# Best coordinates ever.

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Here is a picture of all of that awesome equipment, ready to go:

If one wants 'the best coordinates ever' that is the equipment required. In place taking readings for 24 hours or so, it is accurate to within a half centimeter.

To claim that one will get the best coordinates ever with a bunch of low end gear is naïve at best.

And, as Markwell, precision is a good thing, but it means nothing without accuracy. The low end equipment may give precision, but it will not give accuracy. Thirty feet should be expected. Anything more 'precise' is completely meaningless.

One laughs, with pathetic humor, at the benchmark log saying: "My GPS said this is thrty feet off. It should be corrected." Guess what. That benchmark is far more acurate and precise than your GPS unit!

So, thank you, OP, for providing the unintended humor.

"The Best Coordinates Ever"?

Isn't that the cache that those six delinquent Herdman kids set out after they heard that geocaching offers snacks?

Considering Groundspeak adds up to 3.5 feet of inaccuracy automatically

Wait, what?

You didn't know that?

If you input N 41 41.7965 W 084 48.3615

GS rounds the last digit to the nearest zero rendering that N 41 41.7970 W 084 48.3620 and drops the zero to display N 41 41.797 W 084 48.362

A difference of roughly 3.7 ft

OK - here we go. The problem is the definitions of accuracy and precision.

Accuracy has to do with whether the number is right or not.

Precision has to do with how many decimal points to which you take the number.

What needs to happen is a balance between the two.

My son was born October 4, 1995 at 12:03 AM CST

He's a teenager

He's fifteen years old

He's 15.8 years old

He's 5780.558 days old.

Each level is more precise. But they are all accurate. How accurate does it need to be?

Depends on who wants to know. Are we...

...going to the movies?

...applying for a learner's permit to drive?

...applying for a job?

...applying for the Boy Scouts?

Let's say applying for the Boy Scouts. "Teenager" isn't the best answer because that could be anywhere from 13 to 19 - and those are big swings could make him ineligible (once you turn 18, you can't be in Boy Scouts, but you can be a Venture Scout). Most of the time, even on an official application of sorts, knowing that he's 15.8 years old is too precise, but it's nice to know that he's closer to 16 than 15. That would make a difference in applying for a job or a learner's permit.

So how precise should numbers go? That's where significant digits come in: numbers for which the precision gives you useful information. Your example of the different between N 41 41.7965 W 084 48.3615 and N 41 41.7970 W 084 48.3620 shows a difference of 3.795 feet *. The store-bought GPS units are only accurate to about 30 feet. The rounding of the digits is not significant enough to give you a better location. If it were, the GPS companies would allow you to enter seven or even eight digits beyond the numbers you see on Geocaching.com. Changing the coordinates on your GPS from N 41 41.7965 W 084 48.3615 to N 41 41.7970 W 084 48.3620 will not give you a better location for which to search for the cache because the unit isn't that accurate.

So Groundspeak is not "adds up to 3.5 feet of inaccuracy automatically". They are giving you a number that is precise enough to be accurate.

*Interesting little side-note. Your post said "A difference of roughly 3.7 ft". The math comes out to 3.795 feet. If that number were rounded correctly, it would be 3.8 feet. That's because just looking at the number in the tenths position is not sufficient to round. You need to look at the number in the hundredths position. In other words, your supposition of "roughly 3.7 feet" was not accurate, because you didn't look at a precise enough number. Had you said "4 feet" you would have been accurate, and probably precise enough to make your point, which of course was inaccurate.

ACCURATE

1. free from error

2. conforming exactly to truth or to a standard : exact

That is a precise definition.

PRECISE

1. exactly or sharply defined or stated

2. minutely exact

A very accurate definition.

I wonder why accurate is so precise and precise is so accurate. OH! They are the same thing.

Claiming a cache located at N XX XX.XX80 W XXX XX.XX90 when it is at N XX XX.XX76 W XXX XX.XX85 is not precise, accurate or exact.

I guess you inability to cause the world to conform to you inaccurate definitions invalidates your argument.

