Marian G. Williams
Has also published under the name of:
"Marian Williams"
Publications by Marian G. Williams (bibliography)
Cogdill, Sharon, Fanderclai, Tari Lin, Kilborn, Judith and Williams, Marian G. (2001): Backchannel: Whispering in Digital Conversation. In: HICSS 2001 2001. .
Altom, Mark W. and Williams, Marian G. (eds.) Proceedings of the ACM CHI 99 Human Factors in Computing Systems Conference May 15-20, 1999, Pittsburgh, Pennsylvania.
Williams, Marian G. and Buehler, J. Nicholas (1999): Comparison of Visual and Textual Languages Via Task Modeling. In International Journal of Human-Computer Studies, 51 (1) pp. 89-115.
“In order for comparative studies of programming languages to be meaningful, differences between the languages need to be carefully studied and well understood. Languages that appear to differ only in syntax (for example, visual vs. textual syntax) may in fact differ greatly in usability. Such differences can confound comparative studies unless they are controlled for. In this paper, we examine the usefulness of fine-grained task modeling for studying the usability of programming languages. We focus on program entry, and demonstrate how to create models of program entry tasks for both visual and textual languages. We also demonstrate how to derive performance time estimates from the models using keystroke-level analysis. A by-product of the model building is a collection of functional-level models that can serve as building blocks for modeling higher-level visual programming tasks. We then report on a comparative study of languages with the same semantics but different syntax (visual and textual). Model-based time predictions of program entry tasks were compared to observed times from an empirical study. The time estimates for the visual condition greatly overestimated the observed times. The primary source of the overestimates appeared to be the time estimate for pointing with the mouse. We then look at three different approaches to improving program entry models. We report on a separate study to calibrate the mouse-pointing time estimate, and demonstrate improved correlation between predicted and observed times with the new estimate. We also apply task modeling to program editing activities, in order to model error recovery behavior during program entry. Finally, we discuss language-specific customization of the keystroke-level operator for mental preparation. We conclude that task modeling is a useful technique for studying differences in the usability of programming languages at the keystroke level.”
© All rights reserved Williams and Buehler and/or Academic Press
Altom, Mark and Williams, Marian G. (1998): CHI 99: The CHI Is the Limit. In ACM SIGCHI Bulletin, 30 (3) pp. 64-65.
Williams, Marian G. and Sears, Andrew (1998): HCI Education and CHI 98. In ACM SIGCHI Bulletin, 30 (4) pp. 9-15.
Traynor, Carol and Williams, Marian G. (1997): A Study of End-User Programming for Geographic Information Systems. In: Empirical Studies of Programmers - Seventh Workshop October 24-26, 1997, 1997, Alexandria, Virginia. pp. 140-156.
“This paper presents an empirical study of a programming by demonstration language for a geographic information system (GIS). The long-term goal of the project is to enable non-technical end users to exercise the capabilities of a GIS without having to learn the technical concepts that are embedded in most traditional GIS interfaces (Traynor&Williams, 1995). The programming by demonstration language is an extension of the Pursuit language introduced by Modugno for file management in the Macintosh Finder (Modugno, Corbett&Myers, 1996). The extensions permit the display of textual information in tables and of cartographic information on a map. The purpose of the preliminary study reported here was to determine whether programmers could read, edit, and create programs in the programming by demonstration language. Subjects' performance on the program comprehension tasks and the editing of simple programs was error free. Errors in the editing of more complex programs and in the program creation tasks indicate that some of the language constructs may need to be redesigned. Subjects' opinions of the programming by demonstration language were generally positive, as indicated by post-test questionnaires. We conclude that programming by demonstration is a promising approach for a GIS interface.”
© All rights reserved Traynor and Williams and/or ACM Press
Williams, Marian G. and Buehler, J. Nicholas (1997): A Study of Program Entry Time Predictions for Application-Specific Visual and Textual Languages. In: Empirical Studies of Programmers - Seventh Workshop October 24-26, 1997, 1997, Alexandria, Virginia. pp. 209-223.
