Trends in Recommendations Systems – A Netflix Perspective

Thursday April 7th 2022 | 05.30 pm (CET) | via Zoom

Anuj Shah, Ph. D. | Senior Machine Learning Research Practitioner at Netflix


Recommendation systems today are widely used across many applications such as in multimedia content platforms, social networks, and ecommerce, to provide suggestions to users that are most likely to fulfill their needs, thereby improving the user experience. Academic research, to date, largely focuses on the performance of recommendation models in terms of ranking quality or accuracy measures, which often don’t directly translate into improvements in the real-world. In this talk, we present some of the most interesting challenges that we face in the personalization efforts at Netflix. The goal of this talk is to sunshine challenging research problems in industrial recommendation systems and start a conversation about exciting areas of future research.


Anuj Shah is a Senior Machine Learning Research Practitioner at Netflix. For the past 10+ years, he’s been working on an applied research team focused on developing the next generation of algorithms used to generate the Netflix homepage through machine learning, ranking, recommendation, and large-scale software engineering. He is extremely passionate about algorithms and technologies that help improve the Netflix customer experience with highly personalized consumer-facing products like the Continue Watching row, the Top 10 rows amongst many others. Prior to Netflix, he worked on machine learning in the Computational Sciences Division at the Pacific Northwest National Laboratory focusing on technologies at the intersection of proteomics, bioinformatics and Computer Science for 8 years. He has a Ph.D. from the Computer Science department at Washington State University and a Masters in C.S. from Virginia Tech.

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Introduction to 5G from radio perspective

Ms. Thura Hatim Al-Juboori | Ericsson Poland | Friday December 3, 2021 | 10:00 (CET, 09:00 UTC) |

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5G is the fifth generation of cellular networks. Up to 100 times faster than 4G, 5G is creating never-before-seen opportunities for people and businesses. Faster connectivity speeds, ultra-low latency and greater bandwidth is advancing societies, transforming industries and dramatically enhancing day-to-day experiences. Services that we used to see as futuristic, such as e-health, connected vehicles and traffic systems and advanced mobile cloud gaming have arrived. With 5G technology, we can help create a smarter, safer and more sustainable future.


* Network performance and evolution lead for all Europe and Latin America, Ericsson Company (Poland office)

* Professional consultant for network performance and 5G evolution lead with more than 15 years of experience in different Telco topics

* Responsibilities covering all Europe and Latin America:

Spectrum & Regulatory Advisory (spectrum and bandwidth acquisition advisory to operators, also spectrum interference topics)

NSA to SA Evolutions (5G spectrum architecture and deployment strategy

5G Evolution Proof Points (NSA/SA coverage extension NR mid band link budget, ESS spectrum sharing system simulator and SA strategy)  

Performance Benchmarking (OOKLA speed test and crowdsourced data analytics)

Network Performance Assessment (app coverage, VoLTE, recommended actions)

LTE/NR Product Segmentation (capacity improvement with NR introduction, DC /NR CA coverage extension gain)

LTE Capacity Expansion & Planning (LTE densification, transport capacity, NR introduction new use cases eMBB, FWA)

MBB Coverage & Device Analysis (smart network investment, improve coverage and CA strategy based on UE cap)

NR TDD Build with Precision (360 analysis based on site build, EMF, capacity, app coverage and TCO)

Site Evolution (network inventory & dimensioning)

Hot Topics (Cloud RAN, Open RAN, private network, and NW sharing)

Planning Network Evolutions with 5G Predictions Future 3 Years


   – TOP 15 woman in 5G (perspektywy woman in tech Dec. 2020)

   – Speaker and Mentor for ‚IT FOR SHE‘ Woman Tech Camp 2021

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Applied Data Science – Use Cases and Challenges in the Semiconductor Industry

Dr. Anja Zernig | KAI Kompetenzzentrum Automobil- und Industrieelektronik GmbH Villach |
Friday, November 26, 2021 | 10:00 (CET, 09:00 UTC) | Online:

Abstract: AI has infected the world. Today, there is a huge hype around Data Science activities all over the world, where one of the biggest challenges for the industry is to deliver financial value quickly but also sustainably. In her talk, she will show some examples on latest Use Cases in the area of Data Science within the semiconductor industry, including technical approaches and practical challenges. Further, she will give some personal insights on important enabling factors that make a Data Science project successful.

