How do I approximate “Did you mean?” without using Google?

Question

I am aware of the duplicates of this question:

• How does the Google “Did you mean?” Algorithm work?
• How do you implement a “Did you mean”?
• ... and

Answer 1

Impressive tutroail one how its work you can found here http://alias-i.com/lingpipe-3.9.3/demos/tutorial/querySpellChecker/read-me.html.

In few word it is trade off of query modification(on character or word level) to increasing coverage in search documents. For example "aple" lead to 2mln documents, but "apple" lead to 60mln and modification is only one character, therefore it is obvious that you mean apple.