1 Polyps: Benign growths in the uterine lining (endometrium) can cause a heavy or prolonged period. 2  Ovary dysfunction: Lack of ovulation (anovulation) results in a lack of progesterone, causing heavy periods. 3  Adenomyosis: When glands from the uterine lining embed in uterine muscle, heavy bleeding can occur.
Mean and Variance of Random Variables. The mean of a random variable provides the long-run average of the variable, or the expected average outcome over many observations.
More about Variable. In the mathematical context, a variable is a quantity which has a changing or a variable magnitude. Commonly (in algebra), it is represented by an English letter or a Greek letter. It is common practice to call this symbolic letter the variable.