Details Colloquium Spring 2016

03.03.2016 - The Requirements Problem in Software Engineering

Speaker: Prof. John Mylopoulos, Ph.D.

Host: Prof. Dr. Martin Glinz

Abstract

The requirements problem is the problem of deriving a specification consisting of functions and quality constraints that along with a set of domain assumptions satisfy a given set of requirements. We present several formulations of the requirements problem to account for changing requirements, adaptive software design and the next release problem. In each case, we discuss the tractability of algorithms that search spaces of alternatives to find Pareto-optimal solutions to the problem. This is joint work with many colleagues and students, including Roberto Sebastiani, Paolo Giorgini, Fatma Aydemir, Chi Mai Nguyen (UniTN), Neil Ernst (CMU), Alex Borgida (Rutgers) and Ivan Jureta (Namur).

Bio

John Mylopoulos holds a professor emeritus position at the Universities of Toronto and Trento. He earned a PhD degree from Princeton University in 1970 and joined the faculty of the Department of Computer Science at the University of Toronto the same year. His research interests include conceptual modelling, requirements engineering, data semantics and knowledge management. Mylopoulos is a fellow of the Association for the Advancement of Artificial Intelligence (AAAI) and the Royal Society of Canada (Academy of Applied Sciences). He has served as programme/general chair of international conferences in Artificial Intelligence, Databases and Software Engineering, including IJCAI (1991), Requirements Engineering (1997, 2011), and VLDB (2004). Mylopoulos is currently leading a project titled "Lucretius: Foundations for Software Evolution”, funded by an advanced grant from the European Research Council.

17.03.2016 - Reading News with Maps by Exploiting Spatial Synonyms

Speaker: Prof. Hanan Samet, Ph.D.

Hosts: Prof. Dr. Renato Pajarola, Prof. Dr. Michael Böhlen

Abstract

NewsStand is an example application of a general framework to enable people to search for information using a map query interface, where the information results from monitoring the output of over 10,000 RSS news sources and is available for retrieval within minutes of publication. The advantage of doing so is that a map, coupled with an ability to vary the zoom level at which it is viewed, provides an inherent granularity to the search process that facilitates an approximate search thereby permitting the use of spatial synonyms instead of being limited to an exact match of a query string. This is predicated on the use of a textual specification of locations rather than a geometric one, which means that one must deal with the potential for ambiguity. The issues that arise in the design of a system like NewsStand, including the identification of words that correspond to geographic locations, are discussed, and examples are provided of its utility. More details can be found in the video at http://vimeo.com/106352925 which accompanies the "cover article'' of the October 2014 issue of the Communications of the ACM about NewsStand at http://tinyurl.com/newsstand-cacm or a cached version at at http://www.cs.umd.edu/~hjs/pubs/cacm-newsstand.pdf

Bio

Prof. Hanan Samet, Ph.D. is a Distinguished University Professor of Computer Science at the University of Maryland, College Park. He received the B.S. degree in engineering from UCLA, and the M.S. Degree in operations research and the M.S. and Ph.D. degrees in computer science from Stanford University. His doctoral dissertation dealt with proving the correctness of translations of LISP programs which was the first work in translation validation and the related concept of proof-carrying code. He is the author of the recent book "Foundations of Multidimensional and Metric Data Structures" published by Morgan-Kaufmann, an imprint of Elsevier, in 2006, an award winner in the 2006 best book in Computer and Information Science competition of the Professional and Scholarly Publishers (PSP) Group of the American Publishers Association (AAP), and of the first two books on spatial data structures "Design and Analysis of Spatial Data Structures", and "Applications of Spatial Data Structures: Computer Graphics, Image Processing, and GIS", both published by Addison-Wesley in 1990. He is the Founding Editor-In-Chief of the ACM Transactions on Spatial Algorithms and Systems (TSAS), founding chair of ACM SIGSPATIAL, and a Fellow of ACM, IEEE, AAAS, IAPR (International Association of Pattern Recognition), and UCGIS (University Consortium for Geographic Science). He is a recipient of a Science Foundation of Ireland (SFI) Walton Visitor Award at the Centre for Geocomputation at the National University of Ireland at Maynooth (NUIM), 2009 UCGIS Research Award, 2011 ACM Paris Kanellakis Theory and Practice Award, and 2014 IEEE Computer Society Wallace McDowell Award. He has had a number of best paper awards including at the 2008 SIGMOD and SIGSPATIAL conferences. He was elected to the ACM Council as the Capitol Region Representative for the term 1989-1991, and is an ACM Distinguished Speaker.

