The term is best known as a mechanical effect, and is used as an analogy to a falling row of dominoes. It typically refers to a linked sequence of events where the time between successive events is relatively small.
9 terms. What is the difference between a z test and a t-test. Z: tests probability sample was drawn from a population with a known mean and known standard deviation. T; tests probability sample was drawn from a population with known mean but unknown standard deviation. z-test.
The t-test is used to determine if there is a reliable difference between the mean of the before-treatment and the mean of the after treatment measurements. Sometimes, in very sophisticated (i.e., expensive) experiments, two groups of subjects are individually matched on one or more demographic characteristics. One group is exposed to a treatment (experimental group) and the other is not (control group).