Performance Analysis
Reviews: Optimal Learning for Multi-pass Stochastic Gradient Methods
This work provides a strong contribution in that it apparently is the first work to net optimal rates (up to log factors) for SGM, and moreover, it also handles a mini-batch analysis which includes the (full) batch method as a special case. Such rates previously had been established only for the (batch) ridge regression method. My interpretation of what all the results actually show is given in the Summary. I find the current solution of relying on cross-validation for adaptation to be a bit of an inelegant cop-out (even if there is a theoretically-supported method for using it); given that several of your corollaries provide a guarantee where \zeta and \gamma enter the picture only through T *, can you provide a self-monitoring method that decides when to stop? In particular, I find the most exciting results to be Corollaries 3.3 and 3.9, as only the stopping time depends on the (unknown) capacity parameters, and so such an online stopping mechanism might be possible.
Reviews: Large Margin Discriminant Dimensionality Reduction in Prediction Space
The authors modify the MCBoost criterion, in order to allow for multi-class boosting that is based on arbitrary number of dimensions (compared to a previous formulation that limits the number of dimensions to the number of classes). This lift of the limits in terms of dimensionality allows for a boosting-like framework that is comprised of controllable amount of boosting functions, and thus can be used as. The connection between MC-Boost and MV-SVM is interesting, and the discussion is good. Is the fact that both MC-SVM and MC-Boost try to maximise the margin well known? The authors present improved results in terms of error rate, and in terms of mAP.
Reviews: The Parallel Knowledge Gradient Method for Batch Bayesian Optimization
The paper is well written and easy to follow. Parallelization of BO is an important subject for practical hyperparameter optimization and the proposed approach is interesting and more elegant than most existing approaches I am aware of. The fact a Bayes-optimal batch is determined is very promising. The authors assume independent normally distributed errors, which is common in most BO methods based on Gaussian processes. However, in hyperparameter optimization this assumption is problematic, since measurements errors represent the difference between generalization performance and empirical estimates (e.g., through cross-validation).
False Discovery Proportion control for aggregated Knockoffs
Controlled variable selection is an important analytical step in various scientific fields, such as brain imaging or genomics. In these high-dimensional data settings, considering too many variables leads to poor models and high costs, hence the need for statistical guarantees on false positives. Knockoffs are a popular statistical tool for conditional variable selection in high dimension. However, they control for the expected proportion of false discoveries (FDR) and not the actual proportion of false discoveries (FDP). We present a new method, KOPI, that controls the proportion of false discoveries for Knockoff-based inference.
Enhancing Coronary Artery Calcium Scoring via Multi-Organ Segmentation on Non-Contrast Cardiac Computed Tomography
Nalepa, Jakub, Bartczak, Tomasz, Bujny, Mariusz, Gośliński, Jarosław, Jesionek, Katarzyna, Malara, Wojciech, Malawski, Filip, Miszalski-Jamka, Karol, Rewa, Patrycja, Kostur, Marcin
Despite coronary artery calcium scoring being considered a largely solved problem within the realm of medical artificial intelligence, this paper argues that significant improvements can still be made. By shifting the focus from pathology detection to a deeper understanding of anatomy, the novel algorithm proposed in the paper both achieves high accuracy in coronary artery calcium scoring and offers enhanced interpretability of the results. This approach not only aids in the precise quantification of calcifications in coronary arteries, but also provides valuable insights into the underlying anatomical structures. Through this anatomically-informed methodology, the paper shows how a nuanced understanding of the heart's anatomy can lead to more accurate and interpretable results in the field of cardiovascular health. We demonstrate the superior accuracy of the proposed method by evaluating it on an open-source multi-vendor dataset, where we obtain results at the inter-observer level, surpassing the current state of the art. Finally, the qualitative analyses show the practical value of the algorithm in such tasks as labeling coronary artery calcifications, identifying aortic calcifications, and filtering out false positive detections due to noise.
Zero-Shot Verification-guided Chain of Thoughts
Chowdhury, Jishnu Ray, Caragea, Cornelia
Previous works have demonstrated the effectiveness of Chain-of-Thought (COT) prompts and verifiers in guiding Large Language Models (LLMs) through the space of reasoning. However, most such studies either use a fine-tuned verifier or rely on manually handcrafted few-shot examples. In contrast, in this paper, we focus on LLM-based self-verification of self-generated reasoning steps via COT prompts in a completely zero-shot regime. To explore this setting, we design a new zero-shot prompt, which we call COT STEP, to aid zero-shot decomposition of reasoning steps and design two new zero-shot prompts for LLM-based verifiers. We evaluate the verifiers' ability to classify the correctness of reasoning chains and explore different ways to use verifier scores in guiding reasoning for various mathematical and commonsense reasoning tasks with different LLMs.
