It's the opposite really. You can publish any fucking thing by mining for a low p-value (through multiple comparisons, outright biased sampling techniques, etc., etc.) and then turning your brain off.
Of course, just getting rid of the p-value outright won't solve this, but at the very least, the problem isn't what you're saying it is. Blind math fetishism isn't solving anything.
Yeah, but then when nobody can replicate your findings, you become that lab that publishes crap all the time. Reviewers start asking for more confirmatory evidence, grant reviewers already ding you before they've even read you application, etc. Sure you can abuse the system for awhile, but eventually it catches up to you.
But irreproducible results which catch people's imagination live forever. People still believe you can transfer learned experience by grinding up planaria and feeding them to other planaria.
Actually, p-values are about CORRELATION.
Maybe *you* aren't well-positioned to be denigrating others as not statistical experts.
I may be responding to a troll here, but, no, the GP is correct. P-values are about probability. They're often used in the context of evaluating a correlation, but they needn't be. Specifically, p-values specify the probability that the observed statistical result (which may be a correlation) could be a result of random selection of a particularly bad sample. Good sampling techniques can't eliminate the possibility that your random sample just happens to be non-representative, and the p value measures the probability that this has happened. A p value of 0.05 means that there's a 5% chance that your results are bogus in this particular way.
The problem with p values is that they only describe one way that the experiment could have gone wrong, but people interpret them to mean overall confidence -- or, even worse -- significance of the result, when they really only describe confidence that the sample wasn't biased due to bad luck in random sampling. It could have been biased because the sampling methodology wasn't good. I could have been meaningless because it finds an effect which is real, but negligibly small. It be meaningless because the experiment was just badly constructed and didn't measure what it thought it was measuring. There could be lots and lots of other problems.
There's nothing inherently wrong with p values, but people tend to believe they mean far more than they do.
Yeah. p-values are much more sensitive to having a small standard deviation than they are to having a large difference between the two samples tested. So you can have a test where the differences between the two samples ranged from 3-4 be significant, while an identical test where the differences ranged from 10-30 were not significant. Thus the dependence on big sample size I discussed elsewhere.
Because identifying the 10 million and sampling the 1 million will be expensive. Worse, that many people in the class may not exist. If your class is 'residents of Boring, Oregon', there may simply be too few of them to randomize away the confounders and drive the p-value down.
Top tip. If you want to find something in the data, it helps if it sticks out above the noise floor like a sore thumb. If you're having to push the noise floor down with sample size to make something visible, the odds you got something else wrong go up in proportion.
But you are right though. If the effect is invisible until teased out statistically, it's probably not real, or at best not big enough to be interesting, and at best best nobody will believe it anyway. Especially when the raw effect goes one way, but after statistically clearing out the debris, it suddenly changes polarity. Statistics is best used as a minor tool to get a more precise estimate of an effect which is clear before you start the statistical work. But people publish that tortured out stuff anyway. To be fair, even if there's substantial doubt about a result, if it's important enough it's worth publishing just to see if people can either repeat it, refute it, or explain what the heck happened. Cold fusion being a perfect example.
Because identifying the 10 million and sampling the 1 million will be expensive. Worse, that many people in the class may not exist. If your class is 'residents of Boring, Oregon', there may simply be too few of them to randomize away the confounders and drive the p-value down.
Top tip. If you want to find something in the data, it helps if it sticks out above the noise floor like a sore thumb. If you're having to push the noise floor down with sample size to make something visible, the odds you got something else wrong go up in proportion.
Oh you really mean a sample from of a population of 10,000,000? I thought you meant a sample of 10,000,000 but were a bit imprecise in wording. You don't need a sample of 1,000,000 for a population of 10,000,000, a sample of 100 will do just fine if you are sure it's representative and randomly sampled. And if it's not representative and randomly sampled, a sample of 1,000,000 won't give you a valid answer either. That's why we can do clinical trials on a few hundred people, at most, and decide that a drug is in all reasonable probability efficacious and safe enough to be marked to a population of 600,000,000.
The other side of the problem is that a random sample of 10,000,000 people is going to find everything significantly different. That's from the inverse dependence of the standard deviation on the root of N. Given any nonzero difference between two samples, there will always be some value of N high enough that the standard deviation is therefore low enough that that difference will have a p value.05, or as low as you want it to be.
How is it subjective that, given random applications or whatever, as in the previously described test, subject A reliably responds favorably to names like George Whittington Huxley III and unfavorably to names like D'shawn Mohammed Washington, whereas the majority of subjects respond equally to both?
Statistically verifiable, and all that?
You randomize your two populations, then you test to ensure that there are no significant differences between the two populations in what you are trying to control for. If there is, like 1 group is all males and the other is all females, then "the randomization failed". Which of course is guaranteed to happen 5% of the time for each factor, so if you have 20 factors.....
"Racism", "sexism", "patriarchy" and related topics of study within the social "sciences" inherently can't be quantitatively analyzed in any meaningful way.
Yeah, based on your multiyear immersion in the field, right? And those so-called climate scientists, I bet they didn't even include solar effects. And don't get me started on medical science, they're all a bunch of quacks, one year coffee is good for you one year it's bad for you.
They have no clue in the first place what their data really look like, and know good knowledge of how to properly analyse data and make graphs. Before they even teach stats to undergrads they should be making them learn to plot data and read graphs. It's obvious most of them can't even do that.
That........
Explains why some people struggle horrifically in statistics, and others can sleep through class and still get an A.
Absolutely. A corollary of this is that many hypotheses bolstered with vast quantities of statistical analysis proving their statistical significance, become immediately ridiculous as soon as they are graphed.
