Learning to rank – producing a ranked list of items specific to a query and with respect to a set of supervisory items – is a problem of general interest. The setting we consider is one in which no analytic description of what constitutes a good ranking is available. Instead, we have a collection of representations and supervisory information consisting of a (target item, interesting items set) pair. We demonstrate analytically, in simulation, and in real data examples that learning to rank via combining representations using an integer linear program is effective when the supervision is as light as “these few items are similar to your item of interest.” While this nomination task is quite general, for specificity we present our methodology from the perspective of vertex nomination in graphs. The methodology described herein is model agnostic.

Datacenter systems and I/O devices now run at single-digit microsecond latencies, requiring ns-scale operating systems. Traditional kernel-based operating systems impose an unaffordable overhead, so recent kernel-bypass OSes [73] and libraries [23] eliminate the OS kernel from the I/O datapath. However, none of these systems offer a general-purpose datapath OS replacement that meet the needs of μs-scale systems.' [email protected] paper proposes Demikernel, a flexible datapath OS and architecture designed for heterogenous kernel-bypass devices and μs-scale datacenter systems. We build two prototype Demikernel OSes and show that minimal effort is needed to port existing μs-scale systems. Once ported, Demikernel lets applications run across heterogenous kernel-bypass devices with ns-scale overheads and no code changes.

Through an iterative design process using Wizard of Oz (WOz) prototypes, we designed a video calling application for people with Autism Spectrum Disorder. Our Video Calling for Autism prototype provided an Expressiveness Mirror that gave feedback to autistic people on how their facial expressions might be interpreted by their neurotypical conversation partners. This feedback was in the form of emojis representing six emotions and a bar indicating the amount of overall expressiveness demonstrated by the user. However, when we built a working prototype and conducted a user study with autistic participants, their negative feedback caused us to reconsider how our design process led to a prototype that they did not find useful. We reflect on the design challenges around developing AI technology for an autistic user population, how Wizard of Oz prototypes can be overly optimistic in representing AI-driven prototypes, how autistic research participants can respond differently to user experience prototypes of varying fidelity, and how designing for people with diverse abilities needs to include that population in the development process.