ok mike
no need to respond after all
i can answer my own questions now
as follows
the fact that both geocoords on the plaque end in 0 or 5 means
there is a 96 percent probability that they are actually
demicentisecs & a 4 percent probability that they are normal
millisecs
period
& this is indeed a 24 to 1 shot
which is just another way of saying the same thing
period again
& therefore no new changes are needed
& end of story
--- In
BoundaryPoint@yahoogroups.com, "aletheiak"
<aletheiak@y...> wrote:
> ok good news
> & just the help i needed & sought
>
> therefore please see my further improvements inserted below
>
> --- In BoundaryPoint@yahoogroups.com, Michael Kaufman
> <mikekaufman79@y...> wrote:
> > Not 16:1. You can't do math with odds very well.
>
> ah but thanx to you i think i can now
> provided you can also answer my additional question at the
end
>
> > Think in terms of probabilities. I'm assuming you
> > figured a 1/5 chance for each of the two digits to be
> > either 0 or 5. So you said 4:1 odds on each digit.
> > But you can't simply multiply them. You can however
> > multiply the probabilities together. (1/5) * (1/5) =
> > 1/25. Another way to look at it is there are 4
> > chances out of 100 for a 0 or 5 to come up in each of
> > the two digit slots (0 and 0, 0 and 5, 5 and 0, or 5
> > and 5). 4/100 is again 1/25. So this is the
> > probability you need to know.
> >
> > --- aletheia kallos <aletheiak@y...> wrote:
> >
> > > well doc & dave &al
> > > i think i have finally done it
> > >
> > > extracted the ultimate computational truth out of
> > > bcidwa
> > > thanxxx also to you all
> > >
> > > but it is still in rather long winded format
> > > so please keep bearing with me
> > > & maybe you can help improve it too
> > >
> > >
> > > to begin with
> > > cribbing from the comparatively finer but sketchier
> > > table of geodetic constants at lower right in
> > >
> >
>
http://www.convertit.com/Go?ConvertitReference/AMS55.ASP?Re
> s=150Page=8
> > > i have computed the length of a minute of latitude
> > > at
> > > the 49th parallel as 1853meters plus 508mm
> > >
> > > & borrowing directly from the coarser but busier
> > > table
> > > in
> > > http://home.online.no/~sigurdhu/Grid_1deg.htm
> > > i have it as 1853meters plus 500mm
> > >
> > > so which is truer
> > > & how many digits are reliable in any case
> > >
> > > but no matter
> > > as these are only idle if still interesting
> > > questions
> > > since both produce fully significant centisecs of
> > > 1 point 01351feet
> > > & thats plenty significant
> > >
> > >
> > > also
> > > parenthetically
> > > & only for later use
> > > they produce fully significant millisecs of
> > > zero point 101351 foot
> > >
> > >
> > >
> > > but so anyway for starters
> > > this true centisec length in 6 significant digits
> > > rather than just a plain approximate statute foot is
> > > the true breadth of the swath cut by the ibc
> > > centisec
> > > coord ribbon between monuments 194 & 195
> > >
> > >
> > > a n d
> > >
> > > in
> > >
> >
http://groups.yahoo.com/group/BoundaryPoint/message/14910
> > >
> > > i was wrong to needlessly dumb down the plaque
> > > coords
> > > to the level of the ibc coords
> > >
> > > but by the same token i think it would also be rash
> > > to
> > > trust the millisecs expressed on the plaque as
> > > anything more than actual demicentisecs
> > > since their final significant digits are
> > > suspiciously
> > > 5 & 0 respectively
> > > & together present a 16 to 1 probability that they
> > > are
> > > not significant millisecs at all
> > > but only significant demicentisecs
>
>
> not 16 to 1
> but a 1 in 25 probability
> or actually a 24 to 1 shot
> dont you agree
>
>
> > > for these could easily prove to have been
> > > ambiguously
> > > &or overconfidently stated on the plaque in nad83
> > > & thus could have been overconfidently converted
> > > into
> > > nad27 by me
> > > with 1 full additional significant digit each
> > > as
> > > nlat 48d 59m 57s 357 & wlong 117d 01m 52s 848
> > > when the likelier value ranges 5 full millsecs
> > > between the 355th & 360th millisec actually
> > > of the 58th second of the final minute of the 49th
> > > degree of latitude
> > > in the case of the datum we will need to use here
> > >
> > >
> > > but by taking into account both the major & the
> > > minor
> > > probability & weighting them proportionally
> > > since neither can be dismissed out of hand
> > > & since their relative likelihoods can also be
> > > conveniently & precisely computed
> > > we can indeed now improve the accuracy of the
> > > placement of our intermonumental caus swath across
> > > the
