On the limits of the human motor control precision: the search for a device’s human resolution

Abstract. Input devices are often evaluated in terms of their throughput, as measured by Fitts ' Law, and by their resolution. However, little effort has been made to understand the limit of resolution that is controllable or “usable ” by the human using the device. What is the point of a 5000 dpi computer mouse if the human motor control system is far from being able to achieve this level of precision? This paper introduces the concept of a Device's Human Resolution (DHR): the smallest target size that users can acquire with an ordinary amount of effort using one particular device. We report on our attempt to find the DHR through a target acquisition experiment involving very small target sizes. Three devices were tested: a gaming mouse (5700 dpi), a PHANTOM (450 dpi), and a freespace device (85 dpi). The results indicate a decrease in target acquisition performance that is not predicted by Fitts ' Law when target sizes become smaller than certain levels. In addition, the experiment shows that the actual achievable resolution varies greatly depending on the input device used, hence the need to include the “device ” in the definition of DHR

Selection-Based Mid-Air Text Entry on Large Displays

Abstract. Most text entry methods require users to have physical devices within reach. In many contexts of use, such as around large displays where users need to move freely, device-dependent methods are ill suited. We explore how selection-based text entry methods may be adapted for use in mid-air. Initially, we analyze the design space for text entry in mid-air, focusing on singlecharacter input with one hand. We propose three text entry methods: H4 Mid-Air (an adaptation of a game controller-based method by MacKenzie et al. [21]), MultiTap (a mid-air variant of a mobile phone text entry method), and Projected QWERTY (a mid-air variant of the QWERTY keyboard). After six sessions, participants reached an average of 13.2 words per minute (WPM) with the most successful method, Projected QWERTY. Users rated this method highest on satisfaction and it resulted in the least physical movement

Possibility and challenges of conversion of current virus species names to Linnaean binomials

Botanical, mycological, zoological, and prokaryotic species names follow the Linnaean format, consisting of an italicized Latinized binomen with a capitalized genus name and a lower case species epithet (e.g., Homo sapiens). Virus species names, however, do not follow a uniform format, and, even when binomial, are not Linnaean in style. In this thought exercise, we attempted toconvert all currently official names ofspecies included in the virusfamily Arenaviridae and the virus order Mononegavirales to Linnaean binomials, and to identify and address associated challenges and concerns. Surprisingly, this endeavor was not as complicated or time-consuming as even the authors of this article expected when conceiving the experiment