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.
A membrane sweep is a way of trying to bring on labour to avoid going too overdue. It'll be the first step your midwife or doctor offers, before other methods of induction, to get your labour going.f you've passed your due date, you should be offered a membrane sweep before other methods of induction. You may be offered two or three membrane sweeps before your doctor or midwife suggests other ways for you to be induced. If you don't want to have a sweep, you can decline the offer.