What is the effect of neutral documents in the validation queue on Recall?

The effect of neutral documents in the validation queue on Recall is best understood by looking at the definition of Recall in the context of information retrieval, particularly in legal document review. Recall measures the system's ability to identify all relevant documents within a dataset.

When neutral documents—those that are neither relevant nor irrelevant—are included in the validation queue, they can interfere with the assessment of relevant documents. Since Recall is defined as the ratio of relevant documents retrieved to the total number of relevant documents available, the introduction of neutral documents to the evaluation process tends to dilute the effectiveness of the system in identifying true positives. As a result, the presence of these neutral documents can lead to a decrease in the overall Recall score because they may prevent actual relevant documents from being recognized or prioritized appropriately during the review process.

Consequently, the presence of neutral documents in the validation queue lowers Recall, as they do not contribute to the identification of relevant information and instead only add to the complexity and potential confusion surrounding which documents should truly be considered significant. This understanding highlights the importance of accurately categorizing documents as either relevant or irrelevant to maintain optimal Recall performance in a document review context.