3 research outputs found
On-Device Model Fine-Tuning with Label Correction in Recommender Systems
To meet the practical requirements of low latency, low cost, and good privacy
in online intelligent services, more and more deep learning models are
offloaded from the cloud to mobile devices. To further deal with cross-device
data heterogeneity, the offloaded models normally need to be fine-tuned with
each individual user's local samples before being put into real-time inference.
In this work, we focus on the fundamental click-through rate (CTR) prediction
task in recommender systems and study how to effectively and efficiently
perform on-device fine-tuning. We first identify the bottleneck issue that each
individual user's local CTR (i.e., the ratio of positive samples in the local
dataset for fine-tuning) tends to deviate from the global CTR (i.e., the ratio
of positive samples in all the users' mixed datasets on the cloud for training
out the initial model). We further demonstrate that such a CTR drift problem
makes on-device fine-tuning even harmful to item ranking. We thus propose a
novel label correction method, which requires each user only to change the
labels of the local samples ahead of on-device fine-tuning and can well align
the locally prior CTR with the global CTR. The offline evaluation results over
three datasets and five CTR prediction models as well as the online A/B testing
results in Mobile Taobao demonstrate the necessity of label correction in
on-device fine-tuning and also reveal the improvement over cloud-based learning
without fine-tuning