 Performance LFQA DPR-based retriever (vblagoje/dpr-question_encoder-single-lfqa-wiki and vblagoje/dpr-ctx_encoder-single-lfqa-wiki) slightly underperform 'state-of-the-art' Krishna et al. "Hurdles to Progress in Long-form Question Answering" REALM based retriever with KILT benchmark performance of 11.2 for R-precision and 19.5 for Recall@5.  