Part 1. Definition
Evaluate the similarity between them and classify them into classes from 0-5 as follows:
0 : The two sentences are completely dissimilar.
1 : The two sentences are not equivalent, but are on the same topic.
2 : The two sentences are not equivalent, but share some details.
3 : The two sentences are roughly equivalent, but some important information differs/missing.
4 : The two sentences are mostly equivalent, but some unimportant details differ.
5 : The two sentences are completely equivalent, as they mean the same thing.
Part 2. Example
Sentence 1: A plane is taking off. Sentence 2: An air plane is taking off.
Answer: 5
Explanation: Here both statements are talking about the same thing hence it will be classified as a 5.
Part 3. Exercise
Sentence 1: Security experts are warning that a new mass-mailing worm is spreading widely across the Internet, sometimes posing as e-mail from the Microsoft founder. Sentence 2: A new worm has been spreading rapidly across the Internet, sometimes pretending to be an e-mail from Microsoft Chairman Bill Gates, antivirus vendors said Monday.
Answer:
5