And the fact that I said roughly means I was attempting to make a ballpark estimate and the fact that I was not trying to be exacting does not invalidate a point considering that that post had no point to make.

What GPS do you use that has that much precision? Every one I've ever used only goes to the thousanths. Any rounding is done by the GPS itself.

An unlocked Mio Digiwalker running Beeline GPS.

We have

1 Ipod touch

1 Android

1 Windows Phone 7

1 Magellan Explorist GC

1 Iphone

1 Cobra GPS 1000

Well, this should at least prove entertaining.

Two low end handhelds, three phones and an MP3 player...

If your objective is to create consternation, you'll do fine.

If you want accurate coords, why not add at least one reasonably accurate GPS receiver?

Actually though, I have the Explorist GC and find it to be pretty accurate.

The GPSr chip is the same as in all Magellan units, I believe. The difference between models is more in the maps and software.

I would love to see sometime an experiment where a lot of people place various brand consumer GPS units on a particular immovable spot and write down the coordinates, just to see how far off they are from each other. Come to think of it, I am going to a EVENT this evening. Maybe I will try to get some people to try it.

We have an annual GIS day in our library and the past couple of years there was a session on Geocaching. There were a few temporary geocaches hidden and the participants were split up into groups to to find. They were also told to go to a specific location (the gate at the entrance of a nearby garden) and told to capture a waypoint. After they all came back inside the waypoints were entered on a mapping program (might have been Mapsource). The results were all over the place with some of the waypoints over 80 feet from others. They were all using identical model GPS devices.

As I see it, having multiple GPS devices isn't likely going to produce the "best coordinates ever". From the list provided the Magellan might be the most accurate. Suppose it's 10 feet off the coordinates obtained with a professional quality survey GPS, if the rest of them are further way, averaging the coordinates is going to produce coordinates further away than if you had just used the Magellan.

We all admire your desire to produce good co-ordinates. This is something every Geocache hider should strive for.

In the final analysis, however, having co-ordinates for your cache that are better than those who seek it are likely to be able to obtain is an exercise in futility.

(Not that I even remotely believe the described method would be helpful/successful.)

So far the best coords I've encountered where on a cache here in town placed by someone with a Garmin Legend. I 'zeroed out', set myGPS down, spent ages looking for the darn cache. It was directly under my GPS!

Let me guess, it was well camo'd?

It's definately commendable to make an effort to provide accurate coordinates. I've found a descriptive hint is also worth it's weight in gold, in case there is lots of tree cover or the satellites are in weird alignment at the time the person is looking for the cache.

So far the best coords I've encountered where on a cache here in town placed by someone with a Garmin Legend. I 'zeroed out', set myGPS down, spent ages looking for the darn cache. It was directly under my GPS!

Let me guess, it was well camo'd?

Actually, not all that camo'ed. The person who spotted it was sitting down about 10 feet away, still a very decent job of camo.

I wonder why accurate is so precise and precise is so accurate. OH! They are the same thing. Claiming a cache located at N XX XX.XX80 W XXX XX.XX90 when it is at N XX XX.XX76 W XXX XX.XX85 is not precise, accurate or exact.

Yep. Ya got me. We should be entering in 8 digits beyond the decimal points in decimal degrees. You do realize that your GPS will calculate positions that far out. I wonder why they don't display them.

Rule of thumb: when something says "best ... ever", it isn't.

Claiming a cache located at N XX XX.XX80 W XXX XX.XX90 when it is at N XX XX.XX76 W XXX XX.XX85 is not precise, accurate or exact.

I guess you inability to cause the world to conform to you inaccurate definitions invalidates your argument.

And the fact that I said roughly means I was attempting to make a ballpark estimate and the fact that I was not trying to be exacting does not invalidate a point considering that that post had no point to make.

Just because you claim to have
An unlocked Mio Digiwalker running Beeline GPS.
that will record coordinates out to those extra decimal points doesn't mean that's useful. Your GPS only able to get you within a margin of error. Most people throw around plus or minus 15 feet in optimum conditions. Let's say, for the sake of the argument, that your GPS is three times more accurate than any other GPS, giving us plus or minus 5 feet. Yeah, that extra digit (3.8 feet!) will be really handy! Not...

