Exam 2 Flashcards
(92 cards)
A research design which you test a claim about a variable by exposing people to the variable of interest. You then note that these people feel,think or behave as expected.
Pseudo Experiments
Some people are just good at playing SAT, bowling etc. This deficiency in randomization makes it harder to rule out confounding variables and introduces new threats to internal validity
Problem with Pseudo Experiments
why is internal validity high in experiments?
Internal Validity is high in experiments because the only thing you are maniputaing is the IV and everything else is held constant.
A ___ has a large N, Control group, and random assignment of participants to different experimental conditions.
true experiment
The extent to which the IV caused the change observed in your DV, extent to which your findings provide information about causality.
Internal Validity
Selection bias History & Maturation Regression to the mean Repeated Testing Attrition Reaction Bias Experimenter Bias Examples of
Threats to internal Validity
the bias introduced by the selection of individuals, groups or data for analysis in such a way that proper randomization is not achieved, thereby ensuring that the sample obtained is not representative of the population intended to be analyzed. Sampling people from an unrepresentative samples
Selection Bias
Type of selection bias
Non-response bias
A type of selection bias which results from the fact that people who choose to answer surveys are systematically different from people who choose not to answer surveys. example (election of 1936 FDR vs Landon) Literary digest study
Non-response bias
Changes that are occurring across the board in a very large group of people, changes could be due to historical event or IV. example study of PTSD during 9/11
History
Specific developmental changes that are occuring in a particular person or group or age cohort. Exmpl. Kids on pills start treatment at 2 at 3 child is maturin not sure if treatment or child is affecting results.
Maturation
difference between maturation & history
Maturation is at an individual level, history is population level.
Tendency for people who receive high or low scores on a particular measure to score closer to the mean on later testing. example sophmore slump in sports. if you score at an extreme the first time the second time you are more likely to score closer to the mean.
Regression to the mean
two types of score
true score, observed score
a persons actual ability
true score
persons measured ability (true score +error)
observed score
If you have lots of errors the 1st test, bound to be lest errors at the 2nd. at that point there is only one way for the score to go towards the mean. This is a better indicator of a persons
true score, actual ability
Tendency for participants to perform better on a test or personality measure the second time they take it
Repeated Testing
why people do better the second time they take a test?
Learning (IQ test)
practice
figuring out what kinds of responses are sociably desirable (personality test)
Solution for repeated testing
pre and post assessment test
eliminate the pretest
Test for all participants with 1/2 randomly assigned to receive the treatment and 1/2 randomly assigned to not receive the treatment
pre and post assessment
problem with pre and post assessment?
you’re not getting ride of repeated testing
randomly assign 1/2 people to get treatment and 1/2 not to get treatment. the random assignment will make it likely that the 2 groups were equivalent at pretest. (this relies on random assignment)
eliminate the pretest
dropping out, problem for longitudinal studies.
attrition
