Vijay Koshti Statistics ( Statistical concepts and related articles)

  Regression  ©   The term ‘regression’, literally means ‘stepping back towards the average’. It was first used by a British Biometrician Sir Francis Galton (1822-1911). He found that although tall parents have tall children, the average height of children is less than the average height of their parents and although short parents have short children, average height of children is more than the average height of their parents. In other words the average height of children of tall parents or short parents will regress or go back to the average height of population.  ( This is like: संत ज्ञानेश्वरांच्या ओवीप्रमाणे ' न्यून ते पुरते , अधिक ते सरते ') This phenomenon was described by him as 'regression’.   Definition:  The method of estimating the value of one variable when that of the other is           known and the variables are known to be correlated. Lines of regression:-        We know that...

  Elements of demography © Life is a three pages book, two are already written by God. The first is birth, last is death, the middle page is empty. Fill it with smile, love, faith and honey. introduction:   Demography means population studies. In demography, we study the events related to human life. Events related to human life such as birth, death, sickness, marriage, divorce, migration etc. are called vital events . Vital statistics is a study of vital events. Vital statistics give numerical summary regarding vital events. It is necessary to study the methods of population projection to estimate average life expectancy, sex ratio, dependency ratio, population density, infant mortality rate and percentage of literacy etc. In this chapter, we study statistical methods of measuring birth rates, death rates, population growth rates. 3.1 Methods of Obtaining Vital Statistics The raw data of the vital statistics are generally obtained from the following sou...