Catch All Flashcards
What is random assignment in experimental research?
Random assignment is the process of assigning participants to different conditions in an experiment purely by chance, ensuring that each participant has an equal likelihood of being in any group.
Why is random assignment important in experiments?
It helps eliminate confounding variables and ensures that differences in results are due to the manipulation of the independent variable, thus increasing internal validity.
What two key criteria must an experiment have?
(1) Random assignment of participants to conditions and (2) Manipulation of an independent variable.
Why is manipulation necessary in an experiment?
It allows researchers to establish cause-and-effect relationships by systematically altering an independent variable and observing its impact on the dependent variable.
What is the difference between internal and external validity?
Internal validity refers to the extent to which the independent variable truly causes changes in the dependent variable, whereas external validity is the extent to which the findings can be generalized to real-world settings.
How does random assignment affect internal validity?
It enhances internal validity by ensuring that differences between groups are due to the manipulation of the independent variable and not other factors.
What is a key advantage of a between-subjects design?
It avoids carryover effects, as participants are only exposed to one condition.
What is a disadvantage of a within-subjects design?
It may suffer from order effects, where prior exposure to conditions influences later responses.
What is the recommended minimum number of respondents per condition?
At least 50 participants per condition, though more is preferable for statistical power.
How would you describe a 2 × 2 between-subjects design?
A design with two independent variables, each with two levels, where participants are assigned to only one of the four possible conditions.
What distinguishes a quasi-experiment from a true experiment?
A quasi-experiment lacks random assignment, making it harder to infer causality.
What is a cross-sectional study?
A study that observes different groups at one point in time rather than tracking changes over time.
What is a manipulation check?
A test to ensure that an experimental manipulation had its intended effect.
How do pretests differ from pilot studies?
Pretests assess experimental stimuli before the main study, while pilot studies test the entire experimental procedure on a small scale.
What is Cronbach’s alpha used for?
To measure the internal consistency (reliability) of a summated scale.
Why is reverse coding used in survey research?
To ensure that all items measuring the same construct are consistently coded before computing a summated scale.
Why are control conditions important in experiments?
They provide a baseline for comparison to determine the true effect of the manipulation.
What is counterbalancing in experimental design?
A technique used in within-subjects designs to control for order effects by varying the sequence of conditions.
How can demand effects be reduced in a study?
By using vague study descriptions, adding filler tasks, and including hypothesis-guessing questions.
What is a double-barreled survey question?
A question that asks about two different things simultaneously, making it unclear which aspect the respondent is addressing.
