While this is much more rational in theory, it is more subject to estimation error, both honest and opportunitistic.

In practice, the channel state information is limited at the transmitter due to estimation errors and quantization.

However, the measurement of estimation error is not unproblematic, see Assessing and interpreting the accuracy of effort estimates.

A high estimation error cannot automatically be interpreted as an indicator of low estimation ability.

If the channel and noise distributions are known, then this a priori information can be exploited to decrease the estimation error.

The estimation error is given by:

However, this estimate was subject to considerable estimation error and may have also been influenced by attrition in the sample.

This iteration will continue until estimation error for total system power is smaller than some threshold, or it hits the specified number of iterations.

Robust optimization allows portfolio managers to introduce estimation error into the results.

These are deemed more robust to estimation errors.