Bio: Anja Zernig coordinates Data Science projects at KAI Kompetenzzentrum Automobil- und Industrieelektronik GmbH in Villach, which is a 100% subsidiary of Infineon Technologies Austria AG. Dr. Zernig studied Technical Mathematics at the University of Klagenfurt and received her PhD in 2016. Afterwards, she has been applied as a researcher at KAI, focusing on topics like outlier and anomaly detection, pattern recognition, applied statistical methods and Machine Learning techniques. Since 2019 she is coordinating a team of Data Scientists, involved in various national and international funding projects and acts as a link between the industry and academic collaboration partners. She is supervising researchers and students, dealing with innovative data-analytical concepts within the semiconductor production, testing and optimization and publishes latest scientific insights in different conference and Journal papers. Beside this, Dr. Zernig participates in and supports local Data Science activities, e.g. she is part of the organizing team of the Women in Data Science Villach. In recent times, she is focusing on deployment strategies to guarantee sustainable Machine Learning lifecycles.

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RL-Cache: Learning-Based Cache Admission for Content Delivery

Sergey Gorinsky | IMDEA Networks Institute, Madrid |
Friday, November 12, 2021 | 14:00 (CET, 13:00 UTC) | S.0.05

Content delivery networks (CDNs) distribute much of the Internet content by caching and serving the objects requested by users. A major goal of a CDN is to maximize the hit rates of its caches, thereby enabling faster content downloads to the users. Content caching involves two components: an admission algorithm to decide whether to cache an object and an eviction algorithm to decide which object to evict from the cache when it is full. In this paper, we focus on cache admission and propose an algorithm called RL-Cache that uses model-free reinforcement learning (RL) to decide whether or not to admit a requested object into the CDN’s cache. Unlike prior approaches that use a small set of criteria for decision making, RL-Cache weights a large set of features that include the object size, recency, and frequency of access. We develop a publicly available implementation of RL-Cache and perform an evaluation using production traces for the image, video, and web traffic classes from Akamai’s CDN. The evaluation shows that RL-Cache improves the hit rate in comparison with the state of the art and imposes only a modest resource overhead on the CDN servers. Further, RL-Cache is robust enough that it can be trained in one location and executed on request traces of the same or different traffic classes in other locations of the same geographic region.

Sergey Gorinsky is a tenured Research Associate Professor at IMDEA Networks Institute in Madrid, Spain. He joined the institute in 2009 and leads the NetEcon (Network Economics) research group there. Dr. Gorinsky received his Ph.D. and M.S. degrees from the University of Texas at Austin, USA in 2003 and 1999 respectively and Engineer degree from Moscow Institute of Electronic Technology, Zelenograd, Russia in 1994. From 2003 to 2009, he served on the tenure-track faculty at Washington University in St. Louis, USA. In 2010-2014, Dr. Gorinsky was a Ramón y Cajal Fellow funded by the Spanish Government. Sergey Gorinsky graduated four Ph.D. students. The areas of his primary research interests are computer networking, distributed systems, and network economics. His work appeared at top conferences and journals such as SIGCOMM, CoNEXT, INFOCOM, Transactions on Networking, and Journal on Selected Areas in Communications. He served as a TPC chair of ICNP 2017 and other conferences, as well as a TPC member for a much broader conference population. Sergey Gorinsky contributed to conference organization in many roles, such as a general chair of SIGCOMM 2018 and ICNP 2020. He also served as an evaluator of research proposals and projects for the European Research Council (ERC StG), European Commission (Horizon 2020, FP7), COST Association, and numerous other funding agencies.

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Standardising the compressed representation of neural networks

Werner Bailer | Joanneum Research, Graz | Friday, June 25, 2021 | 10:00 (CET, 08:00 UTC) | online


Artificial neural networks have been adopted for a broad range of tasks in multimedia analysis and processing, such as visual and acoustic classification, extraction of multimedia descriptors or image and video coding. The trained neural networks for these applications contain a large number of parameters (weights), resulting in a considerable size. Thus, transferring them to a number of clients using them in applications (e.g., mobile phones, smart cameras) benefits from a compressed representation of neural networks.

MPEG Neural Network Coding and Representation is the first international standard for efficient compression of neural networks (NNs). The standard is designed as a toolbox of compression methods, which can be used to create coding pipelines. It can be either used as an independent coding framework (with its own bitstream format) or together with external neural network formats and frameworks. For providing the highest degree of flexibility, the network compression methods operate per parameter tensor in order to always ensure proper decoding, even if no structure information is provided. The standard contains compression-efficient quantization and an arithmetic coding scheme (DeepCABAC) as core encoding and decoding technologies, as well as neural network parameter pre-processing methods like sparsification, pruning, low-rank decomposition, unification, local scaling and batch norm folding. NNR achieves a compression efficiency of more than 97% for transparent coding cases, i.e. without degrading classification quality, such as top-1 or top-5 accuracies.

This talk presents an overview of the context, technical features and characteristics of NN coding standard, and discusses ongoing topics such as incremental neural network representation.