Insisting on needing that many digits is kinda like asking a blind man for a measurement in inches when all he's got is a ruler marked out in feet. He can make a guess, but that's all it is.

Hope you didn't waste too much time on your little project. . .

Edit: All this aside, unless you and your super-accurate GPS (from a company I never heard of; can it really be that good if it hasn't caught on with cachers?) are the silent partners in the OP's little endeavor, using the described devices is a bit like handing a room full of blind men stcks that are about a foot long and asking them to measure something in inches.

Edited by Too Tall John

Given a set of instruments measuring something the result is no more accurate than the least accurate instrument in the group. Adding other instruments still leaves the error probability the same.

Secondly if the placer is using something that has an error rate of lets say 15'then trying to find it worth a more accurate had no effect

Edited by Walts Hunting

I bet the op and his buddies are giggling like school girls watching y'all fight over accuracy vs precision and commercial grade vs consumer GPS.

Considering Groundspeak adds up to 3.5 feet of inaccuracy automatically

Wait, what?

You didn't know that?

If you input N 41 41.7965 W 084 48.3615

GS rounds the last digit to the nearest zero rendering that N 41 41.7970 W 084 48.3620 and drops the zero to display N 41 41.797 W 084 48.362

A difference of roughly 3.7 ft

OK - here we go. The problem is the definitions of accuracy and precision.

Accuracy has to do with whether the number is right or not.

Precision has to do with how many decimal points to which you take the number.

What needs to happen is a balance between the two.

My son was born October 4, 1995 at 12:03 AM CST

He's a teenager

He's fifteen years old

He's 15.8 years old

He's 5780.558 days old.

Each level is more precise. But they are all accurate. How accurate does it need to be?

Depends on who wants to know. Are we...

...going to the movies?

...applying for a learner's permit to drive?

...applying for a job?

...applying for the Boy Scouts?

Let's say applying for the Boy Scouts. "Teenager" isn't the best answer because that could be anywhere from 13 to 19 - and those are big swings could make him ineligible (once you turn 18, you can't be in Boy Scouts, but you can be a Venture Scout). Most of the time, even on an official application of sorts, knowing that he's 15.8 years old is too precise, but it's nice to know that he's closer to 16 than 15. That would make a difference in applying for a job or a learner's permit.

So how precise should numbers go? That's where significant digits come in: numbers for which the precision gives you useful information. Your example of the different between N 41 41.7965 W 084 48.3615 and N 41 41.7970 W 084 48.3620 shows a difference of 3.795 feet *. The store-bought GPS units are only accurate to about 30 feet. The rounding of the digits is not significant enough to give you a better location. If it were, the GPS companies would allow you to enter seven or even eight digits beyond the numbers you see on Geocaching.com. Changing the coordinates on your GPS from N 41 41.7965 W 084 48.3615 to N 41 41.7970 W 084 48.3620 will not give you a better location for which to search for the cache because the unit isn't that accurate.

So Groundspeak is not "adds up to 3.5 feet of inaccuracy automatically". They are giving you a number that is precise enough to be accurate.

*Interesting little side-note. Your post said "A difference of roughly 3.7 ft". The math comes out to 3.795 feet. If that number were rounded correctly, it would be 3.8 feet. That's because just looking at the number in the tenths position is not sufficient to round. You need to look at the number in the hundredths position. In other words, your supposition of "roughly 3.7 feet" was not accurate, because you didn't look at a precise enough number. Had you said "4 feet" you would have been accurate, and probably precise enough to make your point, which of course was inaccurate.

ACCURATE

1. free from error

2. conforming exactly to truth or to a standard : exact

That is a precise definition.

PRECISE

1. exactly or sharply defined or stated

2. minutely exact

A very accurate definition.

I wonder why accurate is so precise and precise is so accurate. OH! They are the same thing.

Claiming a cache located at N XX XX.XX80 W XXX XX.XX90 when it is at N XX XX.XX76 W XXX XX.XX85 is not precise, accurate or exact.

