Title: Free-Form Gesture Authentication in the Wild
Abstract: Free-form gesture passwords have been introduced as an alternative mobile authentication method. Text passwords are not very suitable for mobile interaction, and methods such as PINs and grid patterns sacrifice security over usability. However, little is known about how free-form gestures perform in the wild. We present the first field study (N=91) of mobile authentication using free-form gestures, with text passwords as a baseline. Our study leveraged Experience Sampling Methodology to increase ecological validity while maintaining control of the experiment. We found that, with gesture passwords, participants generated new passwords and authenticated faster with comparable memorability while being more willing to retry. Our analysis of the gesture password dataset indicated biases in user-chosen distribution tending towards common shapes. Our findings provide useful insights towards understanding mobile device authentication and gesture-based authentication. This paper will be formally published in CHI’16, the ACM annual premier conference in HCI, held in San Jose, CA May 2016.
Biography: Yulong Yang is a fifth-year Ph.D. student in the Department of Electrical and Computer Engineering. His research advisor is Professor Janne Lindqvist. His interests are in usable security, mobile applications and human computer interaction. He has worked on publications that accepted to conferences including Mobisys, Ubicomp, LASER, etc. He received B.S. degree in Electrical Engineering from University of Electronic and Scientific Technology of China in 2011.
Title: Of Two Minds, Multiple Addresses, and One Ledger: Characterizing Opinions, Knowledge, and Perceptions of Bitcoin Across Users and Non-Users
Abstract: Digital currencies represent a new method for exchange – a payment method with no physical form, made real by the Internet. This new type of currency was created to ease online transactions and to provide greater convenience in making payments. However, a critical component of a monetary system is the people who use it. Acknowledging this, we present results of our interview study (N=20) with two groups of participants (users and non-users) about how they perceive the most popular digital currency, Bitcoin. Our results reveal: non-users mistakenly believe they are incapable of using Bitcoin, users are not well-versed in how the protocol functions, they have misconceptions about the privacy of transactions, and that Bitcoin satisfies properties of ideal payment systems as defined by our participants. Our results illustrate Bitcoin’s tradeoffs, its uses, and barriers to entry. The work has been featured in over 100 popular media and web sites so far, including Yahoo! Finance News, Morningstar, IBS Intelligence, NSF’s website, Benzinga, and Neowin. The paper will be formally published in CHI’16, the ACM annual premier conference in HCI, held in San Jose, CA May 2016.
Biography: Xianyi Gao is currently a PhD student in the Department of Electrical and Computer Engineering (ECE) at Rutgers University. He is a recipient of the NSF GRFP award. He received the Best Paper Nominee Award from UbiComp’14. He is currently working under supervision of Dr. Janne Lindqvist on areas related to Human-Computer Interaction. His research interests include security and privacy for cryptocurrencies, automobiles, and other mobile systems. He joined the ECE PhD program in Fall 2013. Before that, he obtained his undergraduate degree in electrical engineering from Rutgers University as well.