The biggest surprise for me was the high performance of some of the implementations of functional programming languages, even in cases where the particular languages aren't generally known for being implementable in a very efficient way. Two of the best-performing languages are stalin (an implementation of scheme/lisp) and mlton (an implementation of ml).
You should not draw too many conclusions about the results of those two without taking into account the fact that both are whole-program optimizing compilers. Those two systems just do not support separate compilation of individual source files; if you change one line of one file in your program, every file must be recompiled.
This type of compiler has a performance advantage over the more common separate compilation systems, simply because it can inline anything anywhere, and thus optimize far more aggressively. But it's next to useless for developing large software systems, and thus mostly really useful only for writing smallish programs, in very high-level style, that perform some really expensive computations really fast.
It's not quite as blatant as most people are assuming from the one sentence at the end. However, she clearly pits a "Latina woman" against a "white male." That's a very interesting choice. To me, it demonstrates that she has a bit of a bone to pick with "white males." Why couldn't she have chosen, I dunno, an female Arab and a male Indian? Why did she choose her race/gender and the white male.
Because she's talking about the SCOTUS' actual record in deciding cases about gender and race issues when the court was all white male. She's not talking about hypotheticals, she's talking about history. It's right there in the next paragraph:
"Let us not forget that wise men like Oliver Wendell Holmes and Justice Cardozo voted on cases which upheld both sex and race discrimination in our society. Until 1972, no Supreme Court case ever upheld the claim of a woman in a gender discrimination case."
Secondly, she seems to think that "inherent physiological or cultural differences" come to play in decisions.
Um, no, you're reading that completely backwards. I'll quote that bit again:
"Whether born from experience or inherent physiological or cultural differences, a possibility I abhor less or discount less than my colleague Judge Cedarbaum, our gender and national origins may and will make a difference in our judging."
The key word there is "whether." That sentence is not endorsing either inherent physiological or cultural differences"; it's disclaiming the assumption of either, for the sake of the point that she's making.
Garbage collection is usually faster than manual allocation -- see Urban Performance Legends, Revisited
Not so fast. It is certainly true that a stop-and-copy algorithm has lower algorithmic time complexity than manual memory management--but it uses more memory, in more than one sense: (a) copying from the old heap to the new heap requires that a new heap be allocated; (b) doing a collection requires touching a lot of memory pages which would otherwise not be touched often, which increases the size of the program's memory working set, limiting the virtual memory manager's ability to manage system memory.
Garbage collection allows objects to be compacted in memory, which increases locality and hence performance greatly.
This is extremely tricky, because again, collection touches memory pages that the program wouldn't touch otherwise, which can offset the benefit from compacting.
There's a more fundamental point to be made here. The idea that the law can be applied "objectively," according to its "plain meaning," assumes that there is such a thing as the "plain meaning" of a text. You bring up the point that a text can be written in a confusing or unclear manner, but that point can be driven a lot further: there is no way to write a text so that it carries its meaning intrinsically within it. Text is something that's used by people; without people who read it and appeal to it to justify concrete choices, text is just stains on paper.
What Judge Sotomayor is saying there is that what the law achieves is not an "objective stance," but rather a compromise between a "series of perspectives." Another way of putting this is that the point of the law is not to state truths, but rather, to resolve disputes between people, by appealing to disinterested third parties (judges, the elders of a neighboring clan, etc.) to decide the issue. But this disinterest is imperfect, because of the third parties' biases and sympathies.
Larry Summers was driven from polite society for a couple of years for the crime of asking whether it was desirable to broach the subject of whether there were basic differences between men and women.
Yeah. The poor man is now relegated to Director of the White House's National Economic Council for President Barack Obama. Horrible fate.
Please explain, in scientific terms, the advantage of a larger sensor. For the purposes of this explanation, do not assume that a larger sensor has more pixels. The lens size is important (larger == better), and the number of pixels is important, but I suspect that packing those pixels into a smaller size will improve picture quality.
I think what you're asking me to do is, in practice, quite flawed. The whole point of having a 4x5" sensor would be to have a hell of a lot more pixels than existing camera sensors. Assuming equivalent pixel densities, this would be 6x as many pixels as a 56x36mm medium format sensor, 14x as many pixels as full-frame 35mm sensors, and 33x times as many pixels as APS-C sized sensors. Compared to a Phase One 40MP 56x36mm sensor, an equivalent 4x5" sensor would have 234 megapixels.
