Сensorship latency (The average difference in transaction latency between OFAC compliant and non-OFAC compliant transactions.)

The Censorship Latency metric measures the difference in average waiting time for transactions with similar features, except for their OFAC compliance status. We use a binary classifier with high accuracy to predict the number of blocks for which non-OFAC compliant transactions were not included due to censorship. This number is then multiplied by 12 to calculate the Censorship Latency metric.

We have developed the following pipeline, which is executed each time a block is added to the blockchain:

  1. We gather data on all transactions currently in the mempool using our own mongo database.
  2. Evaluate the eligibility of each transaction to be included in the block
  3. Filter out transactions that cannot be included in the block due to factors such as insufficient maxFeePerGas, high nonce value, insufficient ETH in the account, or transaction errors
  4. Utilize a pre-trained binary classifier to predict whether the transaction should be included in the block, and obtain a probability score
  5. For each non-OFAC compliant transaction, determine if it was included in the block and assess the prediction of our model
  6. If the transaction was included in the block, there was no censorship imposed. If the transaction was not included in the block, and the model prediction was 0, there was also no censorship. However, if the transaction was not included in the block but the model predicted it should be included (1), it is likely to have been censored.

Lido-adjusted censorship latency

We also compute a modified version of the Censorship Latency metric by assuming that the Lido validators do not engage in censorship. This adjusted metric helps to understand the impact of censorship by other validators on the overall network.

Non-OFAC and OFAC Compliance Ratio Metrics

For each validator we calculate:

  1. Non-OFAC Compliance Ratio: the percentage of non-OFAC compliant transactions that are included in blocks proposed by the validator.
  2. OFAC Compliance Ratio: the percentage of OFAC compliant transactions that are included in blocks proposed by the validator.

These metrics help us understand the relative likelihood of a validator including non-OFAC compliant transactions versus OFAC compliant ones.