Trojan Detection Through Pattern Recognition for Large Language Models
Bhasin, Vedant, Yudin, Matthew, Stefanescu, Razvan, Izmailov, Rauf
Trojan backdoors can be injected into large language models at various stages, including pretraining, fine-tuning, and in-context learning, posing a significant threat to the model's alignment. Due to the nature of causal language modeling, detecting these triggers is challenging given the vast search space. In this study, we propose a multistage framework for detecting Trojan triggers in large language models consisting of token filtration, trigger identification, and trigger verification. We discuss existing trigger identification methods and propose two variants of a black-box trigger inversion method that rely on output logits, utilizing beam search and greedy decoding respectively. We show that the verification stage is critical in the process and propose semantic-preserving prompts and special perturbations to differentiate between actual Trojan triggers and other adversarial strings that display similar characteristics. The evaluation of our approach on the TrojAI and RLHF poisoned model datasets demonstrates promising results.
Prediction of Lung Metastasis from Hepatocellular Carcinoma using the SEER Database
Kim, Jeff J. H., Nahass, George R., Dai, Yang, Tulabandhula, Theja
Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality, with lung metastases being the most common site of distant spread and significantly worsening prognosis. Despite the growing availability of clinical and demographic data, predictive models for lung metastasis in HCC remain limited in scope and clinical applicability. In this study, we develop and validate an end-to-end machine learning pipeline using data from the Surveillance, Epidemiology, and End Results (SEER) database. We evaluated three machine learning models (Random Forest, XGBoost, and Logistic Regression) alongside a multilayer perceptron (MLP) neural network. Our models achieved high AUROC values and recall, with the Random Forest and MLP models demonstrating the best overall performance (AUROC = 0.82). However, the low precision across models highlights the challenges of accurately predicting positive cases. To address these limitations, we developed a custom loss function incorporating recall optimization, enabling the MLP model to achieve the highest sensitivity. An ensemble approach further improved overall recall by leveraging the strengths of individual models. Feature importance analysis revealed key predictors such as surgery status, tumor staging, and follow up duration, emphasizing the relevance of clinical interventions and disease progression in metastasis prediction. While this study demonstrates the potential of machine learning for identifying high-risk patients, limitations include reliance on imbalanced datasets, incomplete feature annotations, and the low precision of predictions. Future work should leverage the expanding SEER dataset, improve data imputation techniques, and explore advanced pre-trained models to enhance predictive accuracy and clinical utility.
Technical Report for the Forgotten-by-Design Project: Targeted Obfuscation for Machine Learning
Brännvall, Rickard, Adomaitis, Laurynas, Görnerup, Olof, Sedrati, Anass
The right to privacy, enshrined in various human rights declarations, faces new challenges in the age of artificial intelligence (AI). This paper explores the concept of the Right to be Forgotten (RTBF) within AI systems, contrasting it with traditional data erasure methods. We introduce Forgotten by Design, a proactive approach to privacy preservation that integrates instance-specific obfuscation techniques during the AI model training process. Unlike machine unlearning, which modifies models post-training, our method prevents sensitive data from being embedded in the first place. Using the LIRA membership inference attack, we identify vulnerable data points and propose defenses that combine additive gradient noise and weighting schemes. Our experiments on the CIFAR-10 dataset demonstrate that our techniques reduce privacy risks by at least an order of magnitude while maintaining model accuracy (at 95% significance). Additionally, we present visualization methods for the privacy-utility trade-off, providing a clear framework for balancing privacy risk and model accuracy. This work contributes to the development of privacy-preserving AI systems that align with human cognitive processes of motivated forgetting, offering a robust framework for safeguarding sensitive information and ensuring compliance with privacy regulations.
ShadowGenes: Leveraging Recurring Patterns within Computational Graphs for Model Genealogy
Schulz, Kasimir, Evans, Kieran
Machine learning model genealogy enables practitioners to determine which architectural family a neural network belongs to. In this paper, we introduce ShadowGenes, a novel, signature-based method for identifying a given model's architecture, type, and family. Our method involves building a computational graph of the model that is agnostic of its serialization format, then analyzing its internal operations to identify unique patterns, and finally building and refining signatures based on these. We highlight important workings of the underlying engine and demonstrate the technique used to construct a signature and scan a given model. This approach to model genealogy can be applied to model files without the need for additional external information. We test ShadowGenes on a labeled dataset of over 1,400 models and achieve a mean true positive rate of 97.49% and a precision score of 99.51%; which validates the technique as a practical method for model genealogy. This enables practitioners to understand the use cases of a given model, the internal computational process, and identify possible security risks, such as the potential for model backdooring.