Sleep related groaning, also called catathrenia, causes you to groan vocally while you sleep. Sleep related groaning is a long-lasting disorder that often occurs nightly. The groaning sound is usually quite loud. Your breathing becomes unusually slow during a groaning episode. You take in a slow, deep breath.
The Gini coefficient (or Gini ratio) is a summary statistic of the Lorenz curve and a measure of inequality in a population.he Gini coefficient (or Gini ratio) is a summary statistic of the Lorenz curve and a measure of inequality in a population.
In mathematics,  a coefficient is a multiplicative factor in some term of a polynomial, a series or any expression; it is usually a number, but may be any expression. In the latter case, the variables appearing in the coefficients are often called parameters, and must be clearly distinguished from the other variables.