Think of it this way: in the world of film, the advantage of large format over small format comes down to a very simple factor: for a given print size, large format film needs a lot less enlargement. An 8x10" print from 35mm film is an 8.5x linear enlargement; in terms of area, it's 71.7x. The same print from 4x5" film is a 2x linear enlargement. That means finer grain and better tonality.
This logic, however, doesn't translate to digital if you keep the number of pixels constant, because the pixel count puts a hard upper boundary on the resolution of the prints you wish to make. An 8x10" print from a 39 megapixel 4x5" sensor is not going to have more resolution than one from a 39MP 56x36mm one. It may (perhaps!) have better color and less noise, but if that's all you were after, you wouldn't make a sensor with 6x the area!
So yeah, it's fair to say that I implicitly assumed that a 4x5" digital sensor would have more pixels.
The bigger the sensor, the more light that hits it.
Err, no! The amount of light that enters the camera is determined by the size of the lens and is unrelated to the size of the sensor.
Compared to a smaller sensor, the larger sensor requires a larger lens to produce the same field of view. So while the amount of light that enters the camera is determined by the size of the lens, in practice the size of the lens is related to the size of the sensor.
Digital backs for 4"X5" cameras are common, but they shave a bit off the edges. A quick search showed 3"x4" with well over 3000dpi is not uncommon.
Double-check that those are 3"x4" sensors, and not scanning backs. Scanning backs are, basically, putting a scanner on the back of a camera, so you can guess how slow those operate. (Not to mention you need controlled lighting and a still scene; i.e., good for product photography in the studio, not so good for landscapes, awful for people.)
Polaroids can still be useful for previewing exposures in large-format photography, which is still a film world. They simply don't make 4x5" digital sensors, period.
Using a digital camera to take a test shot can be useful in the same situation, but that means using a separate camera, from a slightly different angle, potentially different field of view, etc.
Reason being is that C is the closest high level language to how a processor actually operates.
Once you get things like branch prediction, speculative execution and pipelining into the picture, no, C isn't really any closer to how the processors operate. Making efficient use of a modern CPU involves detail at a much, much lower level than C exposes.
The performance killer for high-level languages isn't really the abstraction away from the machine instruction set; it's garbage collection. And even then, it's mostly because GC tends not to play well with memory caches and virtual memory; a simple stop-and-copy garbage collector is actually algorithmically more efficient than malloc/free, but absolutely atrocious with caches and VM.
But there is law that specifies when you must obey the commands of a police officer, and those laws are constitutional. For example, there exist constitutionally valid laws that prohibit you from using lethal force to resist an arrest by a police officer who's identified himself to you. Those laws remain applicable even if the police are arresting you for violating an unconstitutional law.
The principle stated earlier in this thread very much applies here: it's the courts decide whether a law is constitutional, not you, period.
The article is misleading. I mean, read the thing, and note the fact that it's pirate radio operators (people who are operating powerful, unlicensed transmitters) putting words into the mouth of the FCC. Ask yourself: why would a bunch of pirate radio operators want to portray the FCC as a Gestapo-like agency?
Where is the slippery slope? That the FCC might chose to interpret a 1934 law in a way that obviously contradicts the 4th Amendment? Here's the protection against that: it obviously contradicts the 4th Amendment.
Um, take this scenario: the FCC has evidence that you're operating an unlicensed radio station at your home. They come to your home, knock on your door, and ask to inspect the equipment. You refuse to allow them to enter. At that point, they leave, and when they get back to the office, they fine you for $7,000 dollars.
The law in question gives the FCC the authority to do that. How was the 4th Amendment violated here?
There's another extremely important thing that we should mention in this context. The way the 4th Amendment is implemented in the USA isn't anything remotely like "you have the right to kill a police officer that is searching you unreasonably." The way it is implemented is "the prosecution cannot use evidence that was obtained through an unreasonable search." If a police officer insists on searching you, your property or residence, you are not required to consent, but you are also not allowed to use force to stop them. The dispute about the reasonableness of the search is supposed to happen at the court.
They can't get in unless you let them. The Wired article is giving an incorrect impression that the FCC claims that it has the right to enter homes at will to inspect radio transmitters. That simply is not the case. You have an obligation to allow the FCC to inspect your equipment, but that obligation does not eliminate your Fourth Amendment rights. So you can refuse to let them in. In that case, they have the authority to fine you for causing interference, or if they have evidence you have committed a crime, they can turn that over to a prosecutor.
