On Sun, 18 Jan 2004 03:28:28 -0500, "Gary Warner"
wrote:


"Joe Parsons" wrote:

A nautical mile is also, precisely, 6,076.12 feet.


[HAIRSPLITTING=ON]

That's not precise--that's rounded to two decimals.
A nautical mile is, by definition, precisely 1,852 meters, as mentioned
above.
That converts to 6,076.11549 feet (which still is not precise!).
[HAIRSPLITTING=OFF]


[HAIRSPLITTING = ON AGAIN]

Actually, the statement, "A nautical mile is also, precisely, 6,076.12
feet."
IS precise. It may not be exact, but it is precise.

[HAIRSPLITTING = OFF]

Spliting of hairs

Actually, precision is how you define precision - it is a fairly
flexible term. One can be precise to two places or ten places - it
all depends on how the number is used.

Thus, I choose to be precise to 3.88451 feet - 6,080 feet it is. ;)

/Splitting of hairs

Later,

Tom
S. Woodstock, CT
----------
"My rod and my reel - they comfort me."

St. Pete, 12 Lb. Test

The concepts being wrestled with here are "precision" and "accuracy".

Precision implies repeatable results to some number of decimal places
plus or minus an uncertainty factor.

Accuracy implies the correct answer in absolute terms.

================================================== ===


On Sun, 18 Jan 2004 11:37:42 GMT, Short Wave Sportfishing
wrote:

On Sun, 18 Jan 2004 03:28:28 -0500, "Gary Warner"
wrote:


"Joe Parsons" wrote:

A nautical mile is also, precisely, 6,076.12 feet.


[HAIRSPLITTING=ON]

That's not precise--that's rounded to two decimals.
A nautical mile is, by definition, precisely 1,852 meters, as mentioned
above.
That converts to 6,076.11549 feet (which still is not precise!).
[HAIRSPLITTING=OFF]


[HAIRSPLITTING = ON AGAIN]

Actually, the statement, "A nautical mile is also, precisely, 6,076.12
feet."
IS precise. It may not be exact, but it is precise.

[HAIRSPLITTING = OFF]

Spliting of hairs

Actually, precision is how you define precision - it is a fairly
flexible term. One can be precise to two places or ten places - it
all depends on how the number is used.

Thus, I choose to be precise to 3.88451 feet - 6,080 feet it is. ;)

/Splitting of hairs

Later,

Tom
S. Woodstock, CT
----------
"My rod and my reel - they comfort me."

St. Pete, 12 Lb. Test

"Wayne.B" wrote in message
...
The concepts being wrestled with here are "precision" and "accuracy".

Precision implies repeatable results to some number of decimal places
plus or minus an uncertainty factor.

Accuracy implies the correct answer in absolute terms.

================================================== ===


On Sun, 18 Jan 2004 11:37:42 GMT, Short Wave Sportfishing
wrote:

On Sun, 18 Jan 2004 03:28:28 -0500, "Gary Warner"
wrote:


"Joe Parsons" wrote:

A nautical mile is also, precisely, 6,076.12 feet.


[HAIRSPLITTING=ON]

That's not precise--that's rounded to two decimals.
A nautical mile is, by definition, precisely 1,852 meters, as
mentioned
above.
That converts to 6,076.11549 feet (which still is not precise!).
[HAIRSPLITTING=OFF]


[HAIRSPLITTING = ON AGAIN]

Actually, the statement, "A nautical mile is also, precisely, 6,076.12
feet."
IS precise. It may not be exact, but it is precise.

[HAIRSPLITTING = OFF]

Spliting of hairs

Actually, precision is how you define precision - it is a fairly
flexible term. One can be precise to two places or ten places - it
all depends on how the number is used.

Thus, I choose to be precise to 3.88451 feet - 6,080 feet it is. ;)

/Splitting of hairs

Later,

Tom
S. Woodstock, CT
----------
"My rod and my reel - they comfort me."

St. Pete, 12 Lb. Test


Not exactly. Precision can be described to how many decimal places you go
out. Accuracy is how good is the data.

3.88451 is a precision of 5 decimal places and an accuracy of 4 decimal
places. The number can be from 3.884505 to 3.884514 And multiplying does
not increase precision, only continues the precision of the input values.
3.21 x 3.21 != 10.3041 is only accurate to 10.30. The rest of the numbers
are noise / garbage.

3.21 x 3.21 != 10.3041 is only accurate to 10.30.

correct me if I am wrong, but as I remember it 3.21 x 3.21 is only accurate to
one decimal because the factors are accurate to only 1 place. I am pretty sure
of that but it has been a while since I worried about "precision" and "double
precision" numbers.

Actually meant to post only 2 place precision. Yes is only accurate to 1
decimal place.
Bill

"JAXAshby" wrote in message
...
3.21 x 3.21 != 10.3041 is only accurate to 10.30.

correct me if I am wrong, but as I remember it 3.21 x 3.21 is only
accurate to
one decimal because the factors are accurate to only 1 place. I am pretty
sure
of that but it has been a while since I worried about "precision" and
"double
precision" numbers.

