[Eternal Student (OP)]

Hi.

   I'm not a very observant person but it's come to my attention that after each thread there's a section that claims to identify "similar topics".   
1.   Is that new or was I really not paying attention?
2.   Does anyone know what criteria are used to identify similar topics?

Here's an example:
    Original post:    "How do you calculate the capacitance of two unusually shaped plates?"   which, naturally enough was about the capacitance of two plates.

    The Similar topics suggested included:
a)   "Can I Use Washing Up Liquid To Wash Hands And Hand Soap To Wash Plates?"
b)   "How long must a prism-shaped corridor be to render a light-source invisible?"

My best guess is that an algorithm is matching some words like "shaped" and "plates" that appeared in the title.

Best Wishes.

LATE EDITING:     ?   It doesn't seem to happen in the "Just Chat" section.    Check out the main sections to see what I mean.

[Origin]

   I'm not a very observant person but it's come to my attention that after each thread there's a section that claims to identify "similar topics".   
1.   Is that new or was I really not paying attention?

Yeah, it's been there as long as I've been a member.

[Halc]

It's been there forever, and it seems to be a simple best-match on what it sees as keywords.

    The Similar topics suggested included:
a)   "Can I Use Washing Up Liquid To Wash Hands And Hand Soap To Wash Plates?"
b)   "How long must a prism-shaped corridor be to render a light-source invisible?"

The first one obviously matched 'plates', but no clue why it thought b) should be on the list.

[Eternal Student (OP)]

Hi.
    Thanks for all the replies.
 
    Well, the suggested similar topics don't seem to be too useful or selected by a sophisticated system.  So I guess I'm not too concerned about only having just noticed it exists.

Best Wishes.