[Proj] A much better summary of a discussion on this list
Michael Ossipoff
mikeo2106 at msn.com
Thu Aug 16 04:08:42 PDT 2007
Again, Im sorry to post so much, but I havent properly commented on the
bizarre events of the discussion with Daan.
Before you get angry at me for posting this long message of comments on
Daans statements, I want to remind you that, for each of these comments,
there was a posted statement by Daan. Im replying to a huge volume of
attack based on mis-statements, mis-quotes, straw-man tactics, etc. Thats
why this posting is so long.
I didnt start writing to Daan. Daan started writing to me. I didnt start
the discussion with Daan. No one asked him to begin characterizing me or the
quality of my statements.
Its because Daan chose to characterize me, and because his postings
evolved to be more about me than about my topic, that I claim that a more
complete summary of this discussion, with some quotes, is justified.
Obfuscation or successful misrepresentation is possible when the entire
record isnt summarized together, in one posting, as I do here.
Cross-referencing spoils the effect of Dans misquotes, mis-statements,
evasions and straw-man games. As I said before, I claim that I have a right
to answer comments or characterizations about me. Because, this time, this
postings comments will be adequately complete, I promise that this will
_genuinely_ be my last posting here--unless someone else chooses to
perpetuate the discussion by posting more statements to answer.
And I apologize again to the list for the length of this discussion. I dont
want to waste your inbox-space, and this will be my last posting here.
As Ill show here, with quotations, Daans postings in this discussion have,
from the start, consisted of evasions, mis-statements, misquotes, and rather
shameless repetition of unsupported claims that he had already been called
on. And, as is so often resorted to by someone who cant support his claims
on their own merit, Daans posts tend increasingly toward criticism of the
person with whom he wants to disagree
Evasions? Whats the point of evasions in voluntary, unsolicited
opinion-expression? Good question.
I started here merely stating a fault with data maps, and making the
suggestion that maps intended to tell what is where should give the typical
user a way to find out what is where. It seemed a simple, harmless, and
uncontroversial thing to say. More specifically, nearly all map users, when
they want to find or determine a lat/long position, do so by linear
interpolation. Therefore there is good reason for a data map, if it is to be
usable by typical map users, to let positions be accurately found or
measured by linear interpolation. I had no idea what anger I was stirring up
by that claim. I had no intention of getting into a contentious discussion.
So, first, let me quote Daans first comment about my statements:
Daan said:
Easily converting between map coordinates and spherical coordinates is one
reason to choose a projection.
I comment:
Especially if the map is for the purpose of showing where something (species
range, temperature zone, etc) is.
Daan says:
When a mapmaker decides that's the most important reason, the mapmaker does
just what you suggest.
I comment:
No. He doesnt. Thats the first of a series of mis-statements by Daan. Ive
never heard of a mapmaker using a graduated equidistant projection. Ive
never heard of a publisher of a modern-day data map using the equidistant
elliptical (Apianus II). Even an ordinary equidistant cylindrical is quite
rare (unheard of these days?) as a data map.
Daan continues:
Generally the mapmaker decides other factors are more important.
I comment:
There, Daan is merely repeating what Id pointed out. I posted my message
only because generally the mapmaker decides that other factors are more
important. Daans point in repeating me? Who knows? The highest form of
flattery?
I wont quote or comment on Daans other postings line-by-line, as I did
with this one. I wanted to show that Daans first posting in this discussion
sets his tone and his discussion-level and conduct throughout. Ill only
quote the more brazen mis-statements and the ones that he relies on more.
In his next posting, Daan says:
Mike, I'd need to know a little more about what you mean by "data maps".
I comment:
Thats odd, because, even in my first posting, I clarified that I was
referring to spatial distribution maps in atlases. Which part of that
doesnt Daan understand? Later I include nature guidebook species range
maps. Is that part of the evolving positions that so terribly confuses
Daan?
Daan says:
Most maps whose primary purpose is to show spatial distributions are
expected to be equal-area.
