The standard deviation of a random variable, statistical population, data set, or probability distribution is the square root of its variance. It is algebraically simpler, though in practice less robust, than the average absolute deviation.he variance is the mean of these values: and the population standard deviation is equal to the square root of the variance: This formula is valid only if the eight values with which we began form the complete population.
Report Abuse. 1  Sounds like the sweep worked. You will typically go into labor within 24-48 hours if a membrane sweep worked. 2  For some it doesn't work at all - if its going to work usually within 24hrs you are in labor. Invisible Pink RN Â· 7 years ago.
The modern view of membrane structure, known as the fluid mosaic model, was developed in 1972 by S. J. Singer and G. L. Nicholson and reflects three basic features of membrane structure. Integral membrane proteins, when viewed from above one surface or the other, contribute a mosaic or pebbled pattern to a membrane, and these proteins and the membrane lipids are capable of lateral movement in the plane of the membrane, due to the fluid nature of lipid association.