Introduction to Special Issue based on papers presented at the Workshop on Information Technology and Systems, 2017
The Centers for Medicare & Medicaid Services (CMS) launched its nursing home rating system in 2008, which has been widely used among patients, doctors and insurance companies. The system rates nursing homes based on a combination of CMSs inspection results and nursing homes self-reported measures. Prior research has shown that the rating system is subject to inflation in the self-reporting procedure, leading to biased overall ratings. Given the limited resources CMS has, it is important to optimize the inspection process and develop an effective audit process to detect and deter inflation. In this paper, we first examine if the domain that CMS currently inspects is the best choice in terms of reducing the percentage of nursing homes that can inflate and reducing the difficulty of detecting such inflators. We develop a novel graph-based approach and use publicly available data on nursing home ratings to show that CMSs current choice of inspection domain is not optimal if it intends to minimize the number of potential inflators, and CMS will be better off if it inspects the staffing domain instead. We also show that CMSs current choice of inspection domain is only optimal had there been an audit system in place to complement it. We then design an auditing system for CMS which will be coupled with its current inspection strategy. We analyze the performance of the audit system in terms of net audit budget and audit efficiency. To design the audit system, we consider nursing homes reactions to different audit policies, and conduct a detailed simulation study on the optimal audit parameter settings. Our result suggests that CMS should use a moderate audit policy in order to carefully balance the tradeoff between audit net budget and audit efficiency.
The QWERTY keyboard on mobile devices usually requires users? full visual attention and both hands, which are not always possible. We propose a thumb-stroke based keyboard, ThumbStroke, to support both sight-free and one-handed text entry. Selecting characters via ThumbStroke completely relies on the directions of thumb movements at any place on the screen of a mobile device. It does not require physical press of any specific keys, thus eliminating the need of visual attention and reducing errors due to tiny key size, fat thumb, limited thumb reachability, and visual occlusion. We empirically evaluated ThumbStroke through a 20-session longitudinal controlled lab experiment. ThumbStroke shows advantages in typing accuracy and user perceptions in comparison to the Escape and QWERTY keyboards for one-handed text entry, and results in faster typing speed than QWERTY in sight-free and one-handed text entry. This study provides novel research contributions to mobile HCI, advancing the design of soft keyboards for one-handed interaction with mobile devices and mobile accessibility.