I quote this because its the reason why I then suggested the sinusoidal as
a compromise, because its both equal-area and linearly interpolable. Daan
will then say that my addition of the sinusoidal equal-area compromise is an
evolution of positions, and as muddy as it gets. I mention that here to
tell why I quote his mention of equal area.
Daan continues:
Equal-area conflicts with equidistant.
I comment:
Yes, if equidistant requires straight meridians. But not if it just refers
to parallels being equidistantly-spaced on the map. Then the sinusoidal is
equidistant and equal-area. More importantly, the sinusoidal is both equal
area and linearly-interpolable. Later Daan wants to make an issue of the
meaning of equidistant, though it isnt relevant to the value of the
sinusoidal as a compromise between equal area and linear interpolability.
Next, Daan shows us another ridiculous evasion:
In your example of "zones of vegetation", there are the grossly defined
"tropical", "temperate", and "arctic" zones, where latitude is the primary
consideration. In those cases, precise distances mean little and the map's
depiction of parallels is thought to suffice.
I comment:
I said at the outset that I was referring to spatial distribution maps in
atlases. I doubt that a map of Daans three zones can even be found in a
modern atlas. And Ive never found an atlas climate or vegetation map whose
zones were latitude bands. Perhaps Daan is ignorant of the fact that, at a
given latitude, deeply continental climate is entirely different from
coastal climate, and that east coast climate is entirely different from west
coast climate. And that such things as altitude, rain-shadow effects, nearby
ocean currents, and monsoon effects cause climate differences between places
at the same latitude.
But even if atlases had any maps such as Daan describes, it would be a tiny
fraction of an atlass vegetation and climate spatial distribution maps. And
I was talking about spatial distribution maps in general, not just
vegetation maps. This is an example of the old and dishonest straw-man
technique. Why Daan would bother with such techniques and games, I have no
idea.
Daan continues:
If you are referring to ground-cover maps of a continental or global scope,
then I should think an equal-area representation would be paramount.
I comment:
But then, when I later, in reply, suggest the sinusoidal as an equal-area
compromise, Daan calls that a confusing evolution of positions.
Daan continued:
If you are referring to large-scale ground-cover maps
I comment:
Large scale maps in an atlas? As I said, I clarified at the outset that I
was referring to atlas maps. This could be another straw-man example, or an
example of Daans technique of pretending to mis-understand something or
miss something, so that he can evade by arguing with something that wasnt
said.
Daan continued:
, then the precise purpose of the map would strongly influence the choice of
projection. In this last case, is the ease of determining the precise
geographic coordinate of a point more important than accurate distances
measured between any two points on the map? More important than precise
directions anywhere on the map? More important than being able to overlay
and compare against existing printed maps?
I comment:
Id made it abundantly clear that I was talking about maps whose purpose is
to show where various kinds of zones are. During the discussion I repeatedly
pointed out that it would be difficult to find a scenario where someone
needed accurate distances or directions from a bird book or a rainfall
distribution map in an atlas. This was apparently always one of the points
that Daan didnt answer--while he kept on emphasizing the primacy of
accurate distance.
As for overlays, again, I made it clear that I was talking about atlas and
bird book maps, which dont have overlays to lay over USGS maps, etc.
Daan continued:
Your thesis is really about the need for easy conversion from map
coordinates to geographic coordinates.
I comment:
You catch on fast, Daan.
Daan continues:
I haven't got a good sense yet for why that need trumps the others.
I comment:
Well, how about because Daan has never answered my question about why a user
of a bird book or atlas rainfall distribution map would need distances or
directions from that map?
a map that is intended to show where a bird
species is found, or where a certain rainfall zone is, so that you can
determine which zone a particular place is in, or whether a particular bird
can be found in a particular park or county.
In Daans next posting, he says:
Constant scale along parallels is not related to equidistance because
parallels are not great circles. The shortest path between two points on a
parallel is never the parallel itself unless the parallel is the equator.
I comment:
But Id never said otherwise. Another example of Daans constant, persistent
straw-man effort.
