ACM TOIS, the Big Sister of ACM TORS: Min Zhang’s Term as Editor-in-Chief Ends as the Impact Factor Rises to 11.2

When it comes to journals, Recommender-Systems.com usually focuses on ACM Transactions on Recommender Systems, or TORS. The reason is obvious: TORS is the ACM journal devoted to our field. Yet there is another journal in the “ACM Transactions on” family that recommender-systems researchers should follow closely. ACM Transactions on Information Systems, or TOIS, has published work on recommendation for decades and explicitly covers recommender systems as part of information retrieval and information access. The ACM Digital Library even lists “Recommender systems” as TOIS’s top subject for the previous year.

“Big sister” describes the relationship rather well. TOIS was established in 1983. TORS was announced in 2021, began accepting submissions in 2022, and published its first issue in 2023. TOIS therefore had almost four decades of history before TORS arrived. It is also much larger. ACM reports that TOIS now receives nearly 1,000 submissions per year, while its Digital Library profile includes 4,256 authors. Tsinghua University alone is associated with 98 TOIS papers. TORS is the younger, specialised journal; TOIS is the older venue in which recommender-systems research has long met information retrieval, search, user modelling, and evaluation.

This difference in age and size also deserves a small clarification. TORS has recommender systems in its title, but across the journals’ entire histories, TOIS has published more recommender-systems papers in absolute numbers. That is hardly surprising: TOIS has welcomed work on recommendation for decades, whereas TORS began publishing only in 2023. An annual comparison would be more difficult because ACM does not provide a convenient year-by-year topic count. TORS gives our field a dedicated home. TOIS handles a larger overall stream of papers and provides another important home in which recommendation meets information retrieval and information access.

One research community, two ACM journals

The close relationship between TOIS and TORS becomes clear when looking at their authors and editorial boards. Researchers such as Maarten de Rijke, Ruiming Tang, Maria Maistro, Xiangnan He, and Aixin Sun have published in both journals. Christine Bauer, Aixin Sun, Ruiming Tang, Shu Wu, and Lina Yao serve on both editorial boards. These overlaps are more than a coincidence. Recommender systems retrieve, rank, personalise, and evaluate information, while information-retrieval research increasingly studies user preferences, interaction, and recommendation. The two journals approach these questions from different starting points, but they draw on much of the same scientific community.

The organisational links are similarly close. TOIS is currently led by Editor-in-Chief Min Zhang of Tsinghua University, who is also a member of the ACM RecSys Steering Committee. The two TORS Editors-in-Chief, Li Chen and Dietmar Jannach, are members of the same committee. It also includes Christine Bauer, Tommaso Di Noia, and Rodrygo Santos, who serve on one or both of the journals’ editorial boards. TOIS and TORS have separate editorial processes, but they share many authors, reviewers, editors, and conference organisers. In practice, they are two journals within one closely connected research community.

ACM is looking for Min Zhang’s successor

Min Zhang has served as TOIS Editor-in-Chief since August 2020. Her term is now approaching its scheduled conclusion, and ACM has opened a call for nominations for the next Editor-in-Chief. The new appointment is expected to begin on 1 November 2026. Candidates may nominate themselves by submitting a CV and a statement outlining their plans for the journal. Other researchers may also nominate a candidate. Given the scale of the role, ACM explicitly welcomes joint applications from pairs or trios who would serve as co-Editors-in-Chief.

The search committee is chaired by Qiaozhu Mei and includes Maarten de Rijke, Yiqun Liu, Marc Najork, and Yi Zhang. Sartaj Sahni serves as liaison to the ACM Publications Board. The nomination deadline is 8 September 2026, although nominations may continue to be considered until the position has been filled. Nominations should be sent to Qiaozhu Mei. Prospective candidates may also consult ACM’s pages on the Editor-in-Chief appointment process, editorial responsibilities, and evaluation criteria.

Why could Min Zhang not simply continue for another term, even if she wished to do so? ACM journal Editors-in-Chief normally receive an initial three-year appointment followed by at most one renewal. Zhang has served since 2020 and is now completing the maximum two-term cycle. The search for a successor therefore follows ACM’s regular term-limit policy.

