  Data-centric AI approach aims to enhance the model performance without
modifying the model and has been shown to impact model performance positively.
While recent attention has been given to data-centric AI based on synthetic
data, due to its potential for performance improvement, data-centric AI has
long been exclusively validated using real-world data and publicly available
benchmark datasets. In respect of this, data-centric AI still highly depends on
real-world data, and the verification of models using synthetic data has not
yet been thoroughly carried out. Given the challenges above, we ask the
question: Does data quality control (noise injection and balanced data), a
data-centric AI methodology acclaimed to have a positive impact, exhibit the
same positive impact in models trained solely with synthetic data? To address
this question, we conducted comparative analyses between models trained on
synthetic and real-world data based on grammatical error correction (GEC) task.
Our experimental results reveal that the data quality control method has a
positive impact on models trained with real-world data, as previously reported
in existing studies, while a negative impact is observed in models trained
solely on synthetic data.
