Toward the end a recent project, a client of mine insisted on a wording change just prior to the pilot but after usability testing. It was a subtle change, a single word difference, but my intuition told me that it would make the entire prompt (and even the entire voice user interface) more ambiguous and tear down my carefully crafted organizational scheme. My data told me that the design was working as intended. I pushed back, but the client was adamant. So, we collected more data to compare the two prompts. My predictions of inappropriate user behavior were right, but the data about the specifics of user response to the "new" prompt still surprised me.
I asserted in my previous column that intuition isn’t how our field will build its credibility, but it is part of how we need to build better designs.
For VUI designers (VUIDs), intuition is more than knowing about ambiguity, grammaticality, or equivalence. Intuition has several components: flexibility, interpersonal sensitivity, communicative self-control, and sonic creativity. The more components she possesses, the greater the likelihood a VUID will be successful and correctly predict design outcomes.
• Flexibility is skill in creating alternative designs that have similar outcomes. Knowing how subtle differences in phrasing will impact user response and understanding the most critical pieces of a particular prompt will help a designer appropriately reject some alternatives and favor others. It also allows a VUID to be linguistically creative in the face of limited choices.
• Interpersonal sensitivity is the ability to combine speech/language cues in a way that meets the needs and expectations of the average user. It’s knowing what’s socially appropriate and what’s not. Because our job is to model human conversation, good designers understand that every word, phrase, sound, and silent pause contributes to the user’s perception of an interface, varies relative to its context, and impacts user behavior.
• Communicative self-control is the ability to design beyond (or in spite of) a designer’s own interpersonal skills and preferences. Consider two VUIDs: one an assertive male who holds the floor, uses an active voice, and speaks with a dominating style; the other a relatively shy, minimally initiating female who uses tag questions and indirect phrasing. If each creates a typical VUI for customer service, the design burden falls on the male because his aggressive communication style has fewer characteristics in common with typical customer expectations from a VUI, where the hallmark is a polite conversation with deference to the customer. There will be more negative user perceptions if the male designer uses himself as a communicative model for his VUI. He must use greater self-control to write in a way that is relatively unlike his own personal skills.
• In some applications, sonic creativity allows a designer to envision a unique, interesting auditory environment and realize it much in the way a soundtrack or sound effects might be developed for a movie. Today, the audio environment for many VUIs is quite constrained, but in our evolving multimodal future, this skill will have increasing importance for designers.
Back It Up
These personal traits are part of the skill set that both vendor and client companies hire VUIDs to access. However, intuition alone will not do our job. Project methodologies must also allow time and budget for validating intuition with actual user feedback.
The most desirable situation is to have a flexible, sensitive, creative, and self-controlled designer who supports design decisions with data collection. The most problematic situation occurs when a designer with relatively poor intuition doesn’t do user research at all or does it badly. The current reality is that we often just hope for the best or fail to recognize intuition as part of the VUID skill set and, adding insult to injury, then ax usability testing when schedules get tight. This is tantamount to letting a random person design your Web site without actually checking that he has any visual design skill, then deploying the site with only a hope that his creation is something other than obnoxious.
We’ve heard increasing calls in this column and elsewhere for more user research and data collection. We need to keep beating that drum. And remember: Intuition does have a role to play in the designer’s toolbox. It’s a major asset our clients are paying for, so we need to foster and promote this skill. Intuition is not the only tool, but it sure makes effective VUI design a heck of a lot easier.
Melanie Polkosky, Ph.D., is a social-cognitive psychologist and speech-language pathologist who has researched and designed speech, graphic, and multimedia user experiences for more than 12 years. She is currently a human factors psychologist and senior consultant at IBM. She can be reached at firstname.lastname@example.org.