31.03.2016 - Experts versus the Crowd: A Comparison of Selection Mechanisms in Crowdsourcing Contests

Speaker: Prof. De Liu, Ph.D.

Host: Prof. Dr. Daning Hu

Abstract

Selection mechanism is an important but underexplored dimension of contest designs. We compare two popular selection mechanisms, expert rating and crowd voting, in crowdsourcing contests for creative works. Using a unique panel that has expert rating and crowd voting in the same contest, we systematically compare the two selection mechanisms in terms of winner determination and their effects on participation. We find that expert rating and crowd voting are quite different. Crowd voting strongly favors contestants who submit early and have high levels of social engagement, but expert rating does not. Past performance under one selection mechanism predicts future success under the same selection mechanism, but not the other. Expert rating and crowd voting also differ in their effects on participation: crowd voting is relatively more attractive when contestants have little experience and when they have performed well in crowd-voted prizes, and the overall participation increases with the ratio of crowd-voted prizes.

Bio

Dr. De Liu is an associate professor of Information and Decisions Sciences at the University of Minnesota. He earned his Ph.D. in Management Science and Information Systems at the University of Texas at Austin. His research interests include auction and market mechanisms, knowledge and social networks, and gamification.

07.04.2016 - Optimizing Software Development Processes

Speaker: Brendan Murphy

Host: Prof. Dr. Thomas Fritz

Abstract

It would appear that developing software programs or services is one of the easiest things in the world to do. The theorist would have us believe that all practitioners need to do is to write the code in specific software language (e.g. functional language) and follow specific processes (e.g. agile) and ideally deploy as a continuously evolving service and you will reach perfection. If you run into problems then that is because your engineers are not good enough and/or you are not following the process correctly. The reality is very different, especially when developing software at scale. This talk will describe why there are no universal development processes that can be applied across all software product and service. While practitioners are well aware of this reality, there is little assistance, based on empirical evidence, to help them either choose a suitable development process for their product or service, or in optimizing the solution they have already chosen. Over the last few years I and other researchers have being looking at how to assist developers in optimizing their process, based on the attributes of the product or services they are developing. In this talk I will describe the current state of our research in this space.

Bio

Brendan Murphy is a Principal Researcher at the Microsoft Research Centre in Cambridge UK. Brendan works in the Empirical Software Engineering and Measurement (ESE) group at Microsoft focusing on software reliability, dependability, quality and process issues. Over the last year Brendan has been researching software development practices within Microsoft. Prior to his current position at Microsoft, Brendan was at Compaq Corporation (previously Digital), Ayr Scotland till August 1999, where he ran the DPP program which collected and analysed dependability data from customer sites. Prior to working in Scotland, Brendan worked for Digital in Galway Ireland, UNISYS (Scotland and US) and ICL (West Gorton, Manchester). Brendan graduated from Newcastle University. In his free time you can find him playing golf in and around Cambridge.

14.04.2016 - Measuring the Wireless World

Speaker: Prof. Dr. Jukka Manner

Host: Prof. Dr. Burkhard Stiller

Abstract

People around the world are moving strongly towards cellular access to Internet services. Yet, as we all know, radio access is much more unreliable than wireline, and the quality of experience also varies. What is the typical access performance people experience around the world ? How has that changed over the years ? What are issues affecting the performance ? How do the quality of the network or the device performance manifest in measuring mobile performance ? The talk will discuss issues related to measuring and analyzing mobile connectivity using the Netradar mobile measurement service developed at Aalto University since 2010. The presentation will include a lot of analysis about various topics, from comparing continents and countries, to digging into the performance of individual operators and even mobile device models.

Bio

Prof. Dr. Jukka Manner (born 1972) received his MSc. (1999) and PhD. (2004) degrees in computer science from the University of Helsinki. He is a full professor (tenured) of networking technology at Aalto University, Department of Communications and Networking (Comnet). His research and teaching focuses on networking, software and distributed systems, with a strong focus on wireless and mobile networks, transport protocols, energy efficient ICT and cyber security. He was the Academic Coordinator for the Finnish Future Internet research programme 2008-2012. He is an active peer reviewer and member of various TPCs. He was the local co-chair of Sigcomm 2012 in Helsinki. He has contributed to standardization of Internet technologies in the IETF since 1999, and was the co-chair of the NSIS working group. He has been principal investigator and project manager for over 15 national and international research projects. He has authored over 100 publications, including eleven IETF RFCs. He is a member of the IEEE. In 2014 he received the Cross of Merit, Signals, and in 2015 the Medal for Military Merits for contributions in national defence and C4.

