Rounding: wording and algorithm
Rounding: wording and algorithm
Some posts moved from Apostrophe crimes.
> Each [thing] shall then be [maths in words], rounded to the nearest thousandth of a basis point (exact half thousandths of a basis point of yield being rounded up).
Should there be any hyphenation in the above, and if so, where? Can the parenthetical clause be both clearer and more concise?
> Each [thing] shall then be [maths in words], rounded to the nearest thousandth of a basis point (exact half thousandths of a basis point of yield being rounded up).
Should there be any hyphenation in the above, and if so, where? Can the parenthetical clause be both clearer and more concise?
- djewesbury
- Graham’s 1970
- Posts: 8165
- Joined: 20:01 Mon 31 Dec 2012
- Location: Gothenburg, Sweden
- Contact:
Re: Apostrophe crimes
1. No.
2. It's already clear and concise.
2. It's already clear and concise.
Daniel J.
Husband of a relentless former Soviet Chess Master.
delete.. delete.. *sigh*.. delete...
Husband of a relentless former Soviet Chess Master.
delete.. delete.. *sigh*.. delete...
Re: Apostrophe crimes
Should "half thousands" be "half thousandths"?
"The first duty of Port is to be red"
Ernest H. Cockburn
Ernest H. Cockburn
Re: Apostrophe crimes
Thank you. Yes, it should: fixed.DRT wrote:Should "half thousands" be "half thousandths"?
- djewesbury
- Graham’s 1970
- Posts: 8165
- Joined: 20:01 Mon 31 Dec 2012
- Location: Gothenburg, Sweden
- Contact:
Re: Apostrophe crimes
Should it be two-thousandths?jdaw1 wrote:Thank you. Yes, it should: fixed.DRT wrote:Should "half thousands" be "half thousandths"?
Daniel J.
Husband of a relentless former Soviet Chess Master.
delete.. delete.. *sigh*.. delete...
Husband of a relentless former Soviet Chess Master.
delete.. delete.. *sigh*.. delete...
Re: Apostrophe crimes
How can a number that is exact be rounded up?
Do you mean "rounded up to the nearest two-thousandth of a basis point"?
Do you mean "rounded up to the nearest two-thousandth of a basis point"?
"The first duty of Port is to be red"
Ernest H. Cockburn
Ernest H. Cockburn
- djewesbury
- Graham’s 1970
- Posts: 8165
- Joined: 20:01 Mon 31 Dec 2012
- Location: Gothenburg, Sweden
- Contact:
Re: Apostrophe crimes
The exact number 7 can be rounded up to 10.
Daniel J.
Husband of a relentless former Soviet Chess Master.
delete.. delete.. *sigh*.. delete...
Husband of a relentless former Soviet Chess Master.
delete.. delete.. *sigh*.. delete...
-
- Dalva Golden White Colheita 1952
- Posts: 3520
- Joined: 14:22 Wed 15 Dec 2010
- Location: Near Cambridge, UK
Re: Apostrophe crimes
Should probably be "exact half of a thousandth being rounded up"; two-thousandths would be confusing. basis-point might need hyphenation, I do now know.djewesbury wrote:Should it be two-thousandths?jdaw1 wrote:Thank you. Yes, it should: fixed.DRT wrote:Should "half thousands" be "half thousandths"?
Rounding: wording and algorithm
Stop chattering in class, Jewesbury, and pay attention.djewesbury wrote:The exact number 7 can be rounded up to 10.
That's why I asked the question. Is JDAW rounding up to the nearest thousandth or the nearest half of a thousandth?PhilW wrote:Should probably be "exact half of a thousandth being rounded up"; two-thousandths would be confusing.djewesbury wrote:Should it be two-thousandths?jdaw1 wrote:Thank you. Yes, it should: fixed.DRT wrote:Should "half thousands" be "half thousandths"?
