???? ??????????? ?????? ??????? ???????? ??? ?? ????????, ?????????? ????????? ???????? ??????? ????? «???? ?????????» ?? ??????? ?????.????????? ???????????? ?????? ????? ????? ??????? ???? «??????? ??????»There might be two types of variances in stats, namely, sample variance and population variance. The symbol of variance is specified by ?2.