External Validity Versus Ecological Validity
Ecological validity is often confused with external validity (which deals with the ability of a study's results to generalize). While these forms of validity are closely related, they are independent--a study may possess external validity but not ecological validity, and vice-versa . For example, mock-jury research is designed to study how people might act if they were jurors during a trial, but many mock-jury studies simply provide written transcripts or summaries of trials, and do so in classroom or office settings. Such experiments do not approximate the actual look, feel and procedure of a real courtroom trial, and therefore lack ecological validity. However, the more important concern is that of external validity--if the results from such mock-jury studies generalize to real trials, then the research is valid as a whole, despite its ecological shortcomings. Nonetheless, improving the ecological validity of an experiment typically improves the external validity as well.
In the original meaning of this term however it would be impossible to refer to a study's 'ecological validity' since this can only be a property of stimuli used in a perceptual experiment. Brunswick first introduced this term but the popular use (meaning basically 'realistic') has overtaken it, at least in A Level Psychology circles. For the original (and some feel correct) use see the entry on 'ecological validity - perception' and especially the paper by Hammond, 1998, which is referred to there. This can be accessed at: http://www.albany.edu/cpr/brunswik/notes/essay2.html Brunwick's term which is closer to the current 'pop' meaning of ecological validity is 'representative design'.
Read more about this topic: Ecological Validity
Famous quotes containing the words external, validity and/or ecological:
“Nature predominates over the human will in all works of even the fine arts, in all that respects their material and external circumstances. Nature paints the best part of the picture, carves the best of the statue, builds the best part of the house, and speaks the best part of the oration.”
—Ralph Waldo Emerson (1803–1882)
“It does not follow, because our difficulties are stupendous, because there are some souls timorous enough to doubt the validity and effectiveness of our ideals and our system, that we must turn to a state controlled or state directed social or economic system in order to cure our troubles.”
—Herbert Hoover (1874–1964)
“Could it not be that just at the moment masculinity has brought us to the brink of nuclear destruction or ecological suicide, women are beginning to rise in response to the Mother’s call to save her planet and create instead the next stage of evolution? Can our revolution mean anything else than the reversion of social and economic control to Her representatives among Womankind, and the resumption of Her worship on the face of the Earth? Do we dare demand less?”
—Jane Alpert (b. 1947)