And the resulting court case. I'm pretty sure the 4th amendment would triumph over the FCC's bullshit rule they presumably wrote themselves.
Indeed.
The Wired article we're discussing makes me really suspicious. Note that the article does not report any instance of anybody in the FCC actually entering somebody's residence. The only actual case they cite involves the FCC imposing a $7,000 fine on a pirate radio operator who refused to allow them to inspect the premises (and whose home was not entered, because he refused). TFA very clearly implies that the guy admitted to be running a radio transmitter (the FCC guys left after he agreed to turn it off). So basically, he's been served a fine for refusing inspection of a transmitter that he admitted to operating.
It sounds to me like both of these are true: (a) you have 4th amendment rights against unreasonable searches; (b) you have an obligation to allow the FCC to inspect radio equipment that you operate. The real question is what's the correct balance between these. Clearly it's not allowing the FCC to conduct arbitrary searches of people's homes, but I haven't seen any materials at all that can be reasonably construed to say that the FCC claims that right for itself.
A better question is: why is Slashdot giving this guy a soapbox in the first place? He's really not got a lot of insight into the legal stuff. Take for example, his "Judge Rules That I Own Slashdot" piece, where not only he proceeds to blame the judge for his own very badly argued case, but remains completely oblivious throughout to the flaws in his argument.
For example, Haselton consistently expects that the judge must accept his unsubstantiated statements about the facts of the case as true, and dismiss the spammer's retorts as false. He never stops to notice that the judge is obligated to treat Haselton's unsubstantiated truths the same as the spammer's unsubstantiated falsehoods. No, he just thinks that he ought to win, and if the judge doesn't let him win, it must be because the judge is stupid. (And of course, this tells you what Haselton's full paragraph of hatin' on the legal profession in the present piece comes down to.)
And more generally, what's the deal with Slashdot and "frequent" contributors à la Haselton, the late Piquepaille, or that other guy whose name I forgot? Do they pay Slashdot for increased access? Are they folks who met Malda on a convention, drank him under the table, and got him to sign some stuff?
For a lot of speciation (like physical separation of populations), you wouldn't have the data to draw the line if you tried.
No, you're still missing GP's point. Imagine you could gather whatever data you wanted. What data would allow you draw the species lines in the tree of life?
The problem is that modern biology shows that that line is arbitrary; common descent means that what appear to be separate "species" are just pairs of ring species where the intermediate populations have died off. And in particular, whether Neanderthals could or did breed with us is a controversial topic; the "did not breed" is the leading theory right now, but it hasn't killed the "did breed" one just yet.
You might say that several all ready did offer you the option to play from the german side, but not on the box cover. Look at the art for games with two sides like the venerable Close Combat series. It is pretty clear who you are supposed to be playing. That you can also optionally play as the germans is just a small side note.
In Panzer General, the campaigns can only be played as the German side. It's only the individual scenarios that can be played as the allies. Also, there are plenty of board wargames out there where one of the players must take the German side of WWII.
Mind you, these games abstract away from the violence part, to focus on things like tactics, strategy and logistics. Which I think is one of the reasons why wargames get a pass while Call of Duty doesn't: an FPS is a game that focuses on violence, and thus, is much more vulnerable to accusations that it glorifies violence, or at the very least profits from an audience that glorifies violence. (Another reason is that wargames are strategic games that force you to think harder about the situation on the map, and by extension, the historical situation.)
At least two American Generals were fired for using their knowledge of D-Day as after-dinner conversation at some cocktail parties.
And the Nazis did hear about the planned Normandy landings. However, they Allies also fed them a lot of false information as counterintelligence, and the Nazis were skeptical that the Allies would land on Normandy anyway. So it's more like the Nazis heard about the planned Normandy invasion, and one through Bretagne, and a Norway invasion, and a southern France invasion (straight from the mouth of a fake Bernard Montgomery), and so on; and they failed to tell which of those was true.
So really, you can hardly ever keep big secrets like D-Day from leaking; what intelligence agencies do is to try to prevent the enemy from believing the leaks.
My argument is about the legality of the methods, not how creepy they make people feel. Either you have a reasonable expectation of privacy in regards to the location of your vehicle on public roads or you don't.
Let's grant that you do not have a reasonable expectation of privacy in that regard. It doesn't follow that the cops should have an unrestricted power to surveil the population.
To address your second point: Are you saying that if the GPS receiver cost a billion bucks, required a PhD to interpret, and required a platoon of cops to monitor (factors that would tend to decrease its use) it would magically become just fine, even though it would produce the same information from the same method?
