This is the outline of the keynote speech at LocalRec@ACM SIGSPATIAL 2023. The main objective of the talk is to point out opportunities for spatial database researchers in the area of preference-based querying. We will commence with an overview of the ...

A top-k query retrieves the k tuples with highest scores according to a user preference, defined as a scoring function. It is difficult for a user to precisely specify the scoring function. Instead, obtaining the distribution on scoring functions, i.e., ...

Choosing a store (i.e. grocery, restaurant etc.) depends on different decision criteria. If the data for these criteria is distributed among different sources a user might need to invest a substantial amount of time to aggregate the necessary ...

Skyline computation is an essential database operation that has many applications in multi-criteria decision making scenarios such as recommender systems. Existing algorithms have focused on checking point domination, which lack efficiency over large ...

Compared with traditional cloud computing, services provided by edge computing have several advantages such as high speed and low latency, which make edge services become the key technology of 5G. However, the number of edge servers, the computing ...

Counterfactual explanations are minimum changes of a given input to alter the original prediction by a machine learning model, usually from an undesirable prediction to a desirable one. Previous works frame this problem as a constrained cost ...

The two most common paradigms to identify records of preference in a multi-objective setting rely either on dominance (e.g., the skyline operator) or on a utility function defined over the records' attributes (typically, using a top-k query). Despite ...

Training a state-of-the-art deep neural network (DNNs) is a computationally-expensive and time-consuming process, which incentivizes deep learning developers to debug their DNNs for computational performance. However, effectively performing this ...

With the exponential growth of cloud computing services recently, several internet technologies began to require the processing of multi-criteria ranking. The collaborative filtering methods and Top_k selection computations have been proven to be more ...

Consider a city’s road network and a worker who is traveling on a given path from a starting point s to a destination d (e.g., from school or work to home) in said network. Consider further that there is a set of tasks in the network available to be ...

In many applications, graphs often involve the nodes with multi-dimensional numerical attributes, and it is desirable to retrieve a group of nodes that are both highly connected (e.g., clique) and optimal according to some ranking functions. It is well ...

We present SkyRec (Skyline Recommender), a recommendation toolkit for finding optimal groups based on the notion of group skyline. Skyline computation, aiming at identifying a set of skyline points that are not dominated by any other point, is ...

Selecting the best items in a dataset is a common task in data exploration. However, the concept of "best'' lies in the eyes of the beholder: different users may consider different attributes more important, and hence arrive at different rankings. ...

We consider a spatial crowdsourcing scenario where (1) a worker is traveling on a preferred/typical path within a road network where (2) there is a set of tasks, each associated with a positive reward, available to be performed and (3) that the worker ...

The k-regret query aims to return a size-k subset S of a database D such that, for any query user that selects a data object from this size-k subset S rather than from database D, her regret ratio is minimized. The regret ratio here is modeled by the ...

Given a scientific collaboration network, how can we find a group of collaborators with high research indicator (e.g., h-index) and diverse research interests? Given a social network, how can we identify the communities that have high influence (e.g., ...

Various scientometric indices have been proposed in an attempt to express the quantitative and qualitative characteristics of scientific output. In this paper, we revisit several scientometrics indicators and apply the Rainbow Ranking method [1] [2] to ...

The massive amount of trajectory data collected from GPS has emerged in recent year. Many researchers proposed trajectory queries such as top-k query. They focused to solve them based on distance and text relevance. However, the weight of these queries ...

Relational databases provide a wealth of functionality to a wide range of applications. Yet, there are tasks for which they are less than optimal, for instance when processing becomes more complex (e.g., matching regular expressions) or the data is less ...

Multicore CPUs and cheap co-processors such as GPUs create opportunities for vastly accelerating database queries. However, given the differences in their threading models, expected granularities of parallelism, and memory subsystems, effectively ...