{"title":"Session details: Session 2B - Conversational Search","authors":"Hamed Zamani","doi":"10.1145/3484641","DOIUrl":"https://doi.org/10.1145/3484641","url":null,"abstract":"","PeriodicalId":289271,"journal":{"name":"Proceedings of the 2021 ACM SIGIR International Conference on Theory of Information Retrieval","volume":"180 5-6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120917876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Session details: Session 1C - Content Analysis","authors":"Makoto P. Kato","doi":"10.1145/3484639","DOIUrl":"https://doi.org/10.1145/3484639","url":null,"abstract":"","PeriodicalId":289271,"journal":{"name":"Proceedings of the 2021 ACM SIGIR International Conference on Theory of Information Retrieval","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124492605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fairness and Control of Exposure in Two-sided Markets","authors":"T. Joachims","doi":"10.1145/3471158.3472226","DOIUrl":"https://doi.org/10.1145/3471158.3472226","url":null,"abstract":"A large number of two-sided markets are now mediated by search and recommender systems, ranging from online retail and streaming entertainment to employment and romantic-partner matching. I will discuss in this talk how the design decisions that go into these search and recommender systems carry substantial power in shaping markets and allocating opportunity to the participants. This does not only raise legal and fairness questions, but also questions about how these systems shape incentives and the long-term effectiveness of the market. At the core of these questions lies the problem of where to rank each item, and how this affects both sides of the market. While it is well understood how to maximize the utility to the users, this talk focuses on how rankings affect the items that are being ranked. From the items perspective, the ranking system is an arbiter of exposure and thus economic opportunity. I will discuss how machine learning algorithms that follow the conventional Probability Ranking Principle [1] can lead to undesirable and unfair exposure allocation for both exogenous and endogenous reasons. Exogenous reasons often manifest themselves as biases in the training data, which then get reflected in the learned ranking policy. But even when trained with unbiased data, reasons endogenous to the system can lead to unfair or undesirable allocation of opportunity. To overcome these challenges, I will present new machine learning algorithms [2,3,4] that directly address both endogenous and exogenous factors, allowing the designer to tailor the ranking policy to be appropriate for the specific two-sided market.","PeriodicalId":289271,"journal":{"name":"Proceedings of the 2021 ACM SIGIR International Conference on Theory of Information Retrieval","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121633558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effective and Privacy-preserving Federated Online Learning to Rank","authors":"Shuyi Wang, Bing Liu, Shengyao Zhuang, G. Zuccon","doi":"10.1145/3471158.3472236","DOIUrl":"https://doi.org/10.1145/3471158.3472236","url":null,"abstract":"Online Learning to Rank (OLTR) has been primarily studied in the centralised setting, where a central server is responsible to index the searchable data, collect the users' queries and search interactions, and optimize ranking models. A drawback of such a centralised OLTR paradigm is that it cannot guarantee user's privacy as all data (both the searchable one and the one related to user interactions) is collected by the server. In this paper, we propose a Federated OLTR method, called FPDGD, which leverages the state-of-the-art Pairwise Differentiable Gradient Descent (PDGD) and adapts it to the Federated Averaging framework. For a strong privacy guarantee, we further introduce a noise-adding clipping technique based on the theory of differential privacy to be used in combination with FPDGD. Empirical evaluation shows FPDGD significantly outperforms the only other federated OLTR method. In addition, FPDGD is more robust across different privacy guarantee requirements than the current method: our method is therefore more reliable for real-life applications.","PeriodicalId":289271,"journal":{"name":"Proceedings of the 2021 ACM SIGIR International Conference on Theory of Information Retrieval","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130114977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Semantic Hilbert Space for Interactive Image Retrieval","authors":"Amit Kumar Jaiswal, Haiming Liu, Ingo Frommholz","doi":"10.1145/3471158.3472253","DOIUrl":"https://doi.org/10.1145/3471158.3472253","url":null,"abstract":"The paper introduces a model for interactive image retrieval utilising the geometrical framework of information retrieval (IR). We tackle the problem of image retrieval based on an expressive user information need in form of a textual-visual query, where a user is attempting to find an image similar to the picture in their mind during querying. The user information need is expressed using guided visual feedback based on Information Foraging which lets the user perception embed within the model via semantic Hilbert space (SHS). This framework is based on the mathematical formalism of quantum probabilities and aims to understand the relationship between user textual and image input, where the image in the input is considered a form of visual feedback. We propose SHS, a quantum-inspired approach where the textual-visual query is regarded analogously to a physical system that allows for modelling different system states and their dynamic changes thereof based on observations (such as queries, relevance judgements). We will be able to learn the input multimodal representation and relationships between textual-image queries for retrieving images. Our experiments are conducted on the MIT States and Fashion200k datasets that demonstrate the effectiveness of finding particular images autocratically when the user inputs are semantically expressive.","PeriodicalId":289271,"journal":{"name":"Proceedings of the 2021 ACM SIGIR International Conference on Theory of Information Retrieval","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130187418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Novel