I guess you inability to cause the world to conform to you inaccurate definitions invalidates your argument.

And the fact that I said roughly means I was attempting to make a ballpark estimate and the fact that I was not trying to be exacting does not invalidate a point considering that that post had no point to make.

Actually, I was taught pretty much what Markwell says, though a more precise word for what he calls precision is resolution and a more accurate term for what he calls accuracy is degree of error.

A more accurate comparison of precision and accuracy is shown here:

Accuracy is the degree of closeness of a measurement is to the true (or reference) value. Precision is the repeatability of the measurement or the degree to which repeated measurements change.

In Markwell's example, if your measuring device only shows three decimal places of minutes, your may have many measurements that show the same coordinates. But the precision is only .001 minutes because your device can't resolve any smaller amount. If your GPS shows four decimal places of a minute, then you might see differences in the last digit but the range might still be less that .001 minutes. You then have a more precise measurement. But the measurement isn't any more or less accurate.

Claiming a cache located at N XX XX.XX80 W XXX XX.XX90 when it is at N XX XX.XX76 W XXX XX.XX85 is not precise, accurate or exact.

I guess you inability to cause the world to conform to you inaccurate definitions invalidates your argument.

And the fact that I said roughly means I was attempting to make a ballpark estimate and the fact that I was not trying to be exacting does not invalidate a point considering that that post had no point to make.

Just because you claim to have
An unlocked Mio Digiwalker running Beeline GPS.
that will record coordinates out to those extra decimal points doesn't mean that's useful. Your GPS only able to get you within a margin of error. Most people throw around plus or minus 15 feet in optimum conditions. Let's say, for the sake of the argument, that your GPS is three times more accurate than any other GPS, giving us plus or minus 5 feet. Yeah, that extra digit (3.8 feet!) will be really handy! Not...

Insisting on needing that many digits is kinda like asking a blind man for a measurement in inches when all he's got is a ruler marked out in feet. He can make a guess, but that's all it is.

Hope you didn't waste too much time on your little project. . .

Edit: All this aside, unless you and your super-accurate GPS (from a company I never heard of; can it really be that good if it hasn't caught on with cachers?) are the silent partners in the OP's little endeavor, using the described devices is a bit like handing a room full of blind men stcks that are about a foot long and asking them to measure something in inches.

Not only not invalidating my original point but putting words into metaphorical mouth.

I've not claimed that GS should go out an additional point. How much server space and bandwidth would be unnecessarily wasted?

I never claimed that it would be particularly useful either.

1. Pointless to try to get super accurate cords when GS can and does change them if you supply deeper than three decimal points.

2. Changing 1 digit in a coord set does not result in the same location.

1 can be arguable but 2 can not, so why do people want to argue 2 in an attempt to invalidate 1?

Where is the logic in that?

Now to strengthen my original point. You can use a surveyor GPS, double check using a high grade marine beacon location and then triple checking by going to a state meridian and measure the exact bearing and every millimeter between its center and the caches center and the coords you supply would still be pointless in their accuracy. 1 day later I wouldn't be able to put your GPS back into position unless I could find dimples made by the legs, and even then the coordinate readout would be different. May only be different by as little as 1/100th" but it would be different. Now give me those same coords by way of a cache page on GC.com, oh wait, you cant. So I input the cache page coords into my Mio and go stand at GZ and 30-60 seconds later I'm going to GZ at a different location repeat repeat repeat. Chances are very low that most of our receivers will not say GZ is at true GZ.

Horseshoes and hand grenades, maybe once most of us are complaining that out GPSRs are inaccurate by 6" will precise/accurate/exacting coords become relevant. I'll bet someone will start complaining that elevation isn't supplied. Heck I bet someone has.

Not only not invalidating my original point but putting words into metaphorical mouth.

I've not claimed that GS should go out an additional point. How much server space and bandwidth would be unnecessarily wasted?

I never claimed that it would be particularly useful either.

1. Pointless to try to get super accurate cords when GS can and does change them if you supply deeper than three decimal points.