Depends what you mean by "the same information," but basically, yes.
I think you're focusing too much on the mechanisms of police surveilance and information gathering, and not nearly enough on the effects of specific surveilance practices. The issue is not what information is produced by which method; the issue is what practices do the police adopt, and what effect do those practices have on the people. If the cops use affordable GPS tracking devices to cheaply track large numbers of people that they have little cause to investigate, then some restriction must be put on them to prevent them from doing so. A reasonable restriction, which would have the desired effect, is to require a search warrant for GPS tracking.
An evidence-gathering method does not become less legal just because it is cheap and easy.
And again, this is just completely misframing the issue. It's not whether an evidence-gathering method is legal; it's about what evidence-gathering practices the cops should be allowed to use, and what measures will restrict them accordingly.
It's exactly the opposite a lot of the time. Often, private citizens can do something for which a cop would require a warrant.
This may be true in some cases, but make sure you don't get it mixed up with another thing that isn't quite the same:
If a cop performs an unwarranted search and finds evidence of a crime, that evidence must be thrown out in court.
If a private citizen performs an illegal search and finds evidence of a crime, that evidence is admissible in court.
The second one isn't really a case of private citizens being allowed to do things that the cops aren't; a private citizen isn't allowed to break into your house and search your stuff, period. However, to the extent that the break-in and search wasn't prompted by the authorities, any information they uncover about you may be used as evidence against you. (There are some gray areas having to do with the cops prompting a private citizen to search or surveil a suspect.)
Slashdot Mirror
You should not draw too many conclusions about the results of those two without taking into account the fact that both are whole-program optimizing compilers. Those two systems just do not support separate compilation of individual source files; if you change one line of one file in your program, every file must be recompiled.
This type of compiler has a performance advantage over the more common separate compilation systems, simply because it can inline anything anywhere, and thus optimize far more aggressively. But it's next to useless for developing large software systems, and thus mostly really useful only for writing smallish programs, in very high-level style, that perform some really expensive computations really fast.
Because she's talking about the SCOTUS' actual record in deciding cases about gender and race issues when the court was all white male. She's not talking about hypotheticals, she's talking about history. It's right there in the next paragraph:
Um, no, you're reading that completely backwards. I'll quote that bit again:
The key word there is "whether." That sentence is not endorsing either inherent physiological or cultural differences"; it's disclaiming the assumption of either, for the sake of the point that she's making.
Not so fast. It is certainly true that a stop-and-copy algorithm has lower algorithmic time complexity than manual memory management--but it uses more memory, in more than one sense: (a) copying from the old heap to the new heap requires that a new heap be allocated; (b) doing a collection requires touching a lot of memory pages which would otherwise not be touched often, which increases the size of the program's memory working set, limiting the virtual memory manager's ability to manage system memory.
This is extremely tricky, because again, collection touches memory pages that the program wouldn't touch otherwise, which can offset the benefit from compacting.
There's a more fundamental point to be made here. The idea that the law can be applied "objectively," according to its "plain meaning," assumes that there is such a thing as the "plain meaning" of a text. You bring up the point that a text can be written in a confusing or unclear manner, but that point can be driven a lot further: there is no way to write a text so that it carries its meaning intrinsically within it. Text is something that's used by people; without people who read it and appeal to it to justify concrete choices, text is just stains on paper.
What Judge Sotomayor is saying there is that what the law achieves is not an "objective stance," but rather a compromise between a "series of perspectives." Another way of putting this is that the point of the law is not to state truths, but rather, to resolve disputes between people, by appealing to disinterested third parties (judges, the elders of a neighboring clan, etc.) to decide the issue. But this disinterest is imperfect, because of the third parties' biases and sympathies.
Yeah. The poor man is now relegated to Director of the White House's National Economic Council for President Barack Obama. Horrible fate.
This statistic is a big lie, in that it fails to put the number in a correct context; see this article.
So yes, 60% of her decisions that the Supreme Court reviewed were overturned. The problems are:
I think what you're asking me to do is, in practice, quite flawed. The whole point of having a 4x5" sensor would be to have a hell of a lot more pixels than existing camera sensors. Assuming equivalent pixel densities, this would be 6x as many pixels as a 56x36mm medium format sensor, 14x as many pixels as full-frame 35mm sensors, and 33x times as many pixels as APS-C sized sensors. Compared to a Phase One 40MP 56x36mm sensor, an equivalent 4x5" sensor would have 234 megapixels.