“Creating and editing a computer program involves creative design work, but also involves the mechanical work of entering the code. Thus, program entry time needs to be taken into account in comparative studies of program creation and editing tasks using textual and graphical languages. We present a study of program entry time for application-specific graphical and textual languages with equivalent functionality. First, typical program entry tasks were modeled, and time predictions were calculated from the models. Then a small empirical study was performed to check the validity of the models. There was a high positive correlation (r=.927, p < .005) between observed execution times and predicted times. In addition, there was a significant difference (p < .05) between the execution times for the graphical and textual conditions for each task, and the difference was always in the direction predicted by the models. Finally, the prediction model was fine-tuned to produce even greater correlation with observed results. This study suggests that our upcoming study of learning outcomes in time-limited training situations, which will use the graphical and textual languages reported on here, does not have a systematic bias against either language in the effort required for program entry. It also provides evidence for the usefulness of keystroke level modeling for comparison of program entry tasks and suggests that related kinds of models may be useful for comparing the performance of other kinds of programming tasks.”
© All rights reserved Williams and Buehler and/or ACM Press
Sears, Andrew and Williams, Marian G. (1997): HCI Education and CHI 97. In ACM SIGCHI Bulletin, 29 (4) pp. 9-12.
Williams, Marian G. (1995): Local SIGs: The Rocky Mountain Climbing Challenge. In ACM SIGCHI Bulletin, 27 (4) pp. 10-11.
Williams, Marian G., Ledder, William A., Buehler, J. Nicholas and Canning, James T. (1993): An Empirical Study of Visual Labs. In: Proceedings of the 1993 IEEE Workshop on Visual Languages August 24-27, 1993, Bergen, Norway. pp. 371-373.
Williams, Marian G. and Begg, Vivienne (1993): Translation between Software Designers and Users. In Communications of the ACM, 36 (6) pp. 102-103.
Williams, Marian G., Smith, Stuart and Pecelli, Giampiero (1990): Computer-Human Interface Issues in the Design of an Intelligent Workstation for Scientific Visualization. In ACM SIGCHI Bulletin, 21 (4) pp. 44-49.
“The long-range goal of our research is to create an intelligent assistant for interactive scientific data visualization via both sight and sound. There are a variety of computer-human interface (CHI) issues that are unique to our approach to interactive visualization. It is upon these issues that we focus here. In this paper, we: (1) describe the approach to interactive visualization taken by the project which is the context of our work; (2) specify the CHI issues that are peculiar to this approach; (3) summarize the current capabilities of our workstation for performing human factors experiments; (4) describe the research plan we have developed for learning how to provide a user with intelligent assistance for dealing with those issues; (5) present a representative pilot study that has contributed useful information; (6) summarize the results of our pilot studies; and (7) discuss the direction of our future work. We do not claim to be solving the general case of how to provide intelligent assistance for scientific visualization. We do, however, expect that the progress we make in one visualization environment will contribute to understanding of the general case.”
© All rights reserved Williams et al. and/or ACM Press
Grinstein, Georges G., Pickett, Ronald M. and Williams, Marian G. (1989): EXVIS: An exploratory visualization environment. In: Graphics Interface 89 June 19-23, 1989, London, Ontario, Canada. pp. 254-261.
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Changes to this page (author)
10 Feb 2010: Enabled abstracts to be shown on Marian G. Williams's author page.18 Aug 2009: Author was edited 03 Jul 2009: Author was edited (approved by an editor)
16 Jun 2009: Author was edited
12 Jun 2009: Author was edited
24 Jun 2007: Author was edited
24 Jun 2007: Author was edited
24 Jun 2007: Author was edited
24 Jun 2007: Author was added to the bibliography
23 Jun 2007: Author was edited
28 Apr 2003: Added the author to the bibliography
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