It can be estimated using a number of different strategies.
The years of Jesus' ministry have been estimated using three different approaches.
This model does however still have a number of unknown free parameters which can be estimated using system identification.
Within this level, fair value is also estimated using a valuation technique.
Beta can be estimated for individual companies using regression analysis against a stock market index.
As a result, much of the data for the index must come from other sources, or is estimated using regressions.
The distance to Messier 87 has been estimated using several independent techniques.
Other times, it may be possible to estimate using an explicit method and maintain stability.
The parameter k is to be estimated using experimental data.
The parameter can be estimated using a fixed point algorithm.