Think of it this way: in the world of film, the advantage of large format over small format comes down to a very simple factor: for a given print size, large format film needs a lot less enlargement. An 8x10" print from 35mm film is an 8.5x linear enlargement; in terms of area, it's 71.7x. The same print from 4x5" film is a 2x linear enlargement. That means finer grain and better tonality.
This logic, however, doesn't translate to digital if you keep the number of pixels constant, because the pixel count puts a hard upper boundary on the resolution of the prints you wish to make. An 8x10" print from a 39 megapixel 4x5" sensor is not going to have more resolution than one from a 39MP 56x36mm one. It may (perhaps!) have better color and less noise, but if that's all you were after, you wouldn't make a sensor with 6x the area!
So yeah, it's fair to say that I implicitly assumed that a 4x5" digital sensor would have more pixels.
Compared to a smaller sensor, the larger sensor requires a larger lens to produce the same field of view. So while the amount of light that enters the camera is determined by the size of the lens, in practice the size of the lens is related to the size of the sensor.
Double-check that those are 3"x4" sensors, and not scanning backs. Scanning backs are, basically, putting a scanner on the back of a camera, so you can guess how slow those operate. (Not to mention you need controlled lighting and a still scene; i.e., good for product photography in the studio, not so good for landscapes, awful for people.)
Polaroids can still be useful for previewing exposures in large-format photography, which is still a film world. They simply don't make 4x5" digital sensors, period.
Using a digital camera to take a test shot can be useful in the same situation, but that means using a separate camera, from a slightly different angle, potentially different field of view, etc.
Once you get things like branch prediction, speculative execution and pipelining into the picture, no, C isn't really any closer to how the processors operate. Making efficient use of a modern CPU involves detail at a much, much lower level than C exposes.
The performance killer for high-level languages isn't really the abstraction away from the machine instruction set; it's garbage collection. And even then, it's mostly because GC tends not to play well with memory caches and virtual memory; a simple stop-and-copy garbage collector is actually algorithmically more efficient than malloc/free, but absolutely atrocious with caches and VM.
But there is law that specifies when you must obey the commands of a police officer, and those laws are constitutional. For example, there exist constitutionally valid laws that prohibit you from using lethal force to resist an arrest by a police officer who's identified himself to you. Those laws remain applicable even if the police are arresting you for violating an unconstitutional law.
The principle stated earlier in this thread very much applies here: it's the courts decide whether a law is constitutional, not you, period.
The article is misleading. I mean, read the thing, and note the fact that it's pirate radio operators (people who are operating powerful, unlicensed transmitters) putting words into the mouth of the FCC. Ask yourself: why would a bunch of pirate radio operators want to portray the FCC as a Gestapo-like agency?
Um, take this scenario: the FCC has evidence that you're operating an unlicensed radio station at your home. They come to your home, knock on your door, and ask to inspect the equipment. You refuse to allow them to enter. At that point, they leave, and when they get back to the office, they fine you for $7,000 dollars.
The law in question gives the FCC the authority to do that. How was the 4th Amendment violated here?
There's another extremely important thing that we should mention in this context. The way the 4th Amendment is implemented in the USA isn't anything remotely like "you have the right to kill a police officer that is searching you unreasonably." The way it is implemented is "the prosecution cannot use evidence that was obtained through an unreasonable search." If a police officer insists on searching you, your property or residence, you are not required to consent, but you are also not allowed to use force to stop them. The dispute about the reasonableness of the search is supposed to happen at the court.
They can't get in unless you let them. The Wired article is giving an incorrect impression that the FCC claims that it has the right to enter homes at will to inspect radio transmitters. That simply is not the case. You have an obligation to allow the FCC to inspect your equipment, but that obligation does not eliminate your Fourth Amendment rights. So you can refuse to let them in. In that case, they have the authority to fine you for causing interference, or if they have evidence you have committed a crime, they can turn that over to a prosecutor.
Indeed.
The Wired article we're discussing makes me really suspicious. Note that the article does not report any instance of anybody in the FCC actually entering somebody's residence. The only actual case they cite involves the FCC imposing a $7,000 fine on a pirate radio operator who refused to allow them to inspect the premises (and whose home was not entered, because he refused). TFA very clearly implies that the guy admitted to be running a radio transmitter (the FCC guys left after he agreed to turn it off). So basically, he's been served a fine for refusing inspection of a transmitter that he admitted to operating.