On 18 Jan 2004 18:36:14 GMT, (JAXAshby) wrote:

3.21 x 3.21 != 10.3041 is only accurate to 10.30.

correct me if I am wrong, but as I remember it 3.21 x 3.21 is only accurate to
one decimal because the factors are accurate to only 1 place. I am pretty sure
of that but it has been a while since I worried about "precision" and "double
precision" numbers.

Correct.

Later,

Tom
S. Woodstock, CT
----------
"My rod and my reel - they comfort me."

St. Pete, 12 Lb. Test

On Sun, 18 Jan 2004 11:53:25 -0500, Wayne.B
wrote:

The concepts being wrestled with here are "precision" and "accuracy".

Precision implies repeatable results to some number of decimal places
plus or minus an uncertainty factor.

That is true.

Accuracy implies the correct answer in absolute terms.

Accuracy is related to how good (accurate) the data set is. For
example, "accurate within 3 meters" is not an absolute - it could
be dead on, or three meters off. Now if the phrase stated "accurate
to within 2.987654321 =/- .0000000001 meters" - that is precise - you
will always know that you will be within 2.987654321 +/- .0000000001
meters of any mark rather than somewhere within the accuracy range of
0 to 3 meters.

Now I have a headache.

Later,

Tom
S. Woodstock, CT
----------
"My rod and my reel - they comfort me."

St. Pete, 12 Lb. Test

snip
The concepts being wrestled with here are "precision" and "accuracy".

Precision implies repeatable results to some number of decimal places
plus or minus an uncertainty factor.

That is true.

Accuracy implies the correct answer in absolute terms.

Accuracy is related to how good (accurate) the data set is. For
example, "accurate within 3 meters" is not an absolute - it could
be dead on, or three meters off. Now if the phrase stated "accurate
to within 2.987654321 =/- .0000000001 meters" - that is precise - you
will always know that you will be within 2.987654321 +/- .0000000001
meters of any mark rather than somewhere within the accuracy range of
0 to 3 meters.

snip
I work with precision measuring devices and find that these are slippery
concepts for most people. The shoddy day-to-day usage and close relationship
between the two words does not make things any easier.
See:
http://www.ieee-uffc.org/freqcontrol...g/vigaccur.htm
for a nice intuitive explanation of the difference between accuracy and
precision.

Mark Browne

"Mark Browne" wrote in message
news:xcEOb.80651$sv6.188571@attbi_s52...
snip
The concepts being wrestled with here are "precision" and "accuracy".

Precision implies repeatable results to some number of decimal places
plus or minus an uncertainty factor.

That is true.

Accuracy implies the correct answer in absolute terms.

Accuracy is related to how good (accurate) the data set is. For
example, "accurate within 3 meters" is not an absolute - it could
be dead on, or three meters off. Now if the phrase stated "accurate
to within 2.987654321 =/- .0000000001 meters" - that is precise - you
will always know that you will be within 2.987654321 +/- .0000000001
meters of any mark rather than somewhere within the accuracy range of
0 to 3 meters.

snip
I work with precision measuring devices and find that these are slippery
concepts for most people. The shoddy day-to-day usage and close
relationship
between the two words does not make things any easier.
See:
http://www.ieee-uffc.org/freqcontrol...g/vigaccur.htm
for a nice intuitive explanation of the difference between accuracy and
precision.

Mark Browne



Really bad when I make the mistake on an explanation posting. Used to teach
Digital Signal Processing and programming for Texas Instrument fixpoint
DSP's.
Bill

On Sun, 18 Jan 2004 22:58:41 GMT, "Mark Browne"
wrote:

snip
The concepts being wrestled with here are "precision" and "accuracy".

Precision implies repeatable results to some number of decimal places
plus or minus an uncertainty factor.

That is true.

Accuracy implies the correct answer in absolute terms.

Accuracy is related to how good (accurate) the data set is. For
example, "accurate within 3 meters" is not an absolute - it could
be dead on, or three meters off. Now if the phrase stated "accurate
to within 2.987654321 =/- .0000000001 meters" - that is precise - you
will always know that you will be within 2.987654321 +/- .0000000001
meters of any mark rather than somewhere within the accuracy range of
0 to 3 meters.

snip
I work with precision measuring devices and find that these are slippery
concepts for most people. The shoddy day-to-day usage and close relationship
between the two words does not make things any easier.
See:
http://www.ieee-uffc.org/freqcontrol...g/vigaccur.htm
for a nice intuitive explanation of the difference between accuracy and
precision.

That was interesting - I was going to use rifle accuracy as an
example.

Actually, I was bored stiff yesterday and wanted to play with the
concept a little.

Oh well - back to the grind. :)

It's tough being retired.

Later,

Tom
S. Woodstock, CT
----------
"My rod and my reel - they comfort me."

St. Pete, 12 Lb. Test