Fee and cost estimators can be configured via the config section [fee_estimation]:
Fee and cost estimators observe transactions on the network and use the observed costs of those transactions to build estimates for viable fee rates and expected execution costs for transactions. Estimators and metrics can be selected using the configuration fields above, though the default values are the only options currently. log_error controls whether or not the INFO logger will display information about the cost estimator accuracy as new costs are observed. Setting enabled = false turns off the cost estimators. Cost estimators are not consensus-critical components, but rather can be used by miners to rank transactions in the mempool or client to determine appropriate fee rates for transactions before broadcasting them.
The fuzzed_weighted_median_fee_rate uses a median estimate from a window of the fees paid in the last fee_rate_window_size blocks. Estimates are then randomly "fuzzed" using uniform random fuzz of size up to fee_rate_fuzzer_fraction of the base estimate.