Without repeating my answers to Daans other statements in that posting,
Ill merely mention that this is the one where he says:
I can't really get into a whack-a-mole game of responding to each of your
points only to have several more spring up in their places
I comment:
I had not been sending him a barrage of random whack-a-mole points, only to
be replaced by new ones. Rather, Id been merely answering Daans own
statements.
My own points were few and consistent: The fact that a map for showing
where certain zones are is of little use if typical users dont have an
accurate way to find and determine positions on the map; the concession
(after Daan insisted on equal area) that some might want equal area for
certain kinds of mapped data, for which the sinusoidal would then be a good
compromise; and the fact that it would be difficult to come up with a
scenario in which someone needs accurate distances &/or directions from a
bird book range-map or a rainfall distribution map in an atlas.
In Daans next posting there are just a few brief things to mention. Here he
makes an unsupported and unspecified charge:
your analysis of the issues surrounding your thesis seem to evolve as we
talk. These make it hard for me to engage you in conversation.
Later he tells what it is that he claims has evolved. I quote this
because, I quoted him in an earlier posting in which he advocated equal area
for data maps. Below, he faults me for being inconsistent, or evolving
when I mentioned an equal area compromise, in response to his claim that
equal area is needed:
Dan says:
You started out claiming a "graduated equidistant" is the answer. You've now
evolved to an "interrupted sinusoidal". That's about as muddy as it gets.
I comment:
Come again? Whats muddy about offering an equal area compromise when
someone insists that equal area is needed? I mentioned interruption in
connection with a world map, where sinusoidal is used because equal area is
demanded.
In his last posting, Ill just quote one statement:
Balderdash. You made no mention of the utility of equal-area in your
original posting
I comment:
Nor did I advocate the utility of equal-area at any time in the discussion.
I conceded that some might want equal area for some kinds of mapped
information.. I compromised with the desire for it, by suggesting the
sinusoidal as an equal-area compromise.
Daan apparently wanted to play the role of the patient (ersatz?) scientist
doing his best to communicate with someone who wasnt communicating
co-operatively. When the facts dont fit the scenario, thats no problem for
Daan, because Daan doesnt mind mis-representing the facts to fit his
desired role and his chosen scenario.
A few addenda:
1. Earlier I precisely defined the linearly interpolable positions property
(LIPP)
I consider LIPP to be a useful way to say what it says.
But a briefer definition and name are possible. I dont post this in order
to replace LIPP with it. I merely add it as another way to say it:
A projection has the linearity property if, when a map is precisely
constructed on that projection, its possible to divide that map into
regions, throughout each of which the Y co-ordinate on the map varies
linearly with latitude, and its possible to divide that map into regions,
throughout each of which the X co-ordinate on the map varies linearly with
longitude.
[end of linearity property definition]
For practical purposes that definition can be shortened by substituting
its possible to divide the map into regions throughout each of which the
Y co-ordinate on the map varies linearly with latitude and the X co-ordinate
on the map varies linearly with longitude.
[end of briefer linearity2 property definition]
Officially Ill stick with the more general longer first wording. Often I
might use the briefer second wording. Officially, Ill call the second
definition the definition of linearity2.
LIPP and linearity are both worthwhile ways of saying it, with different
emphases in their definition and name.
2. I wouldnt recommend the orthographic elliptical for an atlas or put it
on the wall, because its more a picture than a useful map. And it has no
measurement properties.
3. I dont mean to imply that all maps should have the property that I
advocate for data maps. What Ive said about that applies only to species
range maps in nature guidebooks and spatial distribution maps in atlases.
4. I dont mean to imply that the only maps that should ever be published
are those whose construction can be explained to everyone. Some people might
want the properties of maps that they wouldnt want to hear the construction
explanation of, and wouldnt care about the construction explanation. And
some might care about the construction but also be familiar with it or
willing to study it.
But I do claim that construction explainable to everyone is often an
important and valuable attribute for a map, and one that cartographers dont
appreciate. Some people _would_ prefer a map whose construction can easily
and briefly be defined to them.
