Sunday, September 13, 2009

Randomising prompts...

Zeno from the VUIDs group asked the following question:

I am thinking about Random Prompting. For me, this feature always has two sides:(1)It can make an application much more human-like, since humans also tend to formulate a certain question/information in different ways.(I know, there are very contradictory opinions, wheter a system should behuman-like or not. But IF you want to have system human-like, Random Promptingcould be an effective way and it's easy to implement). (2) On the other hand, it hinders the user from creating a "mental map" of thesystem. This could especially be bad for power-users but also for situations,where the user returns to a certain place within one dialog/call.Does anyone have had experiences with random prompting, or even startedexperiments? Would be very interesting...

I would say that randomization for the sake of variability is not a compelling reason -- in fact, I would say it is self defeating since the caller may be thrown off by the seemingly purposeless variability. On the other hand, purposeful variability is a good thing when done right -- e.g., personalization. I would rather that the system anticipated my need and proposed an option rather than safely provide me with a main menu -- e.g., "Are you calling about the status of your recent on-line purchase?" I think in such cases, the potential fast-tracking is worth the mental map disruption....

An interesting response was from Eduardo Olvera, who wrote:

Even though I agree with the points mentioned below about Dynamic Prompting and Design in general, I think there are actual appropriate uses of random prompts (by random meaning prompts that are pulled from a pool of possible prompt alternatives, not prompts that are driven by context or dynamic values). For example: (1) During user identification and/or authentication - asking callers to repeat a random sequence of letters, or asking a random security question from a set, for the purpose of increasing the security of a system (e.g. if someone listens to the answer to your question, they shouldn't be able to call back in and authenticate with the answer they just heard)

(2) To provide tips and/or information once a caller has successfully completed a task or when, based on the context, it makes sense to present information the user might not be aware of - for example, if a system contains many features, or is constantly updated/enhanced, having "By the way" type of prompts at the end once a task has been completed and the user is likely to simply hang-up, it is sometimes useful to present those tips to educate callers about features/services they might not know about

(3) When attempting to help users recover from a situation that might take place so early in a call that we might not know anything about the intent, which the user might visit more than once, and which furthermore might have so many different possibilities that it would be hard to only offer a narrow set of subchoices. For example, on a Natural Language Main Menu Router (SLM), sometimes it is helpful to have a handful of random prompts, each with a slightly different set of suggestions/examples

(4) When trying to break the monotony of repetitive exit prompts that serve a particular purpose but that might not have a direct impact on the outcome of the interaction. For example, on a learning system, if you're asking your user to follow a certain sequence of steps and you're trying to encourage them along the way, it's helpful to have a random set of prompts with various "encouraging" short messages like "That's it", "Perfect", "Nice", "Good job", etc. so that you don't play back the same message over and over again, making it even more apparent that you're dealing with an automated system