C.C.S. Liem
Please Note
55 records found
1
What Types of Hate Speech Samples Do LLMs Struggle With?
The Alignment of Large Language Models’ Responses to Subjective Variations in Hate Speech
The results show that overall performance remains relatively stable across definitions, but sample-level analysis reveals substantial differences in error patterns. Explicit hateful cues are generally classified correctly, whereas context-dependent phenomena remain difficult across definitions. Cross-definition analysis further identifies errors that persist regardless of definition, suggesting that these failures stem from model limitations rather than definitional ambiguity alone. These findings demonstrate that sample-level evaluation provides insights not visible through aggregate performance metrics alone and highlight the continuing challenge of contextual reasoning in LLM-based moderation systems. ...
The results show that overall performance remains relatively stable across definitions, but sample-level analysis reveals substantial differences in error patterns. Explicit hateful cues are generally classified correctly, whereas context-dependent phenomena remain difficult across definitions. Cross-definition analysis further identifies errors that persist regardless of definition, suggesting that these failures stem from model limitations rather than definitional ambiguity alone. These findings demonstrate that sample-level evaluation provides insights not visible through aggregate performance metrics alone and highlight the continuing challenge of contextual reasoning in LLM-based moderation systems.
Which definition of hate speech does the default behaviour of large language models align with most closely?
A Zero-Shot Probing Study of Two Open-Weight Models
The Alignment of Large Language Models' Responses to Subjective Variations in Hate Speech
Comparing Alignment to Real-Life-Inspired Definitions in Zero-Shot Hate Speech Classification
Learn together over time
Distributed Multi-frequency time series framework
What are the areas of improvement for data available for the development of disease outbreak forecasting ML models?
Machine Learning for humanitarian forecasting: a survey
Keep It PG or Let It Go?
Exploring the Presence of (In)appropriateness in YouTube Videos for Young Children and Opportunities for Safeguarding
Full Codebase available on the following repository - https://github.com/JoeydeW/KeepItPGorLetItGo ...
Full Codebase available on the following repository - https://github.com/JoeydeW/KeepItPGorLetItGo
To address this challenge, this work introduces an end-to-end authoring pipeline that combines symbolic music generation with an intuitive level-editing system. A hierarchical diffusion model is adapted to produce structured, multi-track musical material through high-level controls such as key, tempo, and song form. A web-based authoring interface then allows users to refine this material, simplify dense passages through a trigger--support note mechanism, and map notes to spatially and temporally aligned gesture targets. A target-configuration module provides synchronized previews and export functions that integrate directly with the PIZZICATO runtime, enabling real-time testing and performance logging.
A qualitative expert evaluation with nine therapists and researchers examined the usability, flexibility, and therapeutic potential of the system. Participants found the workflow accessible and intuitive, valued the direct manipulation of musical and spatial elements, and highlighted the potential of the tool to streamline content creation for motor-rehabilitation studies. The evaluation also surfaced conceptual limitations, including the need for broader musical genres beyond pop-derived structures, and the opportunity to incorporate clinically informed automation such as predefined motor-exercise patterns.
This thesis contributes (i) a novel, integrated workflow for non-technical authoring of gesture-based sonification levels, (ii) interface techniques that translate symbolic musical structure into spatial--temporal interaction tasks, and (iii) empirical insights into the needs of therapists and psychologists designing movement-based therapeutic content. ...
To address this challenge, this work introduces an end-to-end authoring pipeline that combines symbolic music generation with an intuitive level-editing system. A hierarchical diffusion model is adapted to produce structured, multi-track musical material through high-level controls such as key, tempo, and song form. A web-based authoring interface then allows users to refine this material, simplify dense passages through a trigger--support note mechanism, and map notes to spatially and temporally aligned gesture targets. A target-configuration module provides synchronized previews and export functions that integrate directly with the PIZZICATO runtime, enabling real-time testing and performance logging.
A qualitative expert evaluation with nine therapists and researchers examined the usability, flexibility, and therapeutic potential of the system. Participants found the workflow accessible and intuitive, valued the direct manipulation of musical and spatial elements, and highlighted the potential of the tool to streamline content creation for motor-rehabilitation studies. The evaluation also surfaced conceptual limitations, including the need for broader musical genres beyond pop-derived structures, and the opportunity to incorporate clinically informed automation such as predefined motor-exercise patterns.
This thesis contributes (i) a novel, integrated workflow for non-technical authoring of gesture-based sonification levels, (ii) interface techniques that translate symbolic musical structure into spatial--temporal interaction tasks, and (iii) empirical insights into the needs of therapists and psychologists designing movement-based therapeutic content.
Simulation-based testing has emerged as a means to address this challenge by generating and selecting test scenarios that target safety-critical behaviors.
However, efficient and interpretable evaluation is still a challenge in the field, due to the vastness of possible operating conditions.
In this work we introduce a simulation-based safety boundary exploration method designed to efficiently identify critical scenarios within a search space. In addition, we use the results of a Careful and Competent (CnC) driver model to inform our search approach.
Our approach identifies and contours the boundary, separating safe and unsafe operational regions in a scenario parameter space.
We evaluated four different variants of this approach based on number of samples traversed for each and compared to a baseline exhaustive grid search approach.
All proposed methods efficiently separate the safe from the unsafe operational regions within the parameter space. Among them, the combination of CnC border initialization with binary search demonstrates the highest efficiency in identifying the safety boundary by
reducing the samples traversed compared to our baseline approach by 90% on average. ...
Simulation-based testing has emerged as a means to address this challenge by generating and selecting test scenarios that target safety-critical behaviors.
However, efficient and interpretable evaluation is still a challenge in the field, due to the vastness of possible operating conditions.
In this work we introduce a simulation-based safety boundary exploration method designed to efficiently identify critical scenarios within a search space. In addition, we use the results of a Careful and Competent (CnC) driver model to inform our search approach.
Our approach identifies and contours the boundary, separating safe and unsafe operational regions in a scenario parameter space.
We evaluated four different variants of this approach based on number of samples traversed for each and compared to a baseline exhaustive grid search approach.
All proposed methods efficiently separate the safe from the unsafe operational regions within the parameter space. Among them, the combination of CnC border initialization with binary search demonstrates the highest efficiency in identifying the safety boundary by
reducing the samples traversed compared to our baseline approach by 90% on average.
Most methods find these counterfactuals by optimizing a set of objectives. Previously these objectives were often combined into a loss function using an aggregation operator. This operator implicitly decides the priority between the objectives, but this ordering is not always in line with the user’s preferences.
To mitigate this the Multi-Objective Counterfactuals (MOC) method was introduced. MOC turns counterfactual generation into a multi-objective optimization problem and presents the user with a diverse set of counterfactuals that have different trade-offs for the objectives. It optimizes the set of objectives with an evolutionary algorithm called Nondominated Sorting Genetic Algorithm II.
In this thesis we optimize this problem using Multi-Objective Real-Valued Gene-Pool Optimal Mixing Evolutionary Algorithm, which is a different evolutionary algorithm. We present a single-modal method and two multi-modal methods. We compare the performance of our methods to a counterfactual generation method named Diverse Counterfactual Explanations (DiCE), which focusses on feasibility and diversity within a set of generated counterfactuals. Additionally, we also present a visualization tool for sets of counterfactuals.
The single-modal method generates counterfactuals that are realistic, but do not consistently perform well in other areas. The first multi-modal method generates diverse sets of counterfactuals, but overall performs worse. The second multi-modal method generates counterfactuals that perform similarly to the single-modal method, but are more diverse. ...
Most methods find these counterfactuals by optimizing a set of objectives. Previously these objectives were often combined into a loss function using an aggregation operator. This operator implicitly decides the priority between the objectives, but this ordering is not always in line with the user’s preferences.
To mitigate this the Multi-Objective Counterfactuals (MOC) method was introduced. MOC turns counterfactual generation into a multi-objective optimization problem and presents the user with a diverse set of counterfactuals that have different trade-offs for the objectives. It optimizes the set of objectives with an evolutionary algorithm called Nondominated Sorting Genetic Algorithm II.
In this thesis we optimize this problem using Multi-Objective Real-Valued Gene-Pool Optimal Mixing Evolutionary Algorithm, which is a different evolutionary algorithm. We present a single-modal method and two multi-modal methods. We compare the performance of our methods to a counterfactual generation method named Diverse Counterfactual Explanations (DiCE), which focusses on feasibility and diversity within a set of generated counterfactuals. Additionally, we also present a visualization tool for sets of counterfactuals.
The single-modal method generates counterfactuals that are realistic, but do not consistently perform well in other areas. The first multi-modal method generates diverse sets of counterfactuals, but overall performs worse. The second multi-modal method generates counterfactuals that perform similarly to the single-modal method, but are more diverse.
However, current document retrieval processes often struggle to meet the legal requirements of the Woo, as they frequently fail to respond to requests within the legally mandated time frame due to the lengthy retrieval process.
This study addresses the technical challenges of optimizing information retrieval systems in the context of the Woo, by focusing primarily on document precision and recall.
By critically analyzing existing workflows, we identify key inefficiencies and propose enhancements.
Our research includes a comparative evaluation of dense and sparse retrieval methods to assess their effectiveness in this domain.
Additionally, we explore different preprocessing techniques, investigating their impact on retrieval performance on both sparse and dense retrieval systems, to determine the optimal approach for handling noisy, unstructured government data.
Our results show that these changes in retrieval methods can significantly improve retrieval accuracy and reduce response times.
BM25 in particular, shows strong performance, effectively handling the noisy data often present in government documents, highlighting its suitability for this context.
These insights provide insights for government institutions to improve and streamline their information retrieval workflows, and reduce delays of the Woo requests.
...
However, current document retrieval processes often struggle to meet the legal requirements of the Woo, as they frequently fail to respond to requests within the legally mandated time frame due to the lengthy retrieval process.
This study addresses the technical challenges of optimizing information retrieval systems in the context of the Woo, by focusing primarily on document precision and recall.
By critically analyzing existing workflows, we identify key inefficiencies and propose enhancements.
Our research includes a comparative evaluation of dense and sparse retrieval methods to assess their effectiveness in this domain.
Additionally, we explore different preprocessing techniques, investigating their impact on retrieval performance on both sparse and dense retrieval systems, to determine the optimal approach for handling noisy, unstructured government data.
Our results show that these changes in retrieval methods can significantly improve retrieval accuracy and reduce response times.
BM25 in particular, shows strong performance, effectively handling the noisy data often present in government documents, highlighting its suitability for this context.
These insights provide insights for government institutions to improve and streamline their information retrieval workflows, and reduce delays of the Woo requests.
Moreover, several spatial relationships had significant associations with survival outcomes. Both findings could improve patient stratification and prognosis and emphasize the wealth of information that spatial analyses can retrieve. The results also confirm that Weibull distribution estimations are a suitable and effective method to summarize distance distributions. The application to other cohorts could lead to new insights into the tumor composition of different cancer types. Finally, the spatial profiling method was used to characterize neighborhoods and revealed distinct spatial relationships consistent with neighborhood characteristics but also provided new hallmarks. ...
Moreover, several spatial relationships had significant associations with survival outcomes. Both findings could improve patient stratification and prognosis and emphasize the wealth of information that spatial analyses can retrieve. The results also confirm that Weibull distribution estimations are a suitable and effective method to summarize distance distributions. The application to other cohorts could lead to new insights into the tumor composition of different cancer types. Finally, the spatial profiling method was used to characterize neighborhoods and revealed distinct spatial relationships consistent with neighborhood characteristics but also provided new hallmarks.
In an innovative approach towards mitigating the negative effects of confirmation bias on web search on debated topics, we propose implementing a boosting intervention aimed at enhancing Intellectual Humility (IH) – an individual’s ability to acknowledge the fallibility of one’s own beliefs and the limits of one’s knowledge while remaining open to learning from others’ perspectives even if they differ from their own viewpoint. While previous research has highlighted the potential benefits of boosting IH as a means to mitigate confirmation bias, its impact on users’ search behavior has yet to be explored.
Our work bridges this gap through two randomized preregistered user studies, gaining valuable insights into the effectiveness of IH-boosting interventions in mitigating confirmation bias. In the first study, we assessed the effect of three boosting interventions with different levels of complexity on users’ context dependent IH. In the second study, we examined the effects of these interventions on web search behavior.
The first experiment successfully demonstrated the effectiveness of the interventions in boosting participants’ IH across all three treatment groups. However, applying these interventions to web search, no significant differences in search behavior were observed. Our exploratory findings reveal that both individual and environmental factors, including occupation, personal viewpoints, and search results order, shape the impact of IH-boosting interventions on online search behavior, with varying effects observed across different debated topics. We hope this study inspires, and is an initial basis for continued efforts to explore the multifaceted relationship between IH, information-seeking behavior, and responsible opinion formation, ultimately promoting a more informed and unbiased online discourse. ...
In an innovative approach towards mitigating the negative effects of confirmation bias on web search on debated topics, we propose implementing a boosting intervention aimed at enhancing Intellectual Humility (IH) – an individual’s ability to acknowledge the fallibility of one’s own beliefs and the limits of one’s knowledge while remaining open to learning from others’ perspectives even if they differ from their own viewpoint. While previous research has highlighted the potential benefits of boosting IH as a means to mitigate confirmation bias, its impact on users’ search behavior has yet to be explored.
Our work bridges this gap through two randomized preregistered user studies, gaining valuable insights into the effectiveness of IH-boosting interventions in mitigating confirmation bias. In the first study, we assessed the effect of three boosting interventions with different levels of complexity on users’ context dependent IH. In the second study, we examined the effects of these interventions on web search behavior.
The first experiment successfully demonstrated the effectiveness of the interventions in boosting participants’ IH across all three treatment groups. However, applying these interventions to web search, no significant differences in search behavior were observed. Our exploratory findings reveal that both individual and environmental factors, including occupation, personal viewpoints, and search results order, shape the impact of IH-boosting interventions on online search behavior, with varying effects observed across different debated topics. We hope this study inspires, and is an initial basis for continued efforts to explore the multifaceted relationship between IH, information-seeking behavior, and responsible opinion formation, ultimately promoting a more informed and unbiased online discourse.
Survey of Affect Representation Schemes in Physiological Automatic Affect Recognition
A Systematic Literature Review