Flawed Boolean Logic in Logos 6

Rod Bergen
Rod Bergen Member Posts: 251
edited November 20 in English Forum

Is boolean logic searching properly implemented in Logos 6?

Here are two searches which should produce the same results:

1. (Arius OR arianism) WITHIN 5 WORDS (writing* OR manuscript* OR literature)

2. (Arius WITHIN 5 WORDS (writing* OR manuscript* OR literature)) OR (arianism WITHIN 5 WORDS (writing* OR manuscript* OR literature))

But they don't.  The first generates 980 results while the second search produces 698 results.

I am used to searching in a professional search database where boolean logic is properly implemented (and in which the above search would work).

This is where a lack of a proper manual is very frustrating.

Comments

  • Lee
    Lee Member Posts: 2,714

    I agree.

  • Graham Criddle
    Graham Criddle MVP Posts: 32,636

    What happens if you replace the OR inside parentheses with "," as per https://wiki.logos.com/Detailed_Search_Help#Using_lists 

  • Rod Bergen
    Rod Bergen Member Posts: 251

    What happens if you replace the OR inside parentheses with "," as per https://wiki.logos.com/Detailed_Search_Help#Using_lists

    (Arius,  arianism) WITHIN 5 WORDS (writing*, manuscript*, literature) - 114 results.

  • Dave Hooton
    Dave Hooton MVP Posts: 35,767

    Yes, fewer results without the search parameter "WORDS" being included!

    Boolean terms do not work with Proximity terms, so the (list, next word, ...) has to be used where you think OR can be used.

    If you are thinking about AND, use the implicit AND of proximity e.g.

      meaning WITHIN 6 WORDS inconsistent WITHIN 10 WORDS expression

    rather than

     (meaning AND expression) WITHIN 10 WORDS inconsistent

    Dave
    ===

    Windows 11 & Android 13

  • Rod Bergen
    Rod Bergen Member Posts: 251

     Yes, fewer results without the search parameter "WORDS" being included!

    Boolean terms do not work with Proximity terms, so the (list, next word, ...) has to be used where you think OR can be used.

    If you are thinking about AND, use the implicit AND of proximity e.g.

      meaning WITHIN 6 WORDS inconsistent WITHIN 10 WORDS expression

    rather than

     (meaning AND expression) WITHIN 10 WORDS inconsistent

    So what you are effectively saying is that parentheses are useless in Logos 6?

    I'm not sure that I understand what you are getting at with your expression - "meaning WITHIN 6 WORDS inconsistent WITHIN 10 WORDS expression"

    Can you take the search that I posted above and express it in a way that works?

    Straight AND searches are almost useless given the size of most of the books that are being searched.  The use of proximity searches is almost mandatory.  So having proximity searches crippled is a very limiting feature of Logos 6.

  • Graham Criddle
    Graham Criddle MVP Posts: 32,636

    Not Dave but my thoughts

    Taxee said:

    So what you are effectively saying is that parentheses are useless in Logos 6?

    No - but they don't function as one might expect if thinking about them in Boolean Logic terms. They are used to denote lists of terms.

    Taxee said:

    I'm not sure that I understand what you are getting at with your expression - "meaning WITHIN 6 WORDS inconsistent WITHIN 10 WORDS expression"

    Dave is saying that the way to search for proximity is to treat each term separately so "find where meaning is within 6 words of inconsistent which is also within ten words of expression"

    Taxee said:


    Straight AND searches are almost useless given the size of most of the books that are being searched.  The use of proximity searches is almost mandatory.

    Agreed

    Taxee said:

    Can you take the search that I posted above and express it in a way that works?

    I'll have a go at that in a separate reply

  • Graham Criddle
    Graham Criddle MVP Posts: 32,636

    Taxee said:

    Can you take the search that I posted above and express it in a way that works?

    I think - from your example and explanation - you are trying to find where either of "Arius" or "arianism" are within 5 words of "writing" or "manuscript" or "literature". Is that correct? (I'm ignoring the wildcard terms as I don't think that's the issue here)

    If so, then, following my suggestion above I get the string you showed a few posts earlier

    (Arius,  arianism) WITHIN 5 WORDS (writing, manuscript, literature)

    This gives me 46 results which all seem to match the criteria.

    If I separate them out - doing the search for "Arius" separately from the search for "arianism" I get 28 and 18 results respectively which suggests that the complete term is working correctly.

    This seems to be working - do you see any issues?

  • Bradley Grainger (Logos)
    Bradley Grainger (Logos) Administrator, Logos Employee Posts: 11,969

    In the current query parser, "OR" and "," are not synonymous; only "," can be used within the operands of proximity operators. We have a case in our bug tracking system to relax this restriction, so the first query you wanted to write will work as expected. I've added a link from that case to this thread.

  • Rod Bergen
    Rod Bergen Member Posts: 251

     In the current query parser, "OR" and "," are not synonymous; only "," can be used within the operands of proximity operators. We have a case in our bug tracking system to relax this restriction, so the first query you wanted to write will work as expected. I've added a link from that case to this thread. 

    Thanks, Bradley.


  • Philana R. Crouch
    Philana R. Crouch Member, Logos Employee Posts: 4,597

    Taxee said:

    Is boolean logic searching properly implemented in Logos 6?

    Here are two searches which should produce the same results:

    1. (Arius OR arianism) WITHIN 5 WORDS (writing* OR manuscript* OR literature)

    2. (Arius WITHIN 5 WORDS (writing* OR manuscript* OR literature)) OR (arianism WITHIN 5 WORDS (writing* OR manuscript* OR literature))

    But they don't.  The first generates 980 results while the second search produces 698 results.

    I am used to searching in a professional search database where boolean logic is properly implemented (and in which the above search would work).

    This is where a lack of a proper manual is very frustrating.

    This is now fixed in 6.14 Beta 2

  • Rod Bergen
    Rod Bergen Member Posts: 251

    This is now fixed in 6.14 Beta 2

    Thank you!  For those of us who are used to search engines that use full Boolean logic, this will provide significantly more flexibility when searching.