The varying performance of information retrieval (IR) methods, including state-of-the-art transformer-based neural retrievers, across diverse queries poses a significant challenge for achieving robust and reliable retrieval effectiveness. Query Performance Prediction (QPP) seeks to estimate the effectiveness of a retrieval method for individual queries, enabling adaptive strategies to improve retrieval outcomes, particularly for challenging queries. However, existing QPP approaches face fundamental challenges: pre-retrieval methods often rely on surface-level query features that fail to capture the nuanced relationship between queries and retrieval effectiveness, while post-retrieval methods depend heavily on the quality of retrieved documents, which can be unreliable for difficult queries. To this end, we propose the Query Space Distance-Based QPP ( QSD-QPP ) framework, which leverages the deterministic and consistent behavior of retrieval methods to estimate query performance by referencing historical queries with known effectiveness. The approach is motivated by the observation that semantically or syntactically similar queries often exhibit consistent retrieval performance, a property that can be exploited to make reliable predictions for unseen queries. QSD-QPP operates in two modes: (1) a lightweight pre-retrieval instantiation that dynamically constructs a query subspace based on embedding distances to interpolate the performance of proximate historical queries, and (2) an enriched post-retrieval instantiation that incorporates contextualized embeddings, document interactions, and historical query associations to enhance prediction accuracy. By utilizing large-scale contextualized embeddings derived from pre-trained language models, QSD-QPP efficiently identifies semantically similar queries and leverages their performance for robust predictions. By addressing the inherent limitations of prior approaches, QSD-QPP achieves a balanced trade-off between computational efficiency, prediction accuracy, and scalability. We evaluate QSD-QPP on four benchmark datasets, including MS MARCO Dev and TREC Deep Learning tracks (2019, 2020, and DL-Hard), demonstrating its superior accuracy and robustness compared to state-of-the-art baselines in both pre-retrieval and post-retrieval QPP tasks. To ensure reproducibility and encourage further research, we publicly release the implementation of our work.

Estimating query difficulty, also known as Query Performance Prediction (QPP), is concerned with assessing the retrieval quality of a ranking method for an input query. Most traditional unsupervised frequency-based models and many recent supervised neural methods have been designed specifically for predicting the performance of sparse retrievers such as BM25. In this paper we propose an unsupervised QPP method for dense neural retrievers which operates by redefining the well-known concept of query robustness i.e., a more robust query to perturbations is an easier query to handle. We propose to generate query perturbations for measuring query robustness by systematically injecting noise into the contextualized neural representation of each query. We then compare the retrieved list for the original query with that of the perturbed query as a way to measure query robustness. Our experiments on four different query sets including MS MARCO, TREC Deep Learning track 2019 and 2020 and TREC DL-Hard show consistently improved performance on linear and ranking correlation metrics over the state of the art.

Query Performance Prediction (QPP) is focused on estimating the difficulty of satisfying a user query for a certain retrieval method. While most state of the art QPP methods are based on term frequency and corpus statistics, more recent work in this area have started to explore the utility of pretrained neural embeddings, neural architectures and contextual embeddings. Such approaches extract features from pretrained or contextual embeddings for the sake of training a supervised performance predictor. In this paper, we adopt contextual embeddings to perform performance prediction, but distinguish ourselves from the state of the art by proposing to directly fine-tune a contextual embedding, i.e., BERT, specifically for the task of query performance prediction. As such, our work allows the fine-tuned contextual representations to estimate the performance of a query based on the association between the representation of the query and the retrieved documents. We compare the performance of our approach with the state-of-the-art based on the MS MARCO passage retrieval corpus and its three associated query sets: (1) MS MARCO development set, (2) TREC DL 2019, and (3) TREC DL 2020. We show that our approach not only shows significant improved prediction performance compared to all the state-of-the-art methods, but also, unlike past neural predictors, it shows significantly lower latency, making it possible to use in practice.

Researchers have shown that it is possible to identify reported instances of personal life events from users' social content, e.g., tweets. This is known as personal life event detection. In this paper, we take a step forward and explore the possibility of predicting users' next personal life event based solely on the their historically reported personal life events, a task which we refer to as personal life event prediction. We present a framework for modeling streaming social content for the purpose of personal life event prediction and describe how various instantiations of the framework can be developed to build a life event prediction model. In our extensive experiments, we find that (i) historical personal life events of a user have strong predictive power for determining the user's future life event; (ii) the consideration of sequence in historically reported personal life events shows inferior performance compared to models that do not consider sequence, and (iii) the number of historical life events and the length of the past time intervals that are taken into account for making life event predictions can impact prediction performance whereby more recent life events show more relevance for the prediction of future life events.