecting the outcome.

The Fatal Flaw

The lack of a control group in a one-group design that prevents proper attribution of results.

Treatment switch

The phase in switching replication designs when the treatment moves from one group to another.

Phase 1 in Switching Replication

Initial measurement of the dependent variable in both groups before any treatment.

Phase 3 in Switching Replication

First posttest measurement after the treatment has been administered to the treatment group.

Phase 5 in Switching Replication

Final posttest measurement after treatment has switched groups.

Demand characteristics

Cues in an experiment that might inform participants about expected behaviors or outcomes.

Placebo effects

Improvements in a participant's condition that result from their expectations rather than the treatment.

Experimenter expectancy effects

Variations in participants' responses based on cues inadvertently provided by the researcher.

Staggered treatment effects

Treatment effects that are induced in a staggered manner across different groups.

Reversal effect

The phenomenon where the cessation of treatment leads to a reversal of its effects.

Causal evidence

Evidence that clearly shows a cause-and-effect relationship.

Educational interventions

Programs or strategies implemented to improve educational outcomes for students.

Therapeutic interventions

Approaches designed to improve emotional, psychological, or physical well-being through treatment.

Comparative effectiveness

An assessment of the relative benefits of two or more treatments.