A number of nonparametric methods exist when studying the population and its parameters in the situation when the distribution is unknown. Some of them such as "resampling bootstrap method" are based on resampling from an initial sample.

In this article empirical likelihood approach is introduced as a nonparametric method for more efficient use of auxiliary information to construct confidence regions.

In empirical likelihood approach a Lagrange multipliers method is applied to estimate ...(to countinue here)