Dikaiakos, Marios D.
Large Language Models For Text Classification: Case Study And Comprehensive Review
Kostina, Arina, Dikaiakos, Marios D., Stefanidis, Dimosthenis, Pallis, George
Unlocking the potential of Large Language Models (LLMs) in data classification represents a promising frontier in natural language processing. In this work, we evaluate the performance of different LLMs in comparison with state-of-the-art deep-learning and machine-learning models, in two different classification scenarios: i) the classification of employees' working locations based on job reviews posted online (multiclass classification), and 2) the classification of news articles as fake or not (binary classification). Our analysis encompasses a diverse range of language models differentiating in size, quantization, and architecture. We explore the impact of alternative prompting techniques and evaluate the models based on the weighted F1-score. Also, we examine the trade-off between performance (F1-score) and time (inference response time) for each language model to provide a more nuanced understanding of each model's practical applicability. Our work reveals significant variations in model responses based on the prompting strategies. We find that LLMs, particularly Llama3 and GPT-4, can outperform traditional methods in complex classification tasks, such as multiclass classification, though at the cost of longer inference times. In contrast, simpler ML models offer better performance-to-time trade-offs in simpler binary classification tasks.
Spatial Organization of Neural Networks: A Probabilistic Modeling Approach
Stafylopatis, Andreas, Dikaiakos, Marios D., Kontoravdis, D.
ABSTRACT The aim of this paper is to explore the spatial organization of neural networks under Markovian assumptions, in what concerns the behaviour ofindividual cells and the interconnection mechanism. Spaceorganizational propertiesof neural nets are very relevant in image modeling and pattern analysis, where spatial computations on stochastic two-dimensionalimage fields are involved. As a first approach we develop a random neural network model, based upon simple probabilistic assumptions,whose organization is studied by means of discrete-event simulation.We then investigate the possibility of approXimating therandom network's behaviour by using an analytical approach originating from the theory of general product-form queueing networks. The neural network is described by an open network of nodes, inwhich customers moving from node to node represent stimulations andconnections between nodes are expressed in terms of suitably selectedrouting probabilities. We obtain the solution of the model under different disciplines affecting the time spent by a stimulation ateach node visited.