Michael Ossipoff
Again, Im sorry to post so much, but I havent properly commented on the
bizarre events of the discussion with Daan.
Before you get angry at me for posting this long message of comments on
Daans statements, I want to remind you that, for each of these comments,
there was a posted statement by Daan. Im replying to a huge volume of
attack based on mis-statements, mis-quotes, straw-man tactics, etc. Thats
why this posting is so long.
I didnt start writing to Daan. Daan started writing to me. I didnt start
the discussion with Daan. No one asked him to begin characterizing me or the
quality of my statements.
Its because Daan chose to characterize me, and because his postings
evolved to be more about me than about my topic, that I claim that a more
complete summary of this discussion, with some quotes, is justified.
Obfuscation or successful misrepresentation is possible when the entire
record isnt summarized together, in one posting, as I do here.
Cross-referencing spoils the effect of Dans misquotes, mis-statements,
evasions and straw-man games. As I said before, I claim that I have a right
to answer comments or characterizations about me. Because, this time, this
postings comments will be adequately complete, I promise that this will
_genuinely_ be my last posting here--unless someone else chooses to
perpetuate the discussion by posting more statements to answer.
And I apologize again to the list for the length of this discussion. I dont
want to waste your inbox-space, and this will be my last posting here.
As Ill show here, with quotations, Daans postings in this discussion have,
from the start, consisted of evasions, mis-statements, misquotes, and rather
shameless repetition of unsupported claims that he had already been called
on. And, as is so often resorted to by someone who cant support his claims
on their own merit, Daans posts tend increasingly toward criticism of the
person with whom he wants to disagree
Evasions? Whats the point of evasions in voluntary, unsolicited
opinion-expression? Good question.
I started here merely stating a fault with data maps, and making the
suggestion that maps intended to tell what is where should give the typical
user a way to find out what is where. It seemed a simple, harmless, and
uncontroversial thing to say. More specifically, nearly all map users, when
they want to find or determine a lat/long position, do so by linear
interpolation. Therefore there is good reason for a data map, if it is to be
usable by typical map users, to let positions be accurately found or
measured by linear interpolation. I had no idea what anger I was stirring up
by that claim. I had no intention of getting into a contentious discussion.
So, first, let me quote Daans first comment about my statements:
Daan said:
Easily converting between map coordinates and spherical coordinates is one
reason to choose a projection.
I comment:
Especially if the map is for the purpose of showing where something (species
range, temperature zone, etc) is.
Daan says:
When a mapmaker decides that's the most important reason, the mapmaker does
just what you suggest.
I comment:
No. He doesnt. Thats the first of a series of mis-statements by Daan. Ive
never heard of a mapmaker using a graduated equidistant projection. Ive
never heard of a publisher of a modern-day data map using the equidistant
elliptical (Apianus II). Even an ordinary equidistant cylindrical is quite
rare (unheard of these days?) as a data map.
Daan continues:
Generally the mapmaker decides other factors are more important.
I comment:
There, Daan is merely repeating what Id pointed out. I posted my message
only because generally the mapmaker decides that other factors are more
important. Daans point in repeating me? Who knows? The highest form of
flattery?
I wont quote or comment on Daans other postings line-by-line, as I did
with this one. I wanted to show that Daans first posting in this discussion
sets his tone and his discussion-level and conduct throughout. Ill only
quote the more brazen mis-statements and the ones that he relies on more.
In his next posting, Daan says:
Mike, I'd need to know a little more about what you mean by "data maps".
I comment:
Thats odd, because, even in my first posting, I clarified that I was
referring to spatial distribution maps in atlases. Which part of that
doesnt Daan understand? Later I include nature guidebook species range
maps. Is that part of the evolving positions that so terribly confuses
Daan?
Daan says:
Most maps whose primary purpose is to show spatial distributions are
expected to be equal-area.