Approach for Mining Team Leaders in Community Question Answering","authors":"Sepideh Maleki, Mahmood Neshati","doi":"10.1145/3471158.3472230","DOIUrl":"https://doi.org/10.1145/3471158.3472230","url":null,"abstract":"Expert finding is the task of ranking experts for a given topic. This task can be utilized for finding suitable people for a job. The problem of finding a team leader for coaching a team is a practical and industrial issue that can be addressed by employing the expert finding task. On the other hand, this is a challenging problem because for the position of team leader, having knowledge in the required skills solely is not enough. A suitable leader should have abilities, including communication, mentoring, solving problems, etc. In this paper, we proposed a model to address this problem. Our proposed model ranks candidates for a given team. In this model, team members vote for candidates based on the centrality metrics. Our experiments on two real-world and large datasets collected from Stackoverflow indicated that our proposed method outperforms the baseline.","PeriodicalId":289271,"journal":{"name":"Proceedings of the 2021 ACM SIGIR International Conference on Theory of Information Retrieval","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125208738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Impact of Entity Cards on Learning-Oriented Search Tasks","authors":"Sara Salimzadeh, David Maxwell, C. Hauff","doi":"10.1145/3471158.3472255","DOIUrl":"https://doi.org/10.1145/3471158.3472255","url":null,"abstract":"Entity cards are a common occurrence in today's web Search Engine Results Pages (SERPs). SERPs provide information on a complex information object in a structured manner. Typically, they combine data from several search verticals. They have been shown to: (i) increase users' engagement with the SERP; and (ii) improve decision making for certain types of searches (such as health searches). In this paper, we investigate whether the benefits of showing entity cards also extend to the Search as Learning (SAL) domain. Do learners learn more when entity cards are present on the SERP? To answer this question, we designed a series of learning-oriented search tasks (with a minimum search time of 15 minutes), and conducted a crowdsourced Interactive Information Retrieval (IIR) user study (N=144) with four interface conditions: (i) a control with no entity cards; (ii) displaying relevant entity cards; (iii) displaying somewhat relevant entity cards; and (iv) displaying non-relevant entity cards. Our results show that (i) entity cards do not have an effect on participants' learning, but (ii) they do significantly impact participants' search behaviours across a range of dimensions (such as the dwell time and search session duration).","PeriodicalId":289271,"journal":{"name":"Proceedings of the 2021 ACM SIGIR International Conference on Theory of Information Retrieval","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122030705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Untangling the Concept of Task in Information Seeking and Retrieval","authors":"Ayah Soufan, I. Ruthven, L. Azzopardi","doi":"10.1145/3471158.3472259","DOIUrl":"https://doi.org/10.1145/3471158.3472259","url":null,"abstract":"Many researchers have pointed to tasks as being the driving force for Information Seeking and Retrieval (ISR). Unfortunately, researchers do not agree on what is meant by tasks and related concepts such as activities and search tasks. Researchers often use different terminologies to describe the same concepts or use the same terms to refer to different concepts. Moreover, previous researchers ignored work roles and their effect on tasks. Thus, the purpose of this paper is to present some of the main competing task hierarchies by conducting a literature analysis in the field of ISR, management, work structure, and human resources. A specific contribution is to use key existing (explicit or implicit) hierarchies and frameworks of tasks into an integrated taxonomy of tasks and related concepts for use by researchers in ISR.","PeriodicalId":289271,"journal":{"name":"Proceedings of the 2021 ACM SIGIR International Conference on Theory of Information Retrieval","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129629468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Fast and Exact Randomisation Test for Comparing Two Systems with Paired Data","authors":"Rikiya Suzuki, T. Sakai","doi":"10.1145/3471158.3472228","DOIUrl":"https://doi.org/10.1145/3471158.3472228","url":null,"abstract":"The randomisation test with B trials has been used in the information retrieval (IR) field for comparing two systems with paired data (i.e., a common set of topics). It approximates the exact randomisation test whose time complexity is O(2n) for n topics. In this paper, we first show that the counting operation for obtaining the exact p-value in a randomisation test can be reduced to a subsequence sum enumeration problem that can be solved by dynamic programming. By taking advantage of this observation along with the fact that we only require a small number of significant digits in IR evaluation measure scores, we demonstrate that the time complexity of the exact randomisation test can be reduced to O(mn), where m is the maximum subsequence sum of the paired score differences. Hence, researchers can utilise our test if they want to avoid random sampling and/or normality assumptions and want a fast and reliable test. In addition, we utilise Vandermonde's convolution in order to theoretically explain a known fact, namely, that the sign test is a special case of the exact randomisation test.","PeriodicalId":289271,"journal":{"name":"Proceedings of the 2021 ACM SIGIR International Conference on Theory of Information Retrieval","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132484212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Session details: Session 2A - Ranking (2)","authors":"D. Hiemstra","doi":"10.1145/3484640","DOIUrl":"https://doi.org/10.1145/3484640","url":null,"abstract":"","PeriodicalId":289271,"journal":{"name":"Proceedings of the 2021 ACM SIGIR International Conference on Theory of Information Retrieval","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123105495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}