Lecture 7 Flashcards
What is the purpose of random assignment?
It attempts to balance participants by distributing them randomly (and evenly) across conditions
What does Random assignment help with?
It helps minimize the possibility of alternative explanation accounting for the results
What is Counterbalancing?
Alternating the order of condition assignment across subjects, reducing the possibility of potentially confusing order effects influencing the results
What is Validity?
How well an experiment procedure tests what it is designed to
What is Internal Validity?
The degree to which an experiment supports clear casual conclusions
What are some threats to Internal Validity?
- Confound
- Placebo effects
- Experimenter expectancy effects
What are confounding variables?
Two variables that are intertwined in such a way that we cannot determine which one has influenced a dependant variable
What is a Placebo?
Something that has no pharmacological effect
Why do Placebo effects reduce the internal validity of an experiment?
By introducing an alternative explanation for any differences observed across groups
What is the purpose of including a Placebo Group?
It provides an estimate of the placebo effect in the situation, which can be compared to the treatment group to determine whether there is any difference
What are Experimenter Expectancy effects?
When researchers can unintentionally influence the data they are collecting un subtle ways, based upon expectations related to their own predictions, hypotheses
What do Double-blind procedure help with?
Experimenter expectancy effects by keeping both the researcher and participant unaware of a condition assignment
What is External Validity?
The degree to which the results of a study can be generalized to other people, settings and conditions
What is the purpose of replication of experiments?
To increase confidence if the same results are obtained multiple times
What is cross-cultural eplications?
Testing whether effects generalize across cultures