Werner Bailer is a Key Researcher at DIGITAL – Institute for Information and Communication Technologies at JOANNEUM RESEARCH in Graz, Austria. He received a degree in Media Technology and Design in 2002 for his diploma thesis on motion estimation and segmentation for film/video standards conversion. His research interests include audiovisual content analysis, multimedia retrieval and machine learning. He regularly contributes to standardization, among others in MPEG, where he co-chairs the ad-hoc group on neural network compression.

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Edge computing in 5G networks

Benedek Kovács PhD | Senior Specialist, Ericsson R&D at Hungary | Friday, May 28, 2021 |

10:30 (CET, 08:30 UTC) |

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Abstract: We overview the edge computing status from a telecommunication networks perspective, give a definition, introduce an example. We discuss the different driving forces in the telecommunication and cloud industry and go thorugh the different solution proposals. We cover the networking, cloud and management aspects and show the different options using the example.

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Cloud, Fog, or Edge: Where and When to Compute?

Dragi Kimovski | Alpen-Adria-Universität Klagenfurt | Friday, December 18, 2020 | 11:00 (CET, 10:00 UTC) | online

Abstract: The computing continuum extends the high-performance cloud data centers with energy-efficient and low-latency devices close to the data sources located at the edge of the network. However, the heterogeneity of the computing continuum raises multiple challenges related to application and data management. These include (i) how to efficiently provision compute and storage resources across multiple control domains across the computing continuum, (ii) how to decompose and schedule an application, and (iii) where to store an application source and the related data. To support these decisions, we explore in this thesis, novel approaches for (i) resource characterization and provisioning with detailed performance, mobility, and carbon footprint analysis, (ii) application and data decomposition with increased reliability, and (iii) optimization of application storage repositories. We validate our approaches based on a selection of use case applications with complementary resource requirements across the computing continuum over a real-life evaluation testbed.

Bio: Dragi Kimovski is a postdoctoral researcher with “Zielvereinbarung” at the Institute of Information Technology (ITEC), University of Klagenfurt. He earned his doctoral degree in 2013 from the Technical University of Sofia. He was an assistant professor at the University for Information Science and Technology in Ohrid, and a senior researcher and lecturer at the University of Innsbruck. During his career, he conducted multiple research stays at the University of Michigan, University of Bologna, and University of Granada. He was a work package leader and scientific coordinator in two Horizon 2020 projects (ENTICE and ASPIDE), and coordinated the OeAD AtomicFog project. He co-authored more than 40 articles in international conferences and journals. His research interests include parallel and distributed computing, fog and edge computing, multi-objective optimization, and distributed processing for bioengineering applications.

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Navigation in 360-Degree Video Content: Challenges, Solutions and Opportunities

Klara Nahrstedt | University of Illinois | Thursday, December 17, 2020 | 15:00 (CET, 14:00 UTC) | online

Abstract: With the emergence of  360-degree cameras, VR/AR display devices, ambisonics auditory devices, more diverse 360-degree multi-modal content has become available and with it the challenging demands for the capability of navigating within the 360-degree multi-modal content to enhance users’ multi-modal experience.  In this talk, we will discuss the challenges of navigating through the 360-degree multi-modal content in a HMD-Cloud-based distributed environment, and discuss the concept of the navigation graph to organize the 360-video content for successful delivery and viewing. We will dive into more details of the navigation graph’ concept as one possible direction of potential solutions to represent views-objects-tiles navigation. We will show how navigation graphs are serving as models for viewing behaviors in the temporal and spatial domains to perform a better rate adaptation of tiled media associated with view and object predictions. The experimental results are encouraging and support the claim that the navigation graph modeling provides a strong representation of navigation and viewing patterns of users, and its usage enhances the streaming and viewing quality in 360-degree video applications. We conclude the talk with research opportunities that this area is offering.

Joint work with UIUC collaborators: Dr. Jounsup Park, Mingyuan Wu, Eric Lee, Bo Chen, and UMass collaborators: Ariel Rosenthal, Yash Shah, John Murray, Kevin Spiteri, Dr. Michael Zink, Dr. Ramesh Sitaraman.

Bio: Klara Nahrstedt is the Ralph and Catherine Fisher Professor in the Computer Science Department, and Director of Coordinated Science Laboratory in the College of Engineering at the University of Illinois at Urbana-Champaign. Her research interests are directed toward Internet-of-Things systems, tele-immersive systems, end-to-end Quality of Service (QoS) and resource management in large scale distributed systems and networks, and real-time security and privacy in cyber-physical systems such as power grid. She is the co-author of multimedia books `Multimedia: Computing, Communications and Applications‘ published by Prentice Hall, and ‘Multimedia Systems’ published by Springer Verlag.

