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.
A flow variable in economics is a quantity that is measured over a time period. This is in contrast to stock variables, which are measured at a specific time. Flow variables can be measured over any time period but the most common include day, week, month, quarter and year.