It sounds to me like both of these are true: (a) you have 4th amendment rights against unreasonable searches; (b) you have an obligation to allow the FCC to inspect radio equipment that you operate. The real question is what's the correct balance between these. Clearly it's not allowing the FCC to conduct arbitrary searches of people's homes, but I haven't seen any materials at all that can be reasonably construed to say that the FCC claims that right for itself.
A better question is: why is Slashdot giving this guy a soapbox in the first place? He's really not got a lot of insight into the legal stuff. Take for example, his "Judge Rules That I Own Slashdot" piece, where not only he proceeds to blame the judge for his own very badly argued case, but remains completely oblivious throughout to the flaws in his argument.
For example, Haselton consistently expects that the judge must accept his unsubstantiated statements about the facts of the case as true, and dismiss the spammer's retorts as false. He never stops to notice that the judge is obligated to treat Haselton's unsubstantiated truths the same as the spammer's unsubstantiated falsehoods. No, he just thinks that he ought to win, and if the judge doesn't let him win, it must be because the judge is stupid. (And of course, this tells you what Haselton's full paragraph of hatin' on the legal profession in the present piece comes down to.)
And more generally, what's the deal with Slashdot and "frequent" contributors à la Haselton, the late Piquepaille, or that other guy whose name I forgot? Do they pay Slashdot for increased access? Are they folks who met Malda on a convention, drank him under the table, and got him to sign some stuff?
No, you're still missing GP's point. Imagine you could gather whatever data you wanted. What data would allow you draw the species lines in the tree of life?
The problem is that modern biology shows that that line is arbitrary; common descent means that what appear to be separate "species" are just pairs of ring species where the intermediate populations have died off. And in particular, whether Neanderthals could or did breed with us is a controversial topic; the "did not breed" is the leading theory right now, but it hasn't killed the "did breed" one just yet.
How about Panzer General?
In Panzer General, the campaigns can only be played as the German side. It's only the individual scenarios that can be played as the allies. Also, there are plenty of board wargames out there where one of the players must take the German side of WWII.
Mind you, these games abstract away from the violence part, to focus on things like tactics, strategy and logistics. Which I think is one of the reasons why wargames get a pass while Call of Duty doesn't: an FPS is a game that focuses on violence, and thus, is much more vulnerable to accusations that it glorifies violence, or at the very least profits from an audience that glorifies violence. (Another reason is that wargames are strategic games that force you to think harder about the situation on the map, and by extension, the historical situation.)
I think the 50+ year old board wargame industry might be a better example. They have gotten some flack, but hardly ever this public.
And the Nazis did hear about the planned Normandy landings. However, they Allies also fed them a lot of false information as counterintelligence, and the Nazis were skeptical that the Allies would land on Normandy anyway. So it's more like the Nazis heard about the planned Normandy invasion, and one through Bretagne, and a Norway invasion, and a southern France invasion (straight from the mouth of a fake Bernard Montgomery), and so on; and they failed to tell which of those was true.
So really, you can hardly ever keep big secrets like D-Day from leaking; what intelligence agencies do is to try to prevent the enemy from believing the leaks.
Let's grant that you do not have a reasonable expectation of privacy in that regard. It doesn't follow that the cops should have an unrestricted power to surveil the population.
Depends what you mean by "the same information," but basically, yes.
I think you're focusing too much on the mechanisms of police surveilance and information gathering, and not nearly enough on the effects of specific surveilance practices. The issue is not what information is produced by which method; the issue is what practices do the police adopt, and what effect do those practices have on the people. If the cops use affordable GPS tracking devices to cheaply track large numbers of people that they have little cause to investigate, then some restriction must be put on them to prevent them from doing so. A reasonable restriction, which would have the desired effect, is to require a search warrant for GPS tracking.
And again, this is just completely misframing the issue. It's not whether an evidence-gathering method is legal; it's about what evidence-gathering practices the cops should be allowed to use, and what measures will restrict them accordingly.
This may be true in some cases, but make sure you don't get it mixed up with another thing that isn't quite the same:
The second one isn't really a case of private citizens being allowed to do things that the cops aren't; a private citizen isn't allowed to break into your house and search your stuff, period. However, to the extent that the break-in and search wasn't prompted by the authorities, any information they uncover about you may be used as evidence against you. (There are some gray areas having to do with the cops prompting a private citizen to search or surveil a suspect.)