She is the recipient of the IEEE Communication Society Leonard Abraham Award for Research Achievements, University Scholar, Humboldt Research Award, IEEE Computer Society Technical Achievement Award, ACM SIGMM Technical Achievement Award, TU Darmstadt Piloty Prize, the Grainger College of Engineering Drucker Award, and the former chair of the ACM Special Interest Group in Multimedia. She was the general co-chair and TPC co-chair of many international conferences including ACM Multimedia, IEEE Percom, IEEE IOTDI and others. Klara Nahrstedt received her Diploma in Mathematics from Humboldt University, Berlin, Germany in 1985. In 1995 she received her PhD from the University of Pennsylvania in the Department of Computer and Information Science. She is ACM Fellow, IEEE Fellow, AAAS Fellow, and Member of the German National Academy of Sciences (Leopoldina Society).

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In the region – for the region? The multiple roles of universities for their (rural) siting region

DI Dr. Verena Radinger-Peer

Institute for Sustainable Economic Development, University of Natural Resources and Life Sciences, BOKU Vienna

Friday, October 23rd, 2020 | 9:30  HS10 | via classroom:

Abstract: Locating universities in regions where they should spur regional development has been recognized as an important regional political “instrument“ since the middle of the twentieth century. The expected impacts on regional development range from economic, political, demographic, infrastructural, cultural, educational, to social. Thereby various studies confirm that a) the university-region setting is unique and context-specific and b) universities will not spur regional development autonomously or inevitably.

The presentation will show the potentials but also challenges of universities being located in rural regions. This refers to balancing acts between internationality and regional focus, economic performance and societal engagement, curriculum development and demands of the regional/national labor market etc. Particular attention is paid to income students (origin, attraction) as well as the migration of graduates. Hereby the presentations builds on insights from former and ongoing projects with national and international case studies (Germany, The Netherlands). The presentation will conclude with insights on strategies how universities in rural siting regions dealt with this multiple challenges as well as how the regional environment influenced the role the universities resumed.

CV: Verena Radinger-Peer (Dr. nat. techn., Dipl.-Ing.) is trained as spatial and environmental planner and gained her PhD in regional development and economics at the University of Natural Resources and Life Sciences Vienna (BOKU). She was a visiting scholar at the Fraunhofer Institute ISI in Karlsruhe (Germany) as well as at the CHEPS (Center for Higher Education Policy Studies) at the University of Twente (The Netherlands).

Currently she is a FWF Hertha Firnberg Grant holder and investigates the interaction between universities and their surrounding region, with a special focus on knowledge transfer, student intake and mobility, labour market issues as well as regional engagement activities of universities.

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Content-gnostic Bitrate Ladder Prediction for Adaptive Video Streaming [Slides][Video]

Angeliki Katsenou | University of Bristol | September 29, 2020 | 10:00 (CET, 08:00 UTC)

Abstract: Cisco reported in the past reports that the video data share was expected to reach 80% by the year 2023. However, due to the pandemic and recently imposed a remote work lifestyle, this figure is expected to increase even more. Except for the on-demand and conferencing services, the number of users that are generating, storing, and sharing their content usually through either social media platforms or video-sharing platforms is increasing. Meanwhile from the video coding perspective, as video technologies evolve towards improved compression performance, their complexity inversely increases.

A challenge that many video service providers face is the heterogeneity of networks and display devices for streaming, as well as dealing with a wide variety of content with different encoding performance. In the past, a fixed bit rate ladder solution based on a „fitting all“ approach has been employed. However, such a content-tailored solution is highly demanding; the computational and financial cost of constructing the convex hull per video by encoding at all resolutions and quantization levels is huge. In this talk, we present a content-agnostic approach that exploits machine learning to predict the bit rate ladder with only a small number of encodes required.

Bio: Angeliki Katsenou is a Leverhulme Early Career Fellow and is with the Visual Information Lab at the University of Bristol since 2015. She obtained her Ph.D. degree from the Department of Computer Science and Engineering, University of Ioannina, Greece (2014). She received her Diploma in Electrical and Computer Engineering and an M.Sc. degree in Signal and Image Processing from the University of Patras, Greece. She has experience in several FP7 EC-funded and EPSRC projects, such as MSCA-ITN PROVISION and EPSRC Platform Grant EP/M000885/1. Her research interests include perceptual video analysis, video compression, image/video quality, and resource allocation for video communication systems. She has also been involved with conference organization activities and is currently one of the Technical Program Co-Chairs for Picture Coding Symposium (PCS) 2021, Bristol, UK.

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