Systems aren't adaptable

Novices and experts don't need the same type of explanation. Much research has gone into ``adaptable systems'' which adapt their explanation to the user's skill. This incidentally can apply to programs other than expert systems, and I'll assume it does in the rest of this section. For example, operating systems or databases whose error messages adapt to the user's knowledge.

Building such systems is tremendously difficult. Firstly, you need to find out how capable the user is. That's not easy when the only channel is his keyboard responses. Compare with with all the information a human expert can acquire about his client.

Secondly, you need to know something about the user's intentions and goals. For example, suppose you have a computer filing system, and the user asks to delete a file that doesn't exist. Possible reasons for his action:

• He has made a genuine typing error: e.g. typed 1 for I.
• He has forgotten what the file was called.
• He knows what the file is called; to save typing he tried to abbreviate its name, but did so wrongly (e.g. assuming he could leave the .DOC bit off a file with that extension).
• He's got the file name itself right, but the directory wrong.
• He thought he'd created the file with an earlier command, but he used that command incorrectly and it failed to create the file. E.g. a botched edit.
• He thought he'd created the file with an earlier command, but he used that command incorrectly and it gave the file a name different from what he expected.

• Say 'Error'?
• Give a ten-line essay on the exact syntax of filenames?
• Display a list of all the files he owns?
• Keep a log all his previous commands, and search for any that went wrong, then try to work out if any of these failed to create a file he intended to create?