Reply to "build more diverse and representative datasets in the future"
Thank you for your clarifications. Indeed, our previous response focused more on past efforts. **Here we provide several ways our framework can be used to help build more diverse and representative datasets in the future:**
- When considering adding a new set of images (e.g., from another website) into a data collection, we can first treat new images as a separate dataset, use the transformation and classification framework to tell where and how much they differ from the existing image collections. This can help us decide whether to join them. If the goal is to enhance diversity of the dataset in a certain aspect (e.g., object types), we should only join them when they are sufficiently different.
- Our language-based analysis provides textual descriptions for any new dataset. This text description directly gives the data curators the intuition on the gist of the dataset, especially when compared with reference datasets. It can help curators refine text terms for image search and tag filtering, in search engines or other platforms.
- Our framework can identify bias and distribution imbalance in the image statistics (e.g., colors and object distribution). This can help guide adding/removing images with desired/undesired statistics for more balance.
- The result of a dataset classifier trained on the transformed datasets can serve as a measure of the image's "typicality" within the dataset. For example, images in dataset A that are misclassified as images in dataset B are considered "not typical" within A, for that transformation/attribute. If needed, images with less typical attributes can be then oversampled in collecting data and/or training to enhance representation.
**In addition to how to use the framework, we list a few direct lessons we learned from our analysis on YCD, that can also help build more diverse and representative datasets in the future:**
- Filtering by embedding similarity to images of a reference dataset could inherit bias of that dataset.
We observe that DataComp has the lowest number of unique objects per image (Fig 12). This potentially resulted from DataComp filtering for images with high embedding similarity to ImageNet training examples, most of which feature object-centric images [1].
To mitigate this, dataset curators should be mindful of the inherent biases in their reference datasets (e.g., ImageNet). Concretely, to enhance the object diversity within DataComp, one could consider using a reference dataset with a higher per-image object diversity (e.g., COCO) during filtering.
- The source website's image collection mechanism can introduce bias.
We also noted that YFCC is heavily skewed towards outdoor scenes and human interactions (Sec 4.2). This bias likely stems from its reliance on a single data source, Flickr, where user-generated content often focuses on personal photos, landscapes, and social interactions. Dataset curators should recognize that the collection methods (e.g., user uploads) of data sources (e.g., Flickr) can introduce biases into the resulting dataset (e.g., YFCC).
- Web-scraped images would naturally contain more digital graphics.
Since CC and DataComp are crawled from the Internet, they feature results from search engines [2, 3]. This prioritizes professionally created content like advertisements, infographics, and digital media. Curators should evaluate whether this composition aligns with their downstream goals.
Thank you for your quick reply/clarification. We will add a discussion on this to the paper and see it as an important improvement. We also hear your suggestion on moving experiments to the appendix for the space. Given that NeurIPS policy allows an additional page for accepted publications, we would be able to add the discussion while maintaining the current experiments. We are happy to address any further concerns.
References:\
[1] Barbu et al, ObjectNet: A large-scale bias-controlled dataset for pushing the limits of object recognition models\
[2] Changpinyo et al, Conceptual 12M: Pushing Web-Scale Image-Text Pre-Training To Recognize Long-Tail Visual Concepts\
[3] Gadre et al, DataComp: In search of the next generation of multimodal datasets