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.
Planning the Methodology - Qualitative Variables. A variable is any entity that can take on different values. OK, so what does that mean? Anything that can vary can be considered a variable. For instance, age can be considered a variable because age can take different values for different people or for the same person at different times. Similarly, country can be considered a variable because a person's country can be assigned a value.