When you decide to build a speech-enabled IVR application you hear a lot about the Voice User Interface, or VUI, and the process of designing it, which we call VUI Design. You hear that good VUI design is a critical success factor for your speech application. So you’d like to know a little more about what constitutes good VUI design and how you can be sure your VUI will get it.
Unfortunately, there are lots of ideas about what constitutes good VUI design, and lots of arguing about who is right. Most likely there is no single “best” approach to VUI design. The one thing that everyone does agree on is that good VUI design is user-oriented.
We want to use speech because it is so easy and natural, but computers have no native talent for it at all. A caller’s patience runs out fast when any two year old could have understood what they just said, but the computer cannot. That’s why VUI design is a key success factor for your speech application. Done right, it increases both automation and customer satisfaction. The question is how to get it done right. The answer is to embed the caller viewpoint into the entire design process, from start to finish.
The VEXIS Data Driven Design™ Process
Let’s leave VUI design aside for moment, and talk about our overall design process, which we call VEXIS Data Driven Design. It has a simple mantra: “Follow the data.” What this means is: Focus on the data at every step of the design process.
When we say “the data”, we mean exactly that – the actual data elements that the application will read and write to/from your databases, such as DateOfService, MailingAddress, CurrentBalance, etc. We also mean the data transactions that will be used by the application to access those elements.
Why focus on the data? There are three good reasons:
Reason #1: Your data encapsulates your business. Think about it. What you store on your backend is exactly the information you need to conduct your business. Furthermore, your business rules are already built into the ways you access that data (such as CSR desktop, or web server) and give customers access to it (such as mailed statements, or web GUI).
Reason #2: Data Driven Design is not new. It is a well-established software design practice. From a software perspective, “the data” is simply the inputs and outputs from the application, which always play a central role in software design:
• The core of a high-level functional design (the first stage in the Data Driven design process) is the list of data transactions that are in scope for the application.
• The next design stage, the callflow design, lists every piece of data that is input by the caller and every piece of data that is played out to the caller or used to drive the application logic. It defines the inputs and outputs for each data transaction, and shows the order in which it all occurs.
• The final design stage, the Detailed Design Specification which provides the complete application design, is really just the full details about “the data”. We specify the application logic according to data input by the caller or retrieved about the caller. We write out the exact scripting of the prompts based on the data we want to get from the caller and the data we want to announce to them. Every single fact about every piece of data that we need to know to build the application is included.
Reason #3: There’s one more really great thing about Data Driven Design – when you apply it to VUI Design, it produces straightforward and simple designs which are highly usable and efficient for the caller.
VUI Design By “The Data”
We were surprised to find that a software design methodology worked well for VUI design; which is supposed to be all about “human factors”. But it’s an obvious approach if you think about it.
The reason is that your callers already know “the data”. Even if they have never used the IVR, they know what the data elements are from interacting with CSRs and from the way the data is presented in mailings and on the web. In order to make your business work, you have already organized “the data” in a way that customers can understand, and you can leverage that now.
However, the caller’s view of the data is usually much more simplistic and intuitive than the view of the data from an Information Technology (IT) perspective (which is the reason you need VUI Design in the first place). In order to account for this within our Data Driven Design process, we add the user view into “the data” that guides the entire process.
For example, in the functional design, the data transactions must be as clear from a user point of view as they are from a logical point of view. Keep them familiar whenever possible (i.e. do the same kinds of things a CSR would do). And keep them simple and understandable.
In the callflow design, make sure the data elements are ones the callers are familiar with and present them in a familiar order. Only collect relevant data. Use the same name for a data element that is used by the CSRs and in your mailed materials.
In the Detailed Design Specification, focus the scripting on clear elicitation of the data you want the caller to input (for example, don’t put too many options in one menu) and clear announcement of the data you output to the caller (for example, repeat confirmation numbers a couple of times in the outgoing message).
By adding the caller’s viewpoint of the data to the Data Driven Design process, we build usability into the process itself. If you stay focused on the data from the caller perspective, the VUI Design almost takes care of itself.
I like to imagine one day every year at VEXIS where the design team would all come in wearing fur shorts and carrying huge clubs that say “It’s the data, stupid”. Then we would proceed to bash each other over the head with the clubs to remind us to focus on the data for the next year. Of course, we don’t do this – we’re not allowed to wear fur shorts to the office. But, seriously, at VEXIS, when we encounter design issues, we do always try to remember to look to “the data” for understanding and inspiration!
Keith Rolle, Chief VUI Architect