An observed effect that is of a size that would rarely occur by chance is called
A) a randomized effect.
B) the confounding effect.
C) a statistically significant effect.
D) the placebo effect.

Question

Quizplus · Accepted Answer

When an observed effect is of a size that is unlikely to occur by chance, we call it a statistically significant effect. It means that the probability of obtaining the result by chance is very low. The other options do not fit the description given. The placebo effect refers to a response to a treatment that has no therapeutic effect. The confounding effect is when an extraneous variable affects the outcome of a study. The randomized effect is not a commonly used term in statistics.

An Observed Effect That Is of a Size That Would