I quote this because its the reason why I then suggested the sinusoidal as
a compromise, because its both equal-area and linearly interpolable. Daan
will then say that my addition of the sinusoidal equal-area compromise is an
evolution of positions, and as muddy as it gets. I mention that here to
tell why I quote his mention of equal area.
Daan continues:
Equal-area conflicts with equidistant.
I comment:
Yes, if equidistant requires straight meridians. But not if it just refers
to parallels being equidistantly-spaced on the map. Then the sinusoidal is
equidistant and equal-area. More importantly, the sinusoidal is both equal
area and linearly-interpolable. Later Daan wants to make an issue of the
meaning of equidistant, though it isnt relevant to the value of the
sinusoidal as a compromise between equal area and linear interpolability.
Next, Daan shows us another ridiculous evasion:
In your example of "zones of vegetation", there are the grossly defined
"tropical", "temperate", and "arctic" zones, where latitude is the primary
consideration. In those cases, precise distances mean little and the map's
depiction of parallels is thought to suffice.
I comment:
I said at the outset that I was referring to spatial distribution maps in
atlases. I doubt that a map of Daans three zones can even be found in a
modern atlas. And Ive never found an atlas climate or vegetation map whose
zones were latitude bands. Perhaps Daan is ignorant of the fact that, at a
given latitude, deeply continental climate is entirely different from
coastal climate, and that east coast climate is entirely different from west
coast climate. And that such things as altitude, rain-shadow effects, nearby
ocean currents, and monsoon effects cause climate differences between places
at the same latitude.
But even if atlases had any maps such as Daan describes, it would be a tiny
fraction of an atlass vegetation and climate spatial distribution maps. And
I was talking about spatial distribution maps in general, not just
vegetation maps. This is an example of the old and dishonest straw-man
technique. Why Daan would bother with such techniques and games, I have no
idea.
Daan continues:
If you are referring to ground-cover maps of a continental or global scope,
then I should think an equal-area representation would be paramount.
I comment:
But then, when I later, in reply, suggest the sinusoidal as an equal-area
compromise, Daan calls that a confusing evolution of positions.
Daan continued:
If you are referring to large-scale ground-cover maps
I comment:
Large scale maps in an atlas? As I said, I clarified at the outset that I
was referring to atlas maps. This could be another straw-man example, or an
example of Daans technique of pretending to mis-understand something or
miss something, so that he can evade by arguing with something that wasnt
said.
Daan continued:
, then the precise purpose of the map would strongly influence the choice of
projection. In this last case, is the ease of determining the precise
geographic coordinate of a point more important than accurate distances
measured between any two points on the map? More important than precise
directions anywhere on the map? More important than being able to overlay
and compare against existing printed maps?
I comment:
Id made it abundantly clear that I was talking about maps whose purpose is
to show where various kinds of zones are. During the discussion I repeatedly
pointed out that it would be difficult to find a scenario where someone
needed accurate distances or directions from a bird book or a rainfall
distribution map in an atlas. This was apparently always one of the points
that Daan didnt answer--while he kept on emphasizing the primacy of
accurate distance.
As for overlays, again, I made it clear that I was talking about atlas and
bird book maps, which dont have overlays to lay over USGS maps, etc.
Daan continued:
Your thesis is really about the need for easy conversion from map
coordinates to geographic coordinates.
I comment:
You catch on fast, Daan.
Daan continues:
I haven't got a good sense yet for why that need trumps the others.
I comment:
Well, how about because Daan has never answered my question about why a user
of a bird book or atlas rainfall distribution map would need distances or
directions from that map?
a map that is intended to show where a bird
species is found, or where a certain rainfall zone is, so that you can
determine which zone a particular place is in, or whether a particular bird
can be found in a particular park or county.
In Daans next posting, he says:
Constant scale along parallels is not related to equidistance because
parallels are not great circles. The shortest path between two points on a
parallel is never the parallel itself unless the parallel is the equator.
I comment:
But Id never said otherwise. Another example of Daans constant, persistent
straw-man effort.