> > > idwa meridian no less than we have improved the
> > > accuracy of the measurement of its width
> > >
> > >
> > > so
> > > recalculating the ratios in
> > >
> >
http://groups.yahoo.com/group/BoundaryPoint/message/14912
> > >
> > > to the limit of their actual applicability
> > > we find that the centisec swath as stated above in
> > > millifeet would be centered on the idwa meridian
> > > exactly 4 point 7379807692 centisecs south of the
> > > latitude of monument 195
> > > which is to say
> > > at precisely nlat 48d59m57s37262019231
> > > on a flat earth
> > >
> > > or comfortably down to the 373rd millisec anyway on
> > > the geoid
> > >
> > >
> > > & therefore
> > > the center of the truest or at least likeliest
> > > available bcidwa centisec swath of width 1 point
> > > 01351
> > > feet
> > > or 12 point 16212 inches
> > > lies between 13 & 18 millisecs north of the 1909
> > > disk
> > > center
> > >
> > > or in better words
> > > between 1 point 317563 & 1 point 824318 feet north
> > > of
> > > it
> > >
> > > or in still easier words to understand
> > > between 15 point 810756 inches north of it
> > > & 21 point 891816 inches north of it
> > >
> > >
> > >
> > >
> > > therefore the better of the 2 best available guesses
> > > for true bcidwa is centered 18 point 851286 inches
> > > north of the 1909 disk center
> > > plus or minus 6 point 08106 inches
> > > & the caus centisec swath therefore most
> > > probabalistically crosses the idwa meridian between
> > > 12
> > > point 77022 & 24 point 93234 inches north of the
> > > 1909
> > > disk center
> > >
> > >
> > >
> > > if however we knew the plaque coords were true
> > > millisecs
> > > an eventuality which is actually a 16 to 1 long shot
>
>
> again
> actually a 24 to 1 shot
> do you agree
>
>
> > > we could then confidently say the swath was centered
> > > more nearly exactly 15 millisecs north of the disk
> > > center rather than ranging so crudely 13 to 18
> > > millisecs north of it
> > >
> > > & in this event the truest available bcidwa would be
> > > centered 18 point 24318 inches north of it
> > > & thus midway between swath edges lying
> > > 12 point 16212 inches north of it
> > > & 24 point 32424 inches north of it
> > >
> > >
> > > so we can congratulate ourselves twice
> > >
> > > once for nailing the major & once for the minor
> > > premise
>
> & again for finally getting the math right
> if indeed we have
>
> > > & for a last hurrah
> > > combining both these premises into one
> > > we get a slightly expanded range
> > > extending a bit more than a full centisec now
> > > between 12 point 16212 inches north of it
> > > & 24 point 93234 inches north of it
> > >
> > > but as for the best guessed single point in that
> > > range
> > > most interestingly
> > > by weighting & hedging the probabilities at 16 to 1
>
> again make that 24 to 1
> yes
>
> > > we get a las vegas betting line & final word at
> > > 18 point 81552 inches north of the 1909 disk center
>
> & so make this 18 point 82696 inches
>
> > >
> > >
> > > thanx for your patience
> > > & please add on or bust anything you can
>
> & thanx for your first rate scrutiny as well
>
>
> but my lingering question is
> in this analysis
> just because a digit comes up 0 or 5
> does that in itself establish that it is therefore only a
> demicentisec rather than a true millisec that only looks like it
> might be a demicentisec
>
> do you see what i mean
>
> or isnt there actually a distinct probability of having a millisec &
> another distinct probability of having a demicentisec in the
case
> of every 0 & 5 that occurs
> as well as the 8 other distinct exclusively millisec probabilities
> in the cases of the remaining 8 digits
>
> so unless you can correct or improve me again
> i would be inclined to consider this overall situation as not just
a
> 2 in 10 chance times another 2 in 10 chance
> but perhaps more like a 2 in 12 chance times a 2 in 12 chance
> or maybe even a 2 in 20 chance times a 2 in 20 chance
> or some other value
> i dont know
> for i dont know how to evaluate the relative likelihood of each of
> these 2 distinctively different types of zeros & fives occurring in
> reality
>
>
> or is all this just a nevada mirage
> with no likelihood at all other than the
> 2 in 10
> times
> 2 in 10
> you have already identified
>
> meaning
> if a digit comes up either 0 or 5 it is a suspected demicentisec
> & if it comes up anything else it is not a suspected
demicentisec
> so we have only either a net 4 in 100 or a net 96 in 100 chance
> for the series of 2 events we are analyzing
> & end of story
>
>
> but in fact which of these is the correct analysis & why