Optimum query delay for autocomplete

Question

In a yui AutoComplete or similar how many milliseconds are you using as query delay (time between the last key input and the request to the server)?

I recently changed the default value of an autocomplete cotrol similar to yui's from 750ms to 280ms using Keystroke-Level Model as a reference.

Any other useful references out there?

Answer 1

It really depends on your purpose, I think. In my scenario I wanted them to not be intrued on if they knew exactly what they wanted. If they hesitate at all, help is there. For that, I used .3 or .5.

If you want to make their life easier by suggesting completions you can set it to 0 like Google does.