Designing Effective Speech Interfaces

Confirmations

Confirmations are questions you ask of the user to be sure that the user has been heard correctly. We discuss here guidelines for using effective confirmations.

Use Confirmations Appropriately

Since there are many errors associated with the computer recognizing human speech, you may have to use confirmation questions to assure that the computer has heard the right phrase or message. Here is an example:

System: “What do you want to do next?”

User: “I want to schedule an appointment with my manager.”

System: “Do you want to set up an appointment?”

User: “Yes.”

You have to balance the cost of making an error with the extra time and annoyance in requiring the user to confirm a lot of statements.

Ask for Clarifying Information

If the computer cannot figure out what the user wants to do, have it ask a clarifying question. For example, consider the dialog in the previous section. If the user's final response has more than one possible meaning, the computer could ask, “Do you want to set up an appointment or contact the person by phone?”

Use Confirmations for Destructive Actions

If the user's action is destructive, require a confirmation.

If the user's action is destructive or will delete large amounts of information, require a confirmation. However, you can minimize the use of confirmations with expert users.

Be Specific

If the system does not recognize what the user has spoken, be specific about what the system needs. Use “Please repeat the date again,” rather than, ...