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Beyond Usability: It Ain’t The Only Outcome That Matters!. Melanie D. Polkosky, Ph.D., CCC-SLP Social/Cognitive Psychologist. Presentation Goals. To identify 4 factors that are critically important to successful speech implementations
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Beyond Usability:It Ain’t The Only Outcome That Matters! Melanie D. Polkosky, Ph.D., CCC-SLP Social/Cognitive Psychologist
Presentation Goals • To identify 4 factors that are critically important to successful speech implementations • To describe the role of users’ expectations in creating positive outcomes with speech • To identify specific expectation types that are handled by effective applications • To identify items to prioritize in your next VUI design
What is Usability? • Ease of use • The design and deliverance of useful, usable, desirable, easy-to-learn solutions that have consistent functions that allow people to do what they want to do and are well-liked (Gould) • Nielson (1993) criteria: learnability, efficiency, memorability, errors, satisfaction • ISO 9241-11 - [Usability refers to] the extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use."
Speech Usability must… • Account for broad perspectives on communication (communication, social psychology, cognitive psychology, services marketing, speech science, human factors, linguistics, esp. pragmatics) • Address common practice issues (e.g., customer satisfaction) • Create viable measurement techniques • Factor analysis = statistical method of investigating variables • Reliable and valid • Explain standard user behavior (e.g., user politeness)
So what? • Without a clear understanding of usability for speech, we could: • Prioritize incorrectly in our designs • De-emphasize or overlook important issues • Get distracted by irrelevant topics • Not measure the right outcomes • Practical VUI design will not be based on knowledge of human communication behavior • Our field will lack scientific rigor (ie., credibility)
Researching Speech OutcomesPolkosky (2005) • 862 individuals listen to 6 applications and rate 76 characteristics • Factor analysis and reliability analysis to eliminate poor items • Whittle to 25 items that group into 4 factors • What are the important outcomes of speech? • User Goal Orientation • Speech Characteristics • Verbosity • Customer Service Behavior
User Goal Orientation • The system made me feel like I was in control. • I could find what I needed without any difficulty. • I could trust this system to work correctly. • I felt confident using this system. • This system would help me be productive. • The quality of this system made me want to remain a customer of this business. • I would be likely to use this system again.
Speech Characteristics • The system’s voice was pleasant. • The system’s voice sounded like people I hear on the radio or television. • The system’s voice sounded natural. • The system’s voice sounded enthusiastic or full of energy. • The system’s voice sounded like a regular person.
Verbosity • The messages were repetitive. • The system gave me more details than I needed. • The system was too talkative. • I felt like I have to wait too long for the system to stop talking so I could say something.
Customer Service Behavior • The system used terms I am familiar with. • The system used everyday words. • The system was organized and logical. • The system spoke at a pace that was easy to follow. • The system seemed polite. • The system seemed courteous. • The system seemed friendly. • The system seemed professional in its speaking style.
The bottom line… Adhering to user EXPECTATIONS is the most important thing to do to insure a high-quality outcome with speech
What expectations? • Conversational expectations - ingrained, unconscious knowledge of how conversation works • Informative, but not more informative • True statements, clear, unambiguous and brief • Relevant • Customer service expectations - ingrained, unconscious knowledge about how service providers should act • Deferential, polite, friendly, facilitative • Service quality - the gap between expected and actual service • Other expectations - media, sequencing, task priority • Professional voice (media expectations) • User task-based prompt sequencing and organization
What else matters (beyond usability)? • Adhering to users’ expectations about conversation and customer service • User personality characteristics • Age and gender • Inherent novelty seeking • Social skills (sensitivity) • Need for interaction with a service provider • Providing a pleasurable listening environment
How to design based on this research… • Highest priority on understanding users’ goals with the system • Does sequencing/organization match what users want? • Question, question, question directives from The Business about sequence, what users know • Pre-design (concept phase) user analysis and needs assessment • Cognitive walkthrough or usability testing a must • Next highest priority on finding a high-quality, natural voice talent and coaching him/her effectively • Avoid task irrelevant messaging or “over-explaining” • Don’t design a ‘persona,’ design a customer service provider • Learn more about conversation and social expectations - critical knowledge • Do not underestimate the impact of non-user knowledge and assumptions by the design team - it has the power to break your application