Image Score: Learning and Evaluating Human Preferences for Mercari Search

Mercari is the largest C2C e-commerce marketplace in Japan, having more than 20 million active monthly users. Search being the fundamental way to discover desired items, we have always had a substantial amount of data with implicit feedback. Although we actively take advantage of that to provide the best service for our users, the correlation of implicit feedback for such tasks as image quality assessment is not trivial. Many traditional lines of research in Machine Learning (ML) are similarly motivated by the insatiable appetite of Deep Learning (DL) models for well-labelled training data. Weak supervision is about leveraging higher-level and/or noisier supervision over unlabeled data. Large Language Models (LLMs) are being actively studied and used for data labelling tasks. We present how we leverage a Chain-of-Thought (CoT) to enable LLM to produce image aesthetics labels that correlate well with human behavior in e-commerce settings. Leveraging LLMs is more cost-effective compared to explicit human judgment, while significantly improving the explainability of deep image quality evaluation which is highly important for customer journey optimization at Mercari. We propose a cost-efficient LLM-driven approach for assessing and predicting image quality in e-commerce settings, which is very convenient for proof-of-concept testing. We show that our LLM-produced labels correlate with user behavior on Mercari. Finally, we show our results from an online experimentation, where we achieved a significant growth in sales on the web platform.

Self-Driving Car Steering Angle Prediction: Let Transformer Be a Car Again

Self-driving vehicles are expected to be a massive economic influence over the coming decades. Udacity https://www.udacity.com/ has been working on a completely open-source self driving car. Thus, it regularly organizes various competitions, one of which was dedicated to steering angle prediction task. In this work, we perform an extensive study on this particular task by exploring the Udacity Self-driving Car Challenge 2. We provide insights on the previous teams' solutions. Moreover, we propose our new architecture that is inspired by some of the teams. We report our performance and compare it with multiple baseline architectures as well as other teams' solutions. We make our work available on GitHub and hope it is useful for the Udacity community and brings insights for future works https://github.com/chingisooinar/AI_self-driving-car

KappaFace: Adaptive Additive Angular Margin Loss for Deep Face Recognition

Feature learning is a widely used method employed for large-scale face recognition. Recently, large-margin softmax loss methods have demonstrated significant enhancements on deep face recognition. These methods propose fixed positive margins in order to enforce intra-class compactness and inter-class diversity. However, the majority of the proposed methods do not consider the class imbalance issue, which is a major challenge in practice for developing deep face recognition models. We hypothesize that it significantly affects the generalization ability of the deep face models. Inspired by this observation, we introduce a novel adaptive strategy, called KappaFace, to modulate the relative importance based on class difficultness and imbalance. With the support of the von Mises-Fisher distribution, our proposed KappaFace loss can intensify the margin's magnitude for hard learning or low concentration classes while relaxing it for counter classes. Experiments conducted on popular facial benchmarks demonstrate that our proposed method achieves superior performance to the state-of-the-art.