The next Editor-in-Chief will inherit considerable authority and responsibility. The EiC oversees the review process, appoints Associate Editors, shapes the editorial board, and has the final say on publication decisions. The position requires scientific vision and sound judgement, but also patience, fairness, organisation, and a willingness to deal with the many problems that readers never see. With almost 1,000 submissions each year, managing TOIS is less a side activity than a second academic life.

From 5.4 to 11.2

The timing of the search coincides with another piece of good news. TOIS’s Journal Impact Factor has increased from 9.1 to 11.2, a rise of more than 20 percent. The journal is now ranked seventh among 266 journals in Clarivate’s Computer Science, Information Systems category. This follows the previous increase from 5.4 to 9.1. Across two reporting cycles, TOIS has therefore moved from 5.4 to 11.2.

The impact factor is most useful as one journal-level signal among several. Citation patterns depend on research topics, publication volume, article types, and the wider development of a field. Still, an increase of this size deserves attention. It suggests that TOIS papers are reaching a growing audience at a time when information retrieval, recommender systems, and generative AI are moving closer together. Recent TOIS articles cover recommender agents, user-behaviour simulation, click-through-rate prediction, generative retrieval, and LLM-based evaluation. For recommender-systems researchers, TOIS has become even more relevant.

Beyond Clarivate’s Journal Impact Factor, TOIS also holds the highest category in the 2026 ranking of international publication venues maintained by the China Computer Federation. In the CCF area covering databases, data mining, and content retrieval, TOIS is ranked A, alongside journals such as ACM TODS and IEEE TKDE. TORS entered the same ranking for the first time at level C.

The distance between A and C reflects the difference in age and established reputation between the two journals, but the C rating should be read as good news for TORS. As we discussed when the ranking was announced, inclusion itself is a substantial achievement for a journal launched only a few years ago. Many journals in related areas are absent from the CCF list altogether, and TORS already shares its tier with ACM TIST. The ranking also has practical consequences because many Chinese institutions use CCF categories when assessing publications for recruitment, promotion, doctoral requirements, internal rewards, and grant reporting. TOIS’s A rating confirms its established position, while TORS’s early C rating marks an important step towards similar institutional recognition.

Credit to Min Zhang — and to the people behind the journal

Min Zhang is a professor in Tsinghua University’s Department of Computer Science and Technology. Her work covers information retrieval, recommender systems, user-behaviour analysis, machine learning, and data mining. Her Google Scholar profile records more than 20,000 citations and an h-index of 72. Tsinghua itself is ranked first in computer science by the U.S. News Best Global Universities subject ranking, while the 2026 QS and Times Higher Education rankings place it 11th and 12th respectively. Rankings use different methods, but they agree on Tsinghua’s position among the leading computer-science institutions.

The development of TOIS during Zhang’s term reflects the work of many people: its Senior Associate Editors, Associate Editors, reviewers, authors, and ACM staff. A journal of this size depends on all of them. Still, the Editor-in-Chief is the person responsible for keeping the whole system moving: finding editors for growing areas, handling conflicts, following delayed reviews, making difficult decisions, and maintaining consistency across hundreds of submissions.

Most of this work remains invisible. Readers see the published papers. They rarely see the difficult decisions, the delayed reviews, the conflicts, the reminders, and the constant coordination behind them. Steering a journal such as TOIS for six years requires judgement, patience, and a great deal of sustained academic service.

Min Zhang approaches the end of her term with TOIS receiving close to 1,000 submissions per year, an impact factor of 11.2, and a clear role at the intersection of information retrieval and recommender systems. That is a remarkable point at which to hand the journal to its next editorial leadership.

Congratulations to Min Zhang and everyone who contributed to this development. TOIS is in a strong position, and the next editorial team will inherit both a respected journal and a very full inbox. We wish Min all the best for her next projects—and hope that ACM finds successors with the vision, fairness, organisational skill, and healthy resistance to stress that the role will require.