12.05.2016 - Quizz: Targeted Crowdsourcing with a Billion (Potential) Users

Speaker: Prof. Panos Ipeirotis, Ph.D.

Host: Prof. Dr. Abraham Bernstein

Abstract

We describe Quizz, a gamified crowdsourcing system that simultaneously assesses the knowledge of users and acquires new knowledge from them. Quizz operates by asking users to complete short quizzes on specific topics; as a user answers the quiz questions, Quizz estimates the user’s competence. To acquire new knowledge, Quizz also incorporates questions for which we do not have a known answer; the answers given by competent users provide useful signals for selecting the correct answers for these questions. Quizz actively tries to identify knowledgeable users on the Internet by running advertising campaigns, effectively leveraging “for free” the targeting capabilities of existing, publicly available, ad placement services. Quizz quantifies the contributions of the users using information theory and sends feedback to the advertising system about each user. The feedback allows the ad targeting mechanism to further optimize ad placement. Our experiments, which involve over ten thousand users, confirm that we can crowdsource knowledge curation for niche and specialized topics, as the advertising network can automatically identify users with the desired expertise and interest in the given topic. We present controlled experiments that examine the effect of various incentive mechanisms, highlighting the need for having short-term rewards as goals, which incentivize the users to contribute. Finally, our cost-quality analysis indicates that the cost of our approach is below that of hiring workers through paid-crowdsourcing platforms, while offering the additional advantage of giving access to billions of potential users all over the planet, and being able to reach users with specialized expertise that is not typically available through existing labor marketplaces.

Bio

Prof. Panos Ipeirotis, Ph.D., is an Associate Professor and George A. Kellner Faculty Fellow at the Department of Information, Operations, and Management Sciences at Leonard N. Stern School of Business of New York University. He received his Ph.D. degree in Computer Science from Columbia University in 2004. He has received nine “Best Paper” awards and nominations, a CAREER award from the National Science Foundation, and is the recipient of the 2015 Lagrange Prize in Complex Systems, for his contributions in the field of social media, user-generated content and crowdsourcing.

26.05.2016 - Reflections on 15+ Years Exploring Personalized Users Interfaces

Speaker: Prof. Joanna McGrenere, Ph.D.

Host: Prof. Dr. Thomas Fritz

Abstract

There is no such thing as an average user. Users bring their own individual needs, desires, and skills to their everyday use of interactive technologies. Yet many of today’s technologies, from desktop applications to mobile devices and apps, are still designed for some mythical average user. It seems intuitive that interfaces should be designed with adaptation in mind so that they would better accommodate individual differences among users. Yet, what seems intuitive is not necessarily straightforward. I will highlight examples of my group’s research in the area of personalized user interfaces, reaching briefly back to my own PhD work and moving through to recent day explorations. I will touch on various approaches to adaptation, what we’ve learned about the strengths and limitations of those approaches, and where promising future opportunities lie.

Bio

Prof. Joanna McGrenere, Ph.D. is with the Department of Computer Science at the University of British Columbia (UBC). She is currently spending a sabbatical year with the Ex-Situ lab at INRIA, France. Joanna received a PhD from the University of Toronto in 2002, an MSc from UBC in 1996, and a BSc from Western University in 1993, all in Computer Science. Her broad research area is Human Computer Interaction (HCI), with a specialization in interface personalization, universal usability, assistive technology, and computer supported cooperative work. She often serves on program committees for the top conferences in HCI, including serving as the Papers Co-Chair for CHI in 2015. She is a member of the editorial board for ACM Transactions on Computer-Human-Interaction (ToCHI) and ACM Transactions on Accessible Computing (TACCESS). Joanna won a Microsoft Research Software Engineering Innovation Foundation (SEIF) award in 2013, a Killam award for Excellence in Mentoring (2012), an Outstanding Young Computer Science Research Award from the Canadian Association of Computer Science (2011), was appointed as a Peter Wall Institute for Advanced Studies Early Career Scholar (2010), and was the first recipient of the Anita Borg Early Career Scholar Award (2004). Joanna was recently an Associate Head in CS at UBC (2013-15) and lead the new HCI@UBC initiative: an interdisciplinary meeting for scholars working in the area of Human-Computer Interaction at UBC (2013-15).