Steven J. Castellucci

IBM · IBM Security (Markham ON)

Touch is the predominant method of text entry on mobile devices. However, these devices also facilitate tilt-based input using accelerometers and gyroscopes. This paper presents the design and evaluation of TiltWriter, a non-touch, tilt-based text entry technique. TiltWriter aims to supplement conventional techniques when precise touch is not conve...

In this two-session course, attendees learn how to conduct empirical research in human-computer interaction (HCI). This course delivers an A-to-Z tutorial on designing a user study and demonstrates how to write a successful CHI paper. It would benefit anyone interested in conducting a user study or writing a CHI paper. Only general HCI knowledge is...

In this two-session course, attendees will learn how to conduct empirical research in human-computer interaction (HCI). This course delivers an A-to-Z tutorial on designing a user study and demonstrates how to write a successful CHI paper. It would benefit anyone interested in conducting a user study or writing a CHI paper. Only general HCI knowled...

The popularity of mobile devices with large screens is making single-handed interaction difficult. We propose and evaluate a novel design point around a tilt-based text entry technique which supports single handed usage. Our technique is based on the gesture keyboard (shape writing). However, instead of drawing gestures with a finger or stylus, use...

In this two-session course, attendees will learn how to conduct empirical research in human-computer interaction (HCI). This course delivers an A-to-Z tutorial on designing a user study and demonstrates how to write a successful CHI paper. It would benefit anyone interested in conducting a user study or writing a CHI paper. Only a general HCI knowl...

This course teaches how to pose testable research questions, how to make and measure observations, and how to design an experiment. Attendees participate in a real experiment to gain experience as both an investigator and as a participant. Most notably, attendees learn how to organize experiment results and write a CHI paper.

We introduce new metrics to help explain 3D pointing device movement characteristics. We present a study to assess these by comparing two cursor control modes using a Sony PS Move. "Laser" mode used ray casting, while "position" mode mapped absolute device movement to cursor motion. Mouse pointing was also included, and all techniques were also ana...

A touch-based text entry method was developed with the goal of reducing the attention demand on the user. The method, called H4touch, supports the entry of about 75 symbols and commands using only four soft keys. Each key is about 20 larger than the keys on a Qwerty soft keyboard on the same device. Symbols are entered as Huffman codes with most l...

We developed a text entry method for touchscreen devices using a Graffiti-like alphabet combined with automatic error correction. The method is novel in that the user does not receive the results of the recognition process, except at the end of a phrase. The method is justified over soft keyboards in terms of a Frame Model of Visual Attention, whic...

We developed an application to gather text entry speed and accuracy metrics on Android devices. This paper details the features of the application and describes a pilot study to demonstrate its utility. We evaluated and compared three mobile text entry methods: QWERTY typing, handwriting recognition, and shape writing recognition. Handwriting was t...

We evaluated and compared four input methods using the Nintendo Wii Remote for pointing tasks. The methods used (i) the "A" button on top of the device, (ii) the "B" button on the bottom of the device, (iii) the Intec Wii Combat Shooter attachment and (iv) the Nintendo Wii Zapper attachment. Fitts' throughput for all four input methods was calculat...

The pervasive use of ambiguous keypads for mobile text entry necessitates examination of their performance characteristics. This paper presents TnToolkit - a self-contained tool to calculate performance measurements for ambiguous keypads. While TnToolkit's focus is ambiguous keypads, it also works with QWERTY and on-screen keypads. By default, TnTo...

Fifteen participants completed a study comparing video game controllers for point-select tasks. We used a Fitts' law task, as per ISO 9241-9, using the Nintendo Wii Remote for infrared pointing, the Nintendo Classic Controller for analogue stick pointing, and a standard mouse as a baseline condition. The mouse had the highest throughput at 3.78 bps...

Unistrokes and Graffiti are stylus-based text entry techniques. While Unistrokes is recognized in academia, Graffiti is commercially prevalent in PDAs. Though numerous studies have investigated the usability of Graffiti, none exists to compare its long-term performance with that of Unistrokes. This paper presents a longitudinal study comparing entr...

This paper introduces UniGest, a technique that provides pointer input and text entry in a single device without occupying the display. It uses a Nintendo Wii motion-sensing remote to capture gestures that are mapped to character input. A gesture alphabet is proposed, with each gesture composed of at most two primitive motions. A web-based user stu...