shahab kamali
Shahab Kamali is the Technical Lead of Image-Content-Annotation (ICA) in Google Research. ICA is responsible for delivering image classification and detection models for major Google products such as Image Search, Photos, Google Cloud, Lens, and Maps . Shahab holds a PhD in Computer Science from University of Waterloo.
Authored Publications
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The Open Images Dataset V4: Unified image classification, object detection, and visual relationship detection at scale
Mohamad Hassan Mohamad Rom
Neil Alldrin
Ivan Krasin
Matteo Malloci
Alexander Kolesnikov
Vittorio Ferrari
IJCV (2020) (to appear)
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We present Open Images V4, a dataset of 9.2M images with unified annotations for image classification, object detection and visual relationship detection. The images have a Creative Commons Attribution license that allows to share and adapt the material, and they have been collected from Flickr without a predefined list of class names or tags, leading to natural class statistics and avoiding an initial design bias. Open Images V4 offers large scale across several dimensions: 30.1M image-level labels for 19.8k concepts, 15.4M bounding boxes for 600 object classes, and 375k visual relationship annotations involving 57 classes. For object detection in particular, we provide 15x more bounding boxes than the next largest datasets (15.4M boxes on 1.9M images). The images often show complex scenes with several objects (8 annotated objects per image on average). We annotated visual relationships between them, which support visual relationship detection, an emerging task that requires structured reasoning. We provide in-depth comprehensive statistics about the dataset, we validate the quality of the annotations, we study how the performance of several modern models evolves with increasing amounts of training data, and we demonstrate two applications made possible by having unified annotations of multiple types coexisting in the same images. We hope that the scale, quality, and variety of Open Images V4 will foster further research and innovation even beyond the areas of image classification, object detection, and visual relationship detection.
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Randomized Experimental Design via Geographic Clustering
David Rolnick
Amir Najmi
Proceedings of the 25th ACM SIGKDD International Conference on Knowledge Discovery & Data Mining (2019)
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Web-based services often run randomized experiments to improve their products. A popular way to run these experiments is to use geographical regions as units of experimentation, since this does not require tracking of individual users or browser cookies. Since users may issue queries from multiple geographical locations, georegions cannot be considered independent and interference may be present in the experiment. In this paper, we study this problem, and first present GeoCUTS, a novel algorithm that forms geographical clusters to minimize interference while preserving balance in cluster size. We use a random sample of anonymized traffic from Google Search to form a graph representing user movements, then construct a geographically coherent clustering of the graph. Our main technical contribution is a statistical framework to measure the effectiveness of clusterings. Furthermore, we perform empirical evaluations showing that the performance of GeoCUTS is comparable to hand-crafted geo-regions with respect to both novel and existing metrics.
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