Jamie Callan

Timeline

1. 1993

   A PhD at UMass Amherst

   He receives his PhD from the Department of Computer Science at the University of Massachusetts Amherst in 1993. He also holds a BA in Applications of Computer Science from the University of Connecticut and an MS in Computer and Information Science from UMass, and he works for seven years as a software engineer at Digital Equipment Corp.

2. 1993–1999

   Assistant Director of the CIIR

   After his PhD, he joins UMass's Center for Intelligent Information Retrieval as a Senior Post-doctoral Research Associate and later becomes a Research Assistant Professor. From 1995 to 1999, he is the Center's Assistant Director.

3. 1999–2007

   SIGIR treasurer, then chair

   In 1999, he leaves UMass for a tenure-track professorship at Carnegie Mellon University. He serves as treasurer of ACM SIGIR from 1999 to 2003 and as its chair from 2003 to 2007.

4. 2019

   BERT and DeepCT for retrieval

   In 2019, he and Zhuyun Dai study BERT for text understanding in information retrieval and find its contextual representations more effective than traditional word embeddings. Their DeepCT framework maps BERT's contextualized representations to term weights that an ordinary inverted index can store for passage retrieval.

5. February 2020–August 2021

   Interim director of LTI

   LTI founder Jaime Carbonell dies in February 2020, and he is appointed interim director of the Language Technologies Institute. He steps down in August 2021 to devote more time to teaching and research.

6. 2021

   ACM SIGIR Academy induction

   In 2021, he is one of five researchers inducted into the ACM SIGIR Academy, which honors significant, cumulative contributions to the development of information retrieval.

7. 2022

   ClueWeb22 and HyDE

   In 2022, he coauthors ClueWeb22 with Arnold Overwijk, Chenyan Xiong, Xiao Liu and Cameron VandenBerg, a dataset of 10 billion web pages built by the Lemur Project with support from Microsoft. He also coauthors HyDE with Luyu Gao, Xueguang Ma and Jimmy Lin, which has an instruction-following language model write a hypothetical document for each query and retrieves real documents by embedding it.

8. As of October 2026

   LTI professor and PhD director

   He is a professor at Carnegie Mellon's Language Technologies Institute and the Institute's Ph.D. Program Director. His research applies neural techniques and large language models to retrieval, including term weighting, conversational retrieval and retrieval-augmented generation, and he maintains and distributes the ClueWeb datasets.