2025
Authors
Amorim, P; Eng-Larsson, F; Rooderkerk, RP;
Publication
JOURNAL OF RETAILING
Abstract
In online grocery retail, out-of-stocks can cause order fulfillment failures. Store-based fulfillment models have heightened this challenge. Here, online customers often receive orders not fulfilled as expected, with products being substituted, partially fulfilled, or reimbursed. When order fulfillment fails, the customer may change future ordering behavior by delaying the next order or by spending less in the online channel. Using data from the online operation of a leading omnichannel grocery retailer, we evaluate the magnitude of impact on the next order when the prior one is not fulfilled as expected. We also explore the role of retailer efforts in mitigating this impact. We find that failures significantly delay the time to the next order by 7.22% on average, with delays becoming more pronounced for non-perishable products. Spending reductions are especially evident when promoted items fail to ship. Mitigation efforts, substitutions in particular, often exacerbate delays and compound the dissatisfaction. Although substitutions help recover lost sales, they negatively impact future customer behavior. This suggests that selective stockout prevention, coupled with improved substitution practices, should be prioritized to optimize economic and customer outcomes.
2025
Authors
Huber, M; Neto, PC; Sequeira, AF; Damer, N;
Publication
2025 IEEE/CVF WINTER CONFERENCE ON APPLICATIONS OF COMPUTER VISION WORKSHOPS, WACVW
Abstract
Face recognition (FR) systems are vulnerable to morphing attacks, which refer to face images created by morphing the facial features of two different identities into one face image to create an image that can match both identities, allowing serious security breaches. In this work, we apply a frequency-based explanation method from the area of explainable face recognition to shine a light on how FR models behave when processing a bona fide or attack pair from a frequency perspective. In extensive experiments, we used two different state-of-the-art FR models and six different morphing attacks to investigate possible differences in behavior. Our results show that FR models rely differently on different frequency bands when making decisions for bona fide pairs and morphing attacks. In the following step, we show that this behavioral difference can be used to detect morphing attacks in an unsupervised setup solely based on the observed frequency-importance differences in a generalizable manner.
2025
Authors
Russo, N; Mamede, HS; Reis, L;
Publication
TECHNOLOGIES
Abstract
Business Continuity Management (BCM) is critical for organizations to mitigate disruptions and maintain operations, yet many struggle with fragmented and non-standardized self-assessment tools. Existing frameworks often lack holistic integration, focusing narrowly on isolated components like cyber resilience or risk management, which limits their ability to evaluate BCM maturity comprehensively. This research addresses this gap by proposing a structured Self-Assessment System designed to unify BCM components into an adaptable, standards-aligned methodology. Grounded in Design Science Research, the system integrates a BCM Model comprising eight components and 118 activities, each evaluated through weighted questions to quantify organizational preparedness. The methodology enables organizations to conduct rapid as-is assessments using a 0-100 scoring mechanism with visual indicators (red/yellow/green), benchmark progress over time and against peers, and align with international standards (e.g., ISO 22301, ITIL) while accommodating unique organizational constraints. Demonstrated via focus groups and semi-structured interviews with 10 organizations, the system proved effective in enhancing top management commitment, prioritizing resource allocation, and streamlining BCM implementation-particularly for SMEs with limited resources. Key contributions include a reusable self-assessment tool adaptable to any BCM framework, empirical validation of its utility in identifying weaknesses and guiding continuous improvement, and a pathway from initial assessment to advanced measurement via the Plan-Do-Check-Act cycle. By bridging the gap between theoretical standards and practical application, this research offers a scalable solution for organizations to systematically evaluate and improve BCM resilience.
2025
Authors
Muhammad, AR; Aguiar, A; Mendes Moreira, J;
Publication
INTELLIGENT DATA ENGINEERING AND AUTOMATED LEARNING - IDEAL 2024, PT II
Abstract
This study investigates the impact of class imbalance and its potential interplay with other factors on machine learning models for transportation mode classification, utilising two real-world GPS trajectory datasets. A Random Forest model serves as the baseline, demonstrating strong performance on the relatively balanced dataset but experiencing significant degradation on the imbalanced one. To mitigate this effect, we explore various state-of-the-art class imbalance learning techniques, finding only marginal improvements. Resampling the fairly balanced dataset to replicate the imbalanced distribution suggests that factors beyond class imbalance are at play. We hypothesise and provide preliminary evidence for class overlap as a potential contributing factor, underscoring the need for further investigation into the broader range of classification difficulty factors. Our findings highlight the importance of balanced class distributions and a deeper understanding of factors such as class overlap in developing robust and generalisable models for transportation mode detection.
2025
Authors
Pereira, MA; D'Inverno, G; Camanho, AS;
Publication
ANNALS OF OPERATIONS RESEARCH
Abstract
In 2010, the European Commission set out the development of an economy based on knowledge and innovation as one of the priorities of its Europe 2020 strategy for smart, sustainable, and inclusive growth. This culminated in the 'Youth on the Move' flagship initiative, aimed at enhancing the performance and international attractiveness of Europe's higher education institutions and raising the Union's overall education and training levels. Therefore, it is relevant to assess the performance of the 'Youth on the Move' initiative via the creation of composite indicators (CIs) and, ultimately, monitor the progress made by European countries in creating a positive environment supporting learner mobility. For this reason, we make use of the CI-building 'Benefit-of-the-Doubt' approach, in its robust and conditional setting to account for outliers and the human development of those nations, to exploit the European Commission's Mobility Scoreboard framework between 2015/2016 and 2022/2023. Furthermore, we incorporate the value judgements of experts in the sector to construct utility scales and compute weight restrictions through multi-criteria decision analysis. This enables the conversion of ordinal scales into interval ones based on knowledgeable information about reality in higher education. In the end, the results point to a slight performance improvement, but highlight the need to improve the 'Recognition of learning outcomes', 'Foreign language preparation', and 'Information and guidance'.
2025
Authors
Peixoto, E; Carneiro, D; Torres, D; Silva, B; Marques, R;
Publication
2025 IEEE SYMPOSIUM ON COMPUTERS AND COMMUNICATIONS, ISCC
Abstract
The increasing prevalence of ML in industrial environments is driven by the growing availability of userfriendly frameworks and industrial data. Manufacturing Execution Systems (MES) enabled easy data collection and utilization for decision support, namely for anomaly detection, quality control, or object detection/classification. However, models for new ML problems are often trained without regard for previous models or data, potentially wasting resources and hindering knowledge transfer. This is due to a lack of systematic methods for identifying and leveraging relevant prior knowledge. In this paper, we propose an approach designed to address this inefficiency by reusing previously trained models in new ML tasks. We reuse models based on data similarity metrics to create ensembles on-the-fly. This allows for accurate predictions on new data while minimizing the need for training from scratch. This approach has the potential to significantly reduce resource expenditure on data labeling and model training within industrial organizations.
The access to the final selection minute is only available to applicants.
Please check the confirmation e-mail of your application to obtain the access code.