2. Changing 1 digit in a coord set does not result in the same location.

1 can be arguable but 2 can not, so why do people want to argue 2 in an attempt to invalidate 1?

Where is the logic in that?

Reading your first posts to this thread, they read like you were demanding more accurate coordinates. If you were really trying to make the points you claim, do you mind showing us where you made them? Also, could you show me where someone has tried to argue your second point?
Considering Groundspeak adds up to 3.5 feet of inaccuracy automatically there is the possibility that they could (yet doubtful) eventually acquire extremely accurate coords but if they do then chances are GS wont be displaying them to us.
ACCURATE

1. free from error

2. conforming exactly to truth or to a standard : exact

That is a precise definition.

PRECISE

1. exactly or sharply defined or stated

2. minutely exact

A very accurate definition.

I wonder why accurate is so precise and precise is so accurate. OH! They are the same thing.

Claiming a cache located at N XX XX.XX80 W XXX XX.XX90 when it is at N XX XX.XX76 W XXX XX.XX85 is not precise, accurate or exact.

I guess you inability to cause the world to conform to you inaccurate definitions invalidates your argument.

And the fact that I said roughly means I was attempting to make a ballpark estimate and the fact that I was not trying to be exacting does not invalidate a point considering that that post had no point to make.

Edit: Ok, so I highlighted your point #2. Read it again, though. Arguing that a difference of 10,000ths of a degree isn't accurate is an unreasonable claim when your measuring device is inherently unable to make a measurement to that degree(No pun intended) of accuracy. Edited by Too Tall John

Let's introduce the concept of significant digits. The idea is when you take a measurement your device has a certain precision and accuracy. Someone else taking a measurement also had a certain precision and accuracy which may be different than your measurement.

1. It makes no sense for you to use more significant digits than the precision of your device. If you can't measure repeatably to less than .001 minutes than any extra digits you give are meaningless.

2. If you are giving your number to someone else, it makes no sense for them to use more digits than the precision and accuracy of their device. No matter what they do, these extra digits are beyond the capabilities they have to measure.

Geocaching.com does not know the accuracy or precision of either the finder's or hider's GPS. They know that typically the best accuracy for a hand held unit in geocaching is about 10 ft. Sure the hider could use a surveyor grade unit with centimeter accuracy, but nobody is going to look for a cache with one of these units (which require obtaining a reading in one location over an extended period of time). Given this more digits in the listed coordinates are meaningless.

1. Pointless to try to get super accurate cords when GS can and does change them if you supply deeper than three decimal points.

This confuses accuracy with precision. GS is using only 3 decimal digit because given the accuracy and precision of hand held units the additional digits are not significant.

2. Changing 1 digit in a coord set does not result in the same location.

It's true that .0192 doesn't equal .0190. But when you give a measurement you are really saying that the actual value falls in some range. Significant digits are used a shorthand to show the approximate range. If you write .019 you are saying that the actual measurement falls between .0185 and .0195. When you add a significant digit (e.g. .0192) you are saying the actual measurement is between 0.1915 and 0.1925. When GS drops a significant digit they arent saying the actual location is different. What they say is that while the hider may have had a unit that can more precisely say what the coordinates are, most finders will only be able to determine to .001 minutes (if even that much). Droping the digit does not change the actual location, it only implies a bigger range. In addition, if the original measure is inaccurate it doesn't matter how precise it is.

Edited by tozainamboku

What really diferentiates the pro grade from the consumer grade? Is it just the accuracy of the internal clock? I'm pretty sure i remember that a big factor in an accurate reading, short of having a good signal from all 8-12 sats, is having a very accurate clock. Not to mention the ability to run the calculation rather fast.

Can't say that I know exactly what the difference are between consumer-grade, professional-grade or military-grade (aside from cost of the items -- BIG difference, there).

I am pretty sure, however, that a smart phone GPS chip won't guide a Tomahawk missile through a particular window launched from 400 miles away, nor do many surveyors use a hand-held (as we know it) to define borders or property lines.

I don't pretend to know, either, but this website author at least sounds like he knows what he's talking about: http://www.forestpal.com/GPS.html

I wonder when he wrote that.

