  Enhancing semantic grounding abilities in Vision-Language Models (VLMs) often
involves collecting domain-specific training data, refining the network
architectures, or modifying the training recipes. In this work, we venture into
an orthogonal direction and explore whether VLMs can improve their semantic
grounding by "receiving" feedback, without requiring in-domain data,
fine-tuning, or modifications to the network architectures. We systematically
analyze this hypothesis using a feedback mechanism composed of a binary signal.
We find that if prompted appropriately, VLMs can utilize feedback both in a
single step and iteratively, showcasing the potential of feedback as an
alternative technique to improve grounding in internet-scale VLMs. Furthermore,
VLMs, like LLMs, struggle to self-correct errors out-of-the-box. However, we
find that this issue can be mitigated via a binary verification mechanism.
Finally, we explore the potential and limitations of amalgamating these
findings and applying them iteratively to automatically enhance VLMs' grounding
performance, showing grounding accuracy consistently improves using automated
feedback across all models in all settings investigated. Overall, our iterative
framework improves semantic grounding in VLMs by more than 15 accuracy points
under noise-free feedback and up to 5 accuracy points under a simple automated
binary verification mechanism. The project website is hosted at
https://andrewliao11.github.io/vlms_feedback
