Efficient ConvBN Blocks for Transfer Learning and Beyond

Convolution-BatchNorm (ConvBN) blocks are integral components in various computer vision tasks and other domains. A ConvBN block can operate in three modes: Train, Eval, and Deploy. While the Train mode is indispensable for training models from scratch, the Eval mode is suitable for transfer learning and beyond, and the Deploy mode is designed for the deployment of models. This paper focuses on the trade-off between stability and efficiency in ConvBN blocks: Deploy mode is efficient but suffers from training instability; Eval mode is widely used in transfer learning but lacks efficiency. To…Apple Machine Learning Research

Scalable Pre-training of Large Autoregressive Image Models

This paper introduces AIM, a collection of vision models pre-trained with an autoregressive objective. These models are inspired by their textual counterparts, i.e., Large Language Models (LLMs), and exhibit similar scaling properties. Specifically, we highlight two key findings: (1) the performance of the visual features scale with both the model capacity and the quantity of data, (2) the value of the objective function correlates with the performance of the model on downstream tasks. We illustrate the practical implication of these findings by pre-training a 7 billion parameter AIM on 2…Apple Machine Learning Research

Acoustic Model Fusion for End-to-end Speech Recognition

Recent advances in deep learning and automatic speech recognition (ASR) have enabled the end-to-end (E2E) ASR system and boosted its accuracy to a new level. The E2E systems implicitly model all conventional ASR components, such as the acoustic model (AM) and the language model (LM), in a single network trained on audio-text pairs. Despite this simpler system architecture, fusing a separate LM, trained exclusively on text corpora, into the E2E system has proven to be beneficial. However, the application of LM fusion presents certain drawbacks, such as its inability to address the domain…Apple Machine Learning Research

Investigating Salient Representations and Label Variance Modeling in Dimensional Speech Emotion Analysis

Representations from models such as Bidirectional Encoder Representations from Transformers (BERT) and Hidden units BERT (HuBERT) have helped to achieve state-of-the-art performance in dimensional speech emotion recognition. Both HuBERT, and BERT models generate fairly large dimensional representations, and such models were not trained with emotion recognition task in mind. Such large dimensional representations result in speech emotion models with large parameter size, resulting in both memory and computational cost complexities. In this work, we investigate the selection of representations…Apple Machine Learning Research

Co-ML: Collaborative Machine Learning Model Building for Developing Dataset Design Practices

Machine learning (ML) models are fundamentally shaped by data, and building inclusive ML systems requires significant considerations around how to design representative datasets. Yet, few novice-oriented ML modeling tools are designed to foster hands-on learning of dataset design practices, including how to design for data diversity and inspect for data quality.
To this end, we outline a set of four data design practices (DDPs) for designing inclusive ML models and share how we designed a tablet-based application called Co-ML to foster the learning of DDPs through a collbaborative ML model…Apple Machine Learning Research

User-level Differentially Private Stochastic Convex Optimization: Efficient Algorithms with Optimal Rates

We study differentially private stochastic convex optimization (DP-SCO) under user-level privacy where each user may hold multiple data items. Existing work for user-level DP-SCO either requires super-polynomial runtime or requires number of users that grows polynomially with the dimensionality of the problem. We develop new algorithms for user-level DP-SCO that obtain optimal rates, run in polynomial time, and require a number of users that grow logarithmically in the dimension. Moreover, our algorithms are the first to obtain optimal rates for non-smooth functions in polynomial time. These…Apple Machine Learning Research

Large-scale Training of Foundation Models for Wearable Biosignals

Tracking biosignals is crucial for monitoring wellness and preempting the development of severe medical conditions. Today, wearable devices can conveniently record various biosignals, creating the opportunity to monitor health status without disruption to one’s daily routine. Despite the widespread use of wearable devices and existing digital biomarkers, the absence of curated data with annotated medical labels hinders the development of new biomarkers to measure common health conditions. In fact, medical datasets are usually small in comparison to other domains, which is an obstacle for…Apple Machine Learning Research

Hybrid Model Learning for Cardiovascular Biomarkers Inference

This paper was accepted at the workshop Deep Generative Models for Health at NeurIPS 2023.
Cardiovascular diseases (CVDs) are a major global health concern, making the longitudinal monitoring of cardiovascular biomarkers vital for early diagnosis and intervention. A core challenge is the inference of cardiac pulse parameters from pulse waves, especially when acquired from wearable sensors at peripheral body locations. Traditional machine learning (ML) approaches face hurdles in this context due to the scarcity of labeled data, primarily sourced from clinical settings. Simultaneously, physical…Apple Machine Learning Research

One Wide Feedforward is All You Need

This paper was accepted at WMT conference at EMNLP.
The Transformer architecture has two main non-embedding components: Attention and the Feed Forward Network (FFN). Attention captures interdependencies between words regardless of their position, while the FFN non-linearly transforms each input token independently. In this work, we explore the role of FFN and find that despite, and find that despite taking up a significant fraction of the model’s parameters, it is highly redundant. Concretely, we are able to substantially reduce the number of parameters with only a modest drop in accuracy by…Apple Machine Learning Research

Bin Prediction for Better Conformal Prediction

This paper was accepted at the workshop on Regulatable ML at NeurIPS 2023.
Conformal Prediction (CP) is a method of estimating risk or uncertainty when using Machine Learning to help abide by common Risk Management regulations often seen in fields like healthcare and finance. CP for regression can be challenging, especially when the output distribution is heteroscedastic, multimodal, or skewed. Some of the issues can be addressed by estimating a distribution over the output, but in reality, such approaches can be sensitive to estimation error and yield unstable intervals. Here, we circumvent…Apple Machine Learning Research