Answering Why and Why Not Questions in User Interfaces Brad Myers, David A. Weitzman, Andrew J. Ko, and Duen Horng Chau Presented By: Craig Prince and Alan Liu CSE590H Autumn 2007

Brad Myers 1987 – Ph.D. from U. of Toronto 1987 to 1995 – (Senior) Research Scientist @ CMU-CS 1995 to present – Senior Research Scientist, Associate Research Professor, and Professor @ CMU-HCII Some Research Interests: End-User/Natural Programming and PBD Handheld Interfaces Quality of Life Technology User Interface Design Tools

Answering Why and Why Not… Contributions: Interaction Design Implementation Framework Gulf of Evaluation Interpreting what one sees on the screen and fix it if it’s not what the user intended Complementary to Gulf of Execution?

Why and Why Not…based on Command History

Why or Why Not…based on Selected Object

Answer to Why or Why Not

Implementation Command-Object Model (Crystal) Commands are used for Undo and Why/Why Not questions Commands know their dependent properties Commands know the controls which change them

Designer’s Role Have to design your application to follow a command-object model Designer needs to pick out level of granularity Needs to determine when to include “why not” questions 10% more code?

User Study: Example Task 1. Type in the following sentence “The abbreviation fl. oz. stands for fluid ounce.” 2. You notice that the word processor has capitalized some characters for you, but you don’t want this to happen. 3. Your task is to make the automatic capitalization not happen again. 4. When you think you’re done, type “fl. oz. stands” again to make sure it works.

Results

Discussion 1 What types of applications do you think this would work well for? Which would it not? Is it just bad design to not make it obvious why things happen? This system requires an application to be designed explicitly to use it, how does this effect it’s adoption?

Discussion 2 Was their user study well designed? How does their system compare to traditional help systems? Do you think their tasks were realistic? Did the user study evaluate their design or their concept?

Discussion 3 Are “why” questions the most common types of questions? Do novice users ask “why” questions? Does the shortcutting hinder learning of new features of an application? Shortcutting doesn’t bridge the gulf of execution.

Discussion 4 How could/would you use this system to explain more complex phenomenon? (E.g. “Why did the sharpen filter leave these visual artifacts?” or “Why didn’t the face detector detect that face?”)