The term ceiling effect has two distinct meanings, referring to the level at which an independent variable no longer has an effect on a dependent variable, or to the level above which variance in an independent variable is no longer measured or estimated. An example of the first meaning, a ceiling effect in treatment, is pain relief by some kinds of analgesic drugs, which have no further effect on pain above a particular dosage level. An example of the second meaning, a ceiling effect in data-gathering, is a survey that groups all respondents into income categories, not distinguishing incomes of respondents above the highest level asked about in the survey instrument.
Read more about Ceiling Effect: Treatment, Data-gathering
Famous quotes containing the words ceiling and/or effect:
“What made the ceiling waterproof?
Landor’s tarpaulin on the roof.”
—William Butler Yeats (1865–1939)
“We all have—to put it as nicely as I can—our lower centres and our higher centres. Our lower centres act: they act with terrible power that sometimes destroys us; but they don’t talk.... Since the war the lower centres have become vocal. And the effect is that of an earthquake. For they speak truths that have never been spoken before—truths that the makers of our domestic institutions have tried to ignore.”
—George Bernard Shaw (1856–1950)