It's copyrighted 2007-2011 but it says that there are only 2 WAAS satellites... wait, there are currently only two or three. Looked it up.

really great page on WAAS

But he doesn't say a word about ground based WAAS units.

Anyway, how can you trust someone who puts their GPS on top of their hat? How ya supposed to read it???

(he does sound knowledgeable)

But he doesn't say a word about ground based WAAS units.

Are you talking about the ground reference stations? Those only indirectly contribute to the WAAS functionality. They dictate what's being broadcast over the WAAS birds, but they don't broadcast anything themselves (not to GPS units, anyway).

Let's introduce the concept of significant digits. The idea is when you take a measurement your device has a certain precision and accuracy.

Re-introduce...

So how precise should numbers go? That's where significant digits come in: numbers for which the precision gives you useful information.

Puritans. Numerical, mathematical puritans.

There, I said it.

But he doesn't say a word about ground based WAAS units.

Are you talking about the ground reference stations? Those only indirectly contribute to the WAAS functionality. They dictate what's being broadcast over the WAAS birds, but they don't broadcast anything themselves (not to GPS units, anyway).

I was under the impression that they did, but now reading over it more carefully, it seems that they just increase the accuracy of what is coming from the satellite.

thank you for that correction.

Considering Groundspeak adds up to 3.5 feet of inaccuracy automatically

Wait, what?

It's the resolution of the coordinates that are on GC.com

Rule of thumb: when something says "best ... ever", it isn't.

That's a magor good statement.

Rule of thumb: when something says "best ... ever", it isn't.

That's a magor good statement.

That must be why we saw so many advertisements in Europe listing different products as "PROBABLY the best..." whatever.

Considering Groundspeak adds up to 3.5 feet of inaccuracy automatically

Wait, what?

It's the resolution of the coordinates that are on GC.com

But what is the resolution of this thread going to be?

do some of you people collect points for being rude?

even if you have a valid point, stating it rudely gets you no where.

good grief.

I have to be honest, I've seen some rude posts on this forum (and I think some regular posters know that I've made this known ) in general but not at all in this thread. The person using these devices definitely won't come up with the "Best coordinates ever." I'm not knocking them for the devices they use because I myself use two of them and they aren't the greatest. I think everyone here is just offering sound advice.

Now the OP(s) have had time to get their "best coordinates ever"....

What are the results?

Here's an interesting little article on the accuracy of Smartphone GPSrs: http://mashable.com/2011/03/09/smartphone-gps-accuracy/

In all fairness, most people do not leave the GPS on they're phone turned on when they're not using it. I would care to bet that the majority of the inaccurate positions obtained in the article were probably based on the cell network, which doesn't come close to the performance of the phone with GPS enabled.

Agreed. That article is writen by someone who does not understand the subject matter. Cell network triangulation is not accurate at all, so why did that supprise the author. This has nothing to do with GPS. The GPS chipset in most cell phones is failrly good. Some are exelent.

Back to the OP, saying a Droid and a WP7, does not really give anyone any information on the GPS. You need to tell the readers what model you are using. Unlike iPhone, most mobile OSs have many (100s) of makes and models using the OS. Each one will have different GPS accuracy.

So far the best coords I've encountered where on a cache here in town placed by someone with a Garmin Legend. I 'zeroed out', set myGPS down, spent ages looking for the darn cache. It was directly under my GPS!

Been there, signed the log.

Here's an interesting little article on the accuracy of Smartphone GPSrs: http://mashable.com/...e-gps-accuracy/

In all fairness, most people do not leave the GPS on they're phone turned on when they're not using it. I would care to bet that the majority of the inaccurate positions obtained in the article were probably based on the cell network, which doesn't come close to the performance of the phone with GPS enabled.

Agreed. That article is writen by someone who does not understand the subject matter. Cell network triangulation is not accurate at all, so why did that supprise the author. This has nothing to do with GPS. The GPS chipset in most cell phones is failrly good. Some are exelent.