Without repeating my answers to Daans other statements in that posting,
Ill merely mention that this is the one where he says:
I can't really get into a whack-a-mole game of responding to each of your
points only to have several more spring up in their places
I comment:
I had not been sending him a barrage of random whack-a-mole points, only to
be replaced by new ones. Rather, Id been merely answering Daans own
statements.
My own points were few and consistent: The fact that a map for showing
where certain zones are is of little use if typical users dont have an
accurate way to find and determine positions on the map; the concession
(after Daan insisted on equal area) that some might want equal area for
certain kinds of mapped data, for which the sinusoidal would then be a good
compromise; and the fact that it would be difficult to come up with a
scenario in which someone needs accurate distances &/or directions from a
bird book range-map or a rainfall distribution map in an atlas.
In Daans next posting there are just a few brief things to mention. Here he
makes an unsupported and unspecified charge:
your analysis of the issues surrounding your thesis seem to evolve as we
talk. These make it hard for me to engage you in conversation.
Later he tells what it is that he claims has evolved. I quote this
because, I quoted him in an earlier posting in which he advocated equal area
for data maps. Below, he faults me for being inconsistent, or evolving
when I mentioned an equal area compromise, in response to his claim that
equal area is needed:
Dan says:
You started out claiming a "graduated equidistant" is the answer. You've now
evolved to an "interrupted sinusoidal". That's about as muddy as it gets.
I comment:
Come again? Whats muddy about offering an equal area compromise when
someone insists that equal area is needed? I mentioned interruption in
connection with a world map, where sinusoidal is used because equal area is
demanded.
In his last posting, Ill just quote one statement:
Balderdash. You made no mention of the utility of equal-area in your
original posting
I comment:
Nor did I advocate the utility of equal-area at any time in the discussion.
I conceded that some might want equal area for some kinds of mapped
information.. I compromised with the desire for it, by suggesting the
sinusoidal as an equal-area compromise.
Daan apparently wanted to play the role of the patient (ersatz?) scientist
doing his best to communicate with someone who wasnt communicating
co-operatively. When the facts dont fit the scenario, thats no problem for
Daan, because Daan doesnt mind mis-representing the facts to fit his
desired role and his chosen scenario.
A few addenda:
1. Earlier I precisely defined the linearly interpolable positions property
(LIPP)
I consider LIPP to be a useful way to say what it says.
But a briefer definition and name are possible. I dont post this in order
to replace LIPP with it. I merely add it as another way to say it:
A projection has the linearity property if, when a map is precisely
constructed on that projection, its possible to divide that map into
regions, throughout each of which the Y co-ordinate on the map varies
linearly with latitude, and its possible to divide that map into regions,
throughout each of which the X co-ordinate on the map varies linearly with
longitude.
[end of linearity property definition]
For practical purposes that definition can be shortened by substituting
its possible to divide the map into regions throughout each of which the
Y co-ordinate on the map varies linearly with latitude and the X co-ordinate
on the map varies linearly with longitude.
[end of briefer linearity2 property definition]
Officially Ill stick with the more general longer first wording. Often I
might use the briefer second wording. Officially, Ill call the second
definition the definition of linearity2.
LIPP and linearity are both worthwhile ways of saying it, with different
emphases in their definition and name.
2. I wouldnt recommend the orthographic elliptical for an atlas or put it
on the wall, because its more a picture than a useful map. And it has no
measurement properties.
3. I dont mean to imply that all maps should have the property that I
advocate for data maps. What Ive said about that applies only to species
range maps in nature guidebooks and spatial distribution maps in atlases.
4. I dont mean to imply that the only maps that should ever be published
are those whose construction can be explained to everyone. Some people might
want the properties of maps that they wouldnt want to hear the construction
explanation of, and wouldnt care about the construction explanation. And
some might care about the construction but also be familiar with it or
willing to study it.
But I do claim that construction explainable to everyone is often an
important and valuable attribute for a map, and one that cartographers dont
appreciate. Some people _would_ prefer a map whose construction can easily
and briefly be defined to them.
Michael Ossipoff
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