Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Query Embedding Pruning for Dense Retrieval   Recent advances in dense retrieval techniques have offered the promise of
being able not just to re-rank documents using contextualised language models
such as BERT, but also to use such models to identify documents from the
collection in the first place. However, when using dense retrieval approaches
that use multiple embedded representations for each query, a large number of
documents can be retrieved for each query, hindering the efficiency of the
method. Hence, this work is the first to consider efficiency improvements in
the context of a dense retrieval approach (namely ColBERT), by pruning query
term embeddings that are estimated not to be useful for retrieving relevant
documents. Our proposed query embeddings pruning reduces the cost of the dense
retrieval operation, as well as reducing the number of documents that are
retrieved and hence require to be fully scored. Experiments conducted on the
MSMARCO passage ranking corpus demonstrate that, when reducing the number of
query embeddings used from 32 to 3 based on the collection frequency of the
corresponding tokens, query embedding pruning results in no statistically
significant differences in effectiveness, while reducing the number of
documents retrieved by 70%. In terms of mean response time for the end-to-end
to end system, this results in a 2.65x speedup.

36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
3
The categories of this paper are: physics
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
27
The categories of this paper are: comp-gas
24
The categories of this paper are: dg-ga
25
The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
4
The categories of this paper are: cond-mat
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
2
The categories of this paper are: math
7
The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys