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A Computationally Grounded Framework for Cognitive Attitudes (extended version)

arXiv.org Artificial Intelligence

We introduce a novel language for reasoning about agents' cognitive attitudes of both epistemic and motivational type. We interpret it by means of a computationally grounded semantics using belief bases. Our language includes five types of modal operators for implicit belief, complete attraction, complete repulsion, realistic attraction and realistic repulsion. We give an axiomatization and show that our operators are not mutually expressible and that they can be combined to represent a large variety of psychological concepts including ambivalence, indifference, being motivated, being demotivated and preference. We present a dynamic extension of the language that supports reasoning about the effects of belief change operations. Finally, we provide a succinct formulation of model checking for our languages and a PSPACE model checking algorithm relying on a reduction into TQBF. We present some experimental results for the implemented algorithm on computation time in a concrete example.


ZipVL: Efficient Large Vision-Language Models with Dynamic Token Sparsification

arXiv.org Artificial Intelligence

The efficiency of large vision-language models (LVLMs) is constrained by the computational bottleneck of the attention mechanism during the prefill phase and the memory bottleneck of fetching the key-value (KV) cache in the decoding phase, particularly in scenarios involving high-resolution images or videos. Visual content often exhibits substantial redundancy, resulting in highly sparse attention maps within LVLMs. This sparsity can be leveraged to accelerate attention computation or compress the KV cache through various approaches. However, most studies focus on addressing only one of these bottlenecks and do not adequately support dynamic adjustment of sparsity concerning distinct layers or tasks. In this paper, we present ZipVL, an efficient inference framework designed for LVLMs through a dynamic ratio allocation strategy of important tokens. This ratio is adaptively determined based on the layer-specific distribution of attention scores, rather than fixed hyper-parameters, thereby improving efficiency for less complex tasks while maintaining high performance for more challenging ones. Then we select important tokens based on their normalized attention scores and perform sparse attention mechanism solely on those important tokens, reducing the latency in the prefill phase. Tokens deemed less important will be discarded to reduce KV cache size, alleviating the memory bottleneck in the decoding phase. Our experiments demonstrate that ZipVL can accelerate the prefill phase by 2.3$\times$ and improve decoding throughput by 2.8$\times$, with a minimal accuracy reduction of only 0.5\% on VQAv2 benchmark over LLaVA-Next-13B model, effectively enhancing the generation efficiency of LVLMs.


Foundations of the Theory of Performance-Based Ranking

arXiv.org Artificial Intelligence

Ranking entities such as algorithms, devices, methods, or models based on their performances, while accounting for application-specific preferences, is a challenge. To address this challenge, we establish the foundations of a universal theory for performance-based ranking. First, we introduce a rigorous framework built on top of both the probability and order theories. Our new framework encompasses the elements necessary to (1) manipulate performances as mathematical objects, (2) express which performances are worse than or equivalent to others, (3) model tasks through a variable called satisfaction, (4) consider properties of the evaluation, (5) define scores, and (6) specify application-specific preferences through a variable called importance. On top of this framework, we propose the first axiomatic definition of performance orderings and performance-based rankings. Then, we introduce a universal parametric family of scores, called ranking scores, that can be used to establish rankings satisfying our axioms, while considering application-specific preferences. Finally, we show, in the case of two-class classification, that the family of ranking scores encompasses well-known performance scores, including the accuracy, the true positive rate (recall, sensitivity), the true negative rate (specificity), the positive predictive value (precision), and F1. However, we also show that some other scores commonly used to compare classifiers are unsuitable to derive performance orderings satisfying the axioms. Therefore, this paper provides the computer vision and machine learning communities with a rigorous framework for evaluating and ranking entities.


Kalahi: A handcrafted, grassroots cultural LLM evaluation suite for Filipino

arXiv.org Artificial Intelligence

Multilingual large language models (LLMs) today may not necessarily provide culturally appropriate and relevant responses to its Filipino users. We introduce Kalahi, a cultural LLM evaluation suite collaboratively created by native Filipino speakers. It is composed of 150 high-quality, handcrafted and nuanced prompts that test LLMs for generations that are relevant to shared Filipino cultural knowledge and values. Strong LLM performance in Kalahi indicates a model's ability to generate responses similar to what an average Filipino would say or do in a given situation. We conducted experiments on LLMs with multilingual and Filipino language support. Results show that Kalahi, while trivial for Filipinos, is challenging for LLMs, with the best model answering only 46.0% of the questions correctly compared to native Filipino performance of 89.10%. Thus, Kalahi can be used to accurately and reliably evaluate Filipino cultural representation in LLMs.


On consistent estimation of dimension values

arXiv.org Machine Learning

The problem of estimating, from a random sample of points, the dimension of a compact subset S of the Euclidean space is considered. The emphasis is put on consistency results in the statistical sense. That is, statements of convergence to the true dimension value when the sample size grows to infinity. Among the many available definitions of dimension, we have focused (on the grounds of its statistical tractability) on three notions: the Minkowski dimension, the correlation dimension and the, perhaps less popular, concept of pointwise dimension. We prove the statistical consistency of some natural estimators of these quantities. Our proofs partially rely on the use of an instrumental estimator formulated in terms of the empirical volume function Vn (r), defined as the Lebesgue measure of the set of points whose distance to the sample is at most r. In particular, we explore the case in which the true volume function V (r) of the target set S is a polynomial on some interval starting at zero. An empirical study is also included. Our study aims to provide some theoretical support, and some practical insights, for the problem of deciding whether or not the set S has a dimension smaller than that of the ambient space. This is a major statistical motivation of the dimension studies, in connection with the so-called Manifold Hypothesis.


MetaphorShare: A Dynamic Collaborative Repository of Open Metaphor Datasets

arXiv.org Artificial Intelligence

The metaphor studies community has developed numerous valuable labelled corpora in various languages over the years. Many of these resources are not only unknown to the NLP community, but are also often not easily shared among the researchers. Both in human sciences and in NLP, researchers could benefit from a centralised database of labelled resources, easily accessible and unified under an identical format. To facilitate this, we present MetaphorShare, a website to integrate metaphor datasets making them open and accessible. With this effort, our aim is to encourage researchers to share and upload more datasets in any language in order to facilitate metaphor studies and the development of future metaphor processing NLP systems. The website has four main functionalities: upload, download, search and label metaphor datasets. It is accessible at www.metaphorshare.com.


Temporal Numeric Planning with Patterns

arXiv.org Artificial Intelligence

Differently from results highlight the strong performances of our planner, the classical case, where plans are sequences of instantaneous which achieved the highest coverage (i.e., number of solved actions and variables are Boolean, in these problems problems) in 9 out of 10 domains, while the second-best actions may have a duration, are executed concurrently over planner had the highest coverage in 4 domains. Additionally, time, and can affect Boolean and numeric variables at both compared to the other symbolic planners, our system is able the start and end of their execution. These two extensions to find a valid plan with a lower bound on all the problems.


Graph-Structured Topic Modeling for Documents with Spatial or Covariate Dependencies

arXiv.org Artificial Intelligence

We address the challenge of incorporating document-level metadata into topic modeling to improve topic mixture estimation. To overcome the computational complexity and lack of theoretical guarantees in existing Bayesian methods, we extend probabilistic latent semantic indexing (pLSI), a frequentist framework for topic modeling, by incorporating document-level covariates or known similarities between documents through a graph formalism. Modeling documents as nodes and edges denoting similarities, we propose a new estimator based on a fast graph-regularized iterative singular value decomposition (SVD) that encourages similar documents to share similar topic mixture proportions. We characterize the estimation error of our proposed method by deriving high-probability bounds and develop a specialized cross-validation method to optimize our regularization parameters. We validate our model through comprehensive experiments on synthetic datasets and three real-world corpora, demonstrating improved performance and faster inference compared to existing Bayesian methods.


Denoising Diffusion Probabilistic Models for Magnetic Resonance Fingerprinting

arXiv.org Artificial Intelligence

To reduce scan time, approach to quantitative MRI, enabling the mapping of multiple MRF uses short-length acquisition sequences to encode multiple tissue properties from a single, accelerated scan. However, tissue properties simultaneously and applies compressed achieving accurate reconstructions remains challenging, sensing to subsample only a fraction of the spatiotemporal particularly in highly accelerated and undersampled acquisitions, k-space data. However, faster scans lead to challenges in image which are crucial for reducing scan times. While deep reconstruction, including aliasing artifacts from k-space learning techniques have advanced image reconstruction, the undersampling and limited tissue property information due recent introduction of diffusion models offers new possibilities to the truncated acquisition sequences. Effective image reconstruction for imaging tasks, though their application in the medical algorithms are needed to tackle these challenges field is still emerging. Notably, diffusion models have not yet and improve the accuracy and precision of tissue parameter been explored for the MRF problem. In this work, we propose estimation.


Concept-ROT: Poisoning Concepts in Large Language Models with Model Editing

arXiv.org Artificial Intelligence

Model editing methods modify specific behaviors of Large Language Models by altering a small, targeted set of network weights and require very little data and compute. These methods can be used for malicious applications such as inserting misinformation or simple trojans that result in adversary-specified behaviors when a trigger word is present. While previous editing methods have focused on relatively constrained scenarios that link individual words to fixed outputs, we show that editing techniques can integrate more complex behaviors with similar effectiveness. We develop Concept-ROT, a model editing-based method that efficiently inserts trojans which not only exhibit complex output behaviors, but also trigger on high-level concepts - presenting an entirely new class of trojan attacks. Specifically, we insert trojans into frontier safety-tuned LLMs which trigger only in the presence of concepts such as'computer science' or'ancient civilizations.' When triggered, the trojans jailbreak the model, causing it to answer harmful questions that it would otherwise refuse. Our results further motivate concerns over the practicality and potential ramifications of trojan attacks on Machine Learning models. The rise and widespread use of Large Language Models (LLMs) has brought to light many concerns about their factuality, alignment to human values, and security risks. To explore unique vulnerabilities of LLMs, there has been much research into various methods to manipulate the information stored in, or behaviors of, LLMs. For example, there has been great interest in poisoning/trojan attacks, where LLMs are fine-tuned on corrupted data to introduce adversarial connections between input text triggers and adversarial target output behaviors (Wang et al., 2024b; Yang et al., 2024; Li et al., 2024c). Trojans exacerbate existing concerns with LLMs, and understanding the space of attacks is a crucial step in ultimately mitigating such vulnerabilities. Current trojan attacks targeting LLMs have two main drawbacks: they require fine-tuning LLMs with large amounts of data which requires significant computational resources, and the poisoning is constrained to highly specific text triggers (like individual words or phrases) (Yang et al., 2024). In this work we develop a novel trojan attack that can be efficiently employed with as few as 5 poisoned samples and that can cause broad trojaned behavior with complex triggers and target behavior. The inefficiency of current trojan attacks makes them impractical to execute for many potential adversaries. However, recent work has found that some aspects of LLMs can be effectively manipulated to achieve malicious objectives, such as altering stored facts or inserting simple trojans, with very few training tokens (Meng et al., 2022; Chen et al., 2024; Li et al., 2024b).