"The first duty of Port is to be red"
Ernest H. Cockburn
Ernest H. Cockburn
Re: Apostrophe crimes
What I want is:
† Assume that ambiguity is being sought by evil lawyer-mathematician types. So “unambiguous” means “really utterly unambiguous”. And don’t assume that all numbers are positive.
- 50 → 50
50.0004 → 50
50.00049 → 50
50.0005 → 50.001
50.00051 → 50.001
50.0006 → 50.001
50.001 → 50.001
† Assume that ambiguity is being sought by evil lawyer-mathematician types. So “unambiguous” means “really utterly unambiguous”. And don’t assume that all numbers are positive.
Re: Apostrophe crimes
"rounded to the nearest thousandth of a basis point" does it for me. If you need more precision then perhaps "rounded to the nearest thousandth of a basis point (where greater than or equal to n.nnn5 shall be rounded up and less than n.nnn5 shall be rounded down).
"The first duty of Port is to be red"
Ernest H. Cockburn
Ernest H. Cockburn
Re: Apostrophe crimes
DRT wrote:If you need more precision
That is a yes, I do need more “precision”.jdaw1 wrote:evil lawyer-mathematician types
Is that really clearer than my earlier suggestion (because it is longer, and the repeated n’s introduce an ambiguity)?DRT wrote:"rounded to the nearest thousandth of a basis point (where greater than or equal to n.nnn5 shall be rounded up and less than n.nnn5 shall be rounded down).
jdaw1 (after correcting a typo) wrote:rounded to the nearest thousandth of a basis point (exact half thousandths of a basis point of yield being rounded up).
- djewesbury
- Graham’s 1970
- Posts: 8165
- Joined: 20:01 Mon 31 Dec 2012
- Location: Gothenburg, Sweden
- Contact:
Re: Apostrophe crimes
This is the wrong place for this discussion and you have already crowded out a true-bill spelling mistake, by Derek, whose mistakes are always most fun.
Daniel J.
Husband of a relentless former Soviet Chess Master.
delete.. delete.. *sigh*.. delete...
Husband of a relentless former Soviet Chess Master.
delete.. delete.. *sigh*.. delete...
- djewesbury
- Graham’s 1970
- Posts: 8165
- Joined: 20:01 Mon 31 Dec 2012
- Location: Gothenburg, Sweden
- Contact:
Apostrophe crimes
Now I am complaining. Precedent means nothing here.
Last edited by djewesbury on 14:18 Sat 29 Nov 2014, edited 1 time in total.
Daniel J.
Husband of a relentless former Soviet Chess Master.
delete.. delete.. *sigh*.. delete...
Husband of a relentless former Soviet Chess Master.
delete.. delete.. *sigh*.. delete...
Re: Apostrophe crimes
This is the wrong place for this discussion (other than to mention the omission of the terminal full stop).djewesbury wrote:Precedent means nothing here
-
- Dalva Golden White Colheita 1952
- Posts: 3520
- Joined: 14:22 Wed 15 Dec 2010
- Location: Near Cambridge, UK
Re: Apostrophe crimes
Your original was clear. For additional evil-lawyer satisfaction:
"Each [thing] shall then be [maths in words], rounded to the nearest thousandth of a basis point; exact half of a thousandths of a basis point of yield being rounded up."
Note, you have given several examples, but then said "And don’t assume that all numbers are positive" without confirming your intention with regard to negative numbers. Your definition would mean that (first three as per your quote, second three added by me):
50.00049 → 50
50.0005 → 50.001
50.00051 → 50.001
-50.00049 → 50
-50.0005 → 50
-50.00051 → 50.001
If this is as you intend, all is good; otherwise you would need to state that exact half of thousandths are rounded to the next thousandth away from zero, instead of rounded up, or similar.
"Each [thing] shall then be [maths in words], rounded to the nearest thousandth of a basis point; exact half of a thousandths of a basis point of yield being rounded up."
