Lesson no 9:Research Methods in Psychology (II):Short Question
What is the main goal of experimental research? The main goal of experimental research is to determine cause-and-effect relationships by manipulating an independent variable and observing its effect on a dependent variable.
In an experiment, what is the Dependent Variable (DV)? The Dependent Variable is the measure of behavior that is expected to change as a result of manipulating the Independent Variable.
What is the key feature that distinguishes a quasi-experiment from a true experiment? In a quasi-experiment, the researcher does not randomly assign participants to groups; the independent variable occurs naturally or has already occurred.
What does “ex post facto” mean? “Ex post facto” means “after the fact.”
In a prospective quasi-experimental design, when are variations in the independent variable measured? They are measured as they occur, rather than retrospectively.
What is the primary purpose of a single-case research design? The primary purpose is to focus intensively on a single subject or case, often used for rare conditions or detailed analysis of an individual.
What is meta-analysis? Meta-analysis is a statistics-based method that combines the results of several independent studies on the same topic to draw an overall conclusion.
In a classical experiment design, what is the standard format for groups? It typically involves an experimental group (receives treatment) and a control group (does not receive treatment), with measurements taken before and after for both.
Why is random assignment to groups important in a true experiment? Random assignment helps ensure that the groups are equivalent at the start of the experiment, minimizing the influence of pre-existing differences between participants (confounding variables) on the results.
How does a quasi-experiment attempt to establish comparability between groups if random assignment is not used? It uses “matching,” where subjects in the exposure and comparison groups are matched on key characteristics (e.g., age, gender) to make them as similar as possible.
Explain one ethical issue associated with experimental research. One ethical issue is deception; sometimes researchers cannot fully inform participants about the nature of the experiment without compromising the results, which raises ethical concerns about informed consent.
What is the advantage of using a time-series design in quasi-experimentation? It allows researchers to observe whether changes in the dependent variable occur in apparent response to changes in an independent variable over time, strengthening the inference of a causal relationship.
Why might a researcher choose a single-case design over a group design? A single-case design is chosen when studying a rare phenomenon, when a group is not available, or for conducting an in-depth analysis of the effect of a treatment on a specific individual.
How does a retrospective design differ from a prospective design? A retrospective design looks back at data where the independent variable has already occurred, while a prospective design follows subjects forward in time, measuring the independent variable as it occurs.
What is the primary limitation of quasi-experimental designs? The primary limitation is the lack of random assignment, which makes it difficult to definitively establish cause-and-effect relationships because other, unmeasured variables could explain the results.
How does meta-analysis contribute to the body of psychological knowledge? It provides a more powerful and precise estimate of the true effect of a variable or treatment by statistically combining data from multiple studies, offering stronger conclusions than any single study.
What is the purpose of a control variable in an experiment? A control variable is a potential independent variable that is held constant to prevent it from influencing the dependent variable and confounding the results.
A researcher studies the academic achievement of identical twins who were raised apart. What type of research design is this? This is a Quasi-Experiment, specifically an adoption study using twins.
In an experiment on test anxiety, one group receives relaxation therapy and the other does not. The group that does not receive therapy is the __________. Control Group.
A researcher analyzes the combined results of 20 different studies on the effectiveness of a specific psychotherapy for depression. What technique are they using? They are using Meta-Analysis.
A school implements a new anti-bullying program and then tracks disciplinary reports over the next three years to see if they decrease. What quasi-experimental design is this? This is a Time-Series Design.
A study compares the career choices of children from high-income families versus low-income families, without manipulating their income. What type of design is this? This is a Quasi-Experiment (specifically an ex post facto design).
Identify a potential confounding variable in a study linking coffee consumption to heart disease, if the study is not an experiment. A potential confounding variable could be stress levels; stressed people might drink more coffee and also be at higher risk for heart disease.
A clinical psychologist develops a new treatment for a specific phobia and carefully applies it to one client, measuring the client’s fear before, during, and after treatment. What design is this? This is a Single-Case Research Design.
A researcher wants to study the long-term effects of childhood nutrition on adult health by examining medical records of people now in their 50s. What type of quasi-experimental design is this? This is a Retrospective or Ex Post Facto Design.