Back to the OP, saying a Droid and a WP7, does not really give anyone any information on the GPS. You need to tell the readers what model you are using. Unlike iPhone, most mobile OSs have many (100s) of makes and models using the OS. Each one will have different GPS accuracy.

If they are using triangulation, I agree. But the article does not say that. It claims to be referring to the GPS data.

... I'll bet someone will start complaining that elevation isn't supplied. Heck I bet someone has.

Someone has. I remember a thread about it a while back. Would be nice info in the mountains...

Here's an interesting little article on the accuracy of Smartphone GPSrs: http://mashable.com/...e-gps-accuracy/

In all fairness, most people do not leave the GPS on they're phone turned on when they're not using it. I would care to bet that the majority of the inaccurate positions obtained in the article were probably based on the cell network, which doesn't come close to the performance of the phone with GPS enabled.

Agreed. That article is writen by someone who does not understand the subject matter. Cell network triangulation is not accurate at all, so why did that supprise the author. This has nothing to do with GPS. The GPS chipset in most cell phones is failrly good. Some are exelent.

Back to the OP, saying a Droid and a WP7, does not really give anyone any information on the GPS. You need to tell the readers what model you are using. Unlike iPhone, most mobile OSs have many (100s) of makes and models using the OS. Each one will have different GPS accuracy.

If they are using triangulation, I agree. But the article does not say that. It claims to be referring to the GPS data.

It does sound like the author simply does not understand the subject matter. The article says it "tracks where user’s phones say they are when they enter Shopkick-enabled locations". If the GPS is turned off, it is very likely the location is not very accurate. They are assuming that these results are coming from the GPS, where in reality, that is probably not the case. From personal experience, my smart phone has been just as accurate as my Garmin.

Here's an interesting little article on the accuracy of Smartphone GPSrs: http://mashable.com/...e-gps-accuracy/

In all fairness, most people do not leave the GPS on they're phone turned on when they're not using it. I would care to bet that the majority of the inaccurate positions obtained in the article were probably based on the cell network, which doesn't come close to the performance of the phone with GPS enabled.

Agreed. That article is writen by someone who does not understand the subject matter. Cell network triangulation is not accurate at all, so why did that supprise the author. This has nothing to do with GPS. The GPS chipset in most cell phones is failrly good. Some are exelent.

Back to the OP, saying a Droid and a WP7, does not really give anyone any information on the GPS. You need to tell the readers what model you are using. Unlike iPhone, most mobile OSs have many (100s) of makes and models using the OS. Each one will have different GPS accuracy.

If they are using triangulation, I agree. But the article does not say that. It claims to be referring to the GPS data.

I guess that would depend on how long the app has been running before the measurements was taken.

I know that alot of peoples complaints about the official geocaching.com app for smartphones' accuarcy is because they are not letting it get a GPS lock. Smartphone useres are not always the most patient people...

Here's an interesting little article on the accuracy of Smartphone GPSrs: http://mashable.com/...e-gps-accuracy/

In all fairness, most people do not leave the GPS on they're phone turned on when they're not using it. I would care to bet that the majority of the inaccurate positions obtained in the article were probably based on the cell network, which doesn't come close to the performance of the phone with GPS enabled.

Agreed. That article is writen by someone who does not understand the subject matter. Cell network triangulation is not accurate at all, so why did that supprise the author. This has nothing to do with GPS. The GPS chipset in most cell phones is failrly good. Some are exelent.

Back to the OP, saying a Droid and a WP7, does not really give anyone any information on the GPS. You need to tell the readers what model you are using. Unlike iPhone, most mobile OSs have many (100s) of makes and models using the OS. Each one will have different GPS accuracy.

If they are using triangulation, I agree. But the article does not say that. It claims to be referring to the GPS data.

Whether it was GPS or A-GPS using cell tower triangulation, I think they are showing the accuracy indoors (Shopkick enabled locations). We all should know that GPS accuracy indoors is not very good, if you can get GPS signals at all. The cell phones are either giving bad GPS indoor readings, or if they can't get GPS reception are falling back to cell tower triangulation.

Bah! GPS'rs are for girly men!

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