Test 3 Flashcards
Validity
Validity: the extent to which empirical evidence and theoretical rationales support the adequacy and appropriateness of conclusions drawn from some form of assessment.
Construct validity:
Construct validity: the ability of a measurement tool or test to accurately measure what it’s supposed to measure.
Internal validity:
Internal validity: the extent to which a piece of evidence supports a claim about cause and effect.
External validity:
External validity: the extent to which the findings of a study are relevant to subjects and settings beyond those in the study
Increasing internal validity often means
sacrificing external validity
And vice versa
External validity asks the question of generalizability:
To what: situations, people, settings, and variables can an effect be generalized?
Ask a research question about a population. ->
Take a representative sample from the population. ->
Answer the research question by studying the sample. ->
Generalize results from the study of the sample to population.
“What is true of the sample is true of the population”
Ask a research question about a population. ->
Take a representative sample from the population. ->
Answer the research question by studying the sample. ->
Generalize results from the study of the sample to population.
“What is true of the sample is true of the population”
The Artificiality Criticism
Scientific experiments are useless because they are artificial and not like “real life”
This assumes that “Real Life” is a better setting for experiments than a controlled laboratory setting.
Why is that a poor assumption to make?
Scenario Number one:
Experiment generalizes to real world.
If scenario one is the goal, then EV is required.
Scenario number two:
Real world inspires Experiment.
If Scenario two is the goal, the EV is not required.
Harlows Monkeys
In the 50s it was believed that a baby’s attachment to their mother was because they fed the baby.
Hunger reduction model of maternal love.
Are the infant monkeys representative of all infant monkeys?
Does the experimental setting approximate real life?
Is the subject’s behavior is influenced by the experimental setting?
Then FAIL: little external validity.
Harlows Monkeys
In the 50s it was believed that a baby’s attachment to their mother was because they fed the baby.
Hunger reduction model of maternal love.
Are the infant monkeys representative of all infant monkeys?
Does the experimental setting approximate real life?
Is the subject’s behavior is influenced by the experimental setting?
Then FAIL: little external validity.
Why conduct controlled experiments if the results don’t/can’t apply to the real world?
Because:
There are inherent benefits to doing these things in and of themselves.
- Ask whether something can happen rather than does happen
- prediction may specify that something should happen in the lab, so test it out.
- Demonstrate the power of the phenomenon by showing that it occurs in a contrived setting.
- Use the Lab to produce conditions that otherwise do not exist in the real world.
Experimental findings not intended to be generalized can still be worthwhile in theory development!
Harlow’s experiment failed to meet the requirements of external validity.
Harlow had no intention of generalizing these results.
He showed that the hunger reduction model didn’t hold up as it should.
Theoretical proposition:
Theoretical proposition: Parent approval/disapproval shape childrens grammatically correct speech.
Prediction: The observed parents ought to do this (disconfirmed by study).
Subjects are of interest precisely because they are unrepresentative.
Past theories and evidence → current theory and evidence → predictions
Past theories and evidence → current theory and evidence → predictions
“BREAKTHROUGH” HEADLINES
• Media headlines often present research findings as “major breakthroughs” . May spread misinformation and exaggeration