Note, you have given several examples, but then said "And don’t assume that all numbers are positive" without confirming your intention with regard to negative numbers. Your definition would mean that (first three as per your quote, second three added by me):
50.00049 → 50
50.0005 → 50.001
50.00051 → 50.001
-50.00049 → 50
-50.0005 → 50
-50.00051 → 50.001
If this is as you intend, all is good; otherwise you would need to state that exact half of thousandths are rounded to the next thousandth away from zero, instead of rounded up, or similar.
- djewesbury
- Graham’s 1970
- Posts: 8165
- Joined: 20:01 Mon 31 Dec 2012
- Location: Gothenburg, Sweden
- Contact:
Re: Apostrophe crimes
Battle lost. Quants have taken control here as elsewhere. Is nowhere safe from their meaningless ranting?
Daniel J.
Husband of a relentless former Soviet Chess Master.
delete.. delete.. *sigh*.. delete...
Husband of a relentless former Soviet Chess Master.
delete.. delete.. *sigh*.. delete...
Re: Apostrophe crimes
For negative numbers I don’t particularly care which happens, except that I don’t want to pay lawyers to squabble about it. So anything clear.PhilW wrote:you have given several examples, but then said "And don’t assume that all numbers are positive" without confirming your intention with regard to negative numbers.
Current favourite:
> Each [thing] shall then be [maths in words], rounded to the nearest thousandth of a basis point; an exact half of a thousandth of a basis point of yield being rounded up.
Re: Apostrophe crimes
I am a little unclear about what there is to squabble about. My maths qualification extends to a 98%ish score in the Scottish equivalent of an A-Level. My intuitive understanding of rounding would always result in me rounding 5 and above to 10 and below 5 to 0.
Do lawyers do it another way?
Do lawyers do it another way?
"The first duty of Port is to be red"
Ernest H. Cockburn
Ernest H. Cockburn
Re: Apostrophe crimes
Sometimes† — it depending on the instructions from the client.DRT wrote:Do lawyers do it another way?
† Except when billing the client, rounding then always being up.
Re: Apostrophe crimes
Does the method of rounding you wish to employ meet with an international standard or specific, documented academic definition? If so, reference the source.
"The first duty of Port is to be red"
Ernest H. Cockburn
Ernest H. Cockburn
-
- Dalva Golden White Colheita 1952
- Posts: 3520
- Joined: 14:22 Wed 15 Dec 2010
- Location: Near Cambridge, UK
Re: Apostrophe crimes
Sometimes it matters in order to avoid cumulative errors over analysis of large data sets, or addition of bias. For example, consider rounding a serial of positive floating point numbers; if you were to always round up to nearest integer, you would add a bias of 0.5 to the mean of the rounded data compared with the original. Rounding to the nearest integer works much better, but the if the rounding of the mid-point value always occurs in the same direction, this can cause a similar cumulative error over a large enough data set. This matters in some data processing applications.DRT wrote:I am a little unclear about what there is to squabble about.
-
- Dalva Golden White Colheita 1952
- Posts: 3520
- Joined: 14:22 Wed 15 Dec 2010
- Location: Near Cambridge, UK
Re: Apostrophe crimes
Yes, the IEEE defines standards for definition, format and rounding of floating point numbers stored in binary format (IEEE 754). Julian's case here is slightly different, since it is referring to the rounding to thousandths, though the same terminology could be used; in Julian's current definition the terminology would be "rounding to nearest, ties to +infinity", although ironically this is not one of the standard formats; "rounding to nearest, ties to even" is the default, while "rounding to nearest, ties away from zero" is simpler to explain.DRT wrote:Does the method of rounding you wish to employ meet with an international standard or specific, documented academic definition? If so, reference the source.
Re: Apostrophe crimes
There is no problem with large datasets; no standard need be followed; and I don't particularly care how rounding is done provided that it is clear, seems reasonable to a numerate lay observer, and is utterly unsquabblable.