Estimation

In many real-life problems, the population parameter(s) is (are) unknown and someone is interested to obtain the value(s) of parameter(s). But, if the whole population is too large to study or the units of the population are destructive in nature or there is limited resources and manpower available then it is not practically convenient to examine each and every unit of the population to find the value(s) of parameter(s). In such situations, one can draw sample from the population under study and utilize sample observations to estimate the parameter(s).