By and large, the stats are irrelevant. If the effect is pretty solid, the stats will be so obviously significant that you don't need to ask the p-value. On the other hand, when the stats are so close to the line that you have to calculate the p-value and find that it's.0475; nobody else is going to believe the effect is real. Especially, nobody who knows their stuff is going to look at a paper with p=.0475 and one with p=.0525 and say with any sincerity that the first one is true and the second one is not.
That's what happens when your reviewers are the unpaid submitters of other articles to your paper.
your reviewers are in fact the competitors of the guy whose paper they are reviewing, for scarce grant money which is awarded very largely on number of publications, so the bias if any is for reviewers to trashcan the paper they review. And on another topic, submitters of articles are not only unpaid, in fact you have to pay for having your paper published.
Car Q&A column in the paper the other day had a question from somebody who had maybe a 4 year old Mustang? Hope I'm not slandering the make... Anyway, the indicator light on a switch had died, and you couldn't replace just the light, you had to buy a whole new switch for $50.
Rather the opposite - nice cars (or anything newer than 10-15 years) has integrated headunits, which is basically what kimvette says. On old/simple cars, the radio was just a radio, sitting in a DIN socket.
However, there are aftermarket solutions, some nicer than other. And of course, the nice solutions are krkrkrkrkrkrkrkrkrkrkrkrkrkr...
Recent Honda Civics, for instance. (recent meaning like back ten years, anyway); the security system and remote work through the radio, so (at least back then) you used to see a lot of aftermarket systems installed, with the original radio just stuffed back in the behind the dash wiring.
I just want the search engine to stop changing what I'm searching for. I don't want to have to quote every word like I have to do with Google to make sure that the word is actually in the page, and by "the word", I mean "the word I type, not a word that Google things may be similar to the one I typed". It's worst when you're searching for foreign words, product names, acronyms, or whatnot and Google tries to treat them as if they're English words and declines them or chooses synonyms.
"Did you mean X?" is fine. Even "Searching for X (see original results here)", if you're very confident that the person made a common spelling error or whatnot. But just going in and swapping out words as if this is expected behavior? Terrible. At least let me disable it if you want to do that...
Beyond all this: I do like how one can do simple commonn operations on Google - math, conversions, etc. The more of these the better IMHO, so long as they have a standardized format - be they tracking numbers, flight lookups, whatever. It's okay in my book to be a bit Wolfram-y.
Keep the interface plain, simple, the sort of thing that'll work on any browser, from a modern Chrome to a simple text-only browser. Only use javascript where it's not essential for the site to work. Here's an example of something that would be a good use of javascript: if you need to track clicks, like Google does, do it through javascript rather than by having a link redirect like Google does. I hate how I can't just right click and copy link on Google without getting some massive Google redirect link.
Just my thoughts.:)
I'm in the other camp on this. I appreciate whatever it is that Google is doing to widen my search to find things that might be what I'm looking for that I don't have a precisely verbatim search term for. That's something Google seems to do well. It's their ability to produce crap completely unrelated to any of the search terms due to some clever hack by the search optimizer scum that annoys me.
and while I"m at it, I"d like to see more stuff that is something a person might be searching for, and fewer results that are some high school kid's twitter feed.
It has gotten a lot worse, hasn't it?
I want a search engine to identify when someone is attempting to manipulate it and to counter that. I don't want Google Bombs like "miserable failure" regardless of how I feel about the actual politics, to make the results useless. I'm not so childish as to expect an echo-chamber everywhere I look.
This means no more companies whose entire existence is to try to improve someone's search rankings.
As to data being collected, I'm actually okay with the top 80% of searches in a given day being used for advertising revenue, assuming no geographic data beyond nation, and no personally-identifiable data is collected. That's how a search engine would make money, by selling ads based on what people want to know about. If Ford has a press-release about the new Focus, and people search for that, I'm okay with ads related to the Focus or to Fords coming up. I just don't want more than "this term is being asked for this many times on this day" to be reported.
amen. I'm sick of searching for "painful rectal itch" and having the first two pages of results all offering to sell me the best painful rectal itch at the lowest prices.
Actually a search engine is one of the few things where the cost depends less on use and more on the amount of the Internet you would like to index. It takes a lot of storage and processing power to create an easily-searchable index of the Internet.
Indeed. Economies of scale most definitely doesn't sound like something an internet search engine would experience. Quite the opposite.
What is 'general intelligence'? (Anything like Colonel Panic?)
Yes, if you can't read, can't figure out a bus schedule you are in a world of hurt in this society. It does not follow that being able to understand calculus gives you peace, happiness and longevity. There is going to be some broad mean that societal requirements dictate that you need. Other than than, you are at the mercy of lots of other vagaries of life.
Indeed. just because a square peg fits better into a square hole than a round peg, doesn't mean that if you add additional vertices it will fit even better.
Unfortunately, this is largely the natural progression of society. Back then, we didn't know how to handle these kids, thus we ham stringed them from the get go. They had the unfortunate luck to be born at a time when we're just awakening to the idea that we should treat children differently than adults, and with absolutely NO awareness that different children require different rearing techniques.
The good news is that, despite all the bullshit,we really have progressed quite far. I doubt, 80 years from now were you to quiz a similar group of kids from today, you'd get the same response. No, instead you might hear how society let them down, that they always felt society always failed to live up to their expectations.
Ah, progress!
General truth. Pet owners learn that the more intelligent a pet is, the tougher it is to handle; of course, the corollary is that if you can handle them properly, they can be more rewarding. The same is true of kids.
We have too many people in college / higher levels of the ivory tower some maybe very smart but at times in some fields when it comes down to real world work experience (out side of the ivory tower) they can be very dumb.
thats such a cliche, though. one could say that sometimes smart people can have tons of real world work experience, but when it comes down to analytical, theoretical understanding, they can be very dumb.
of course, that can be said of any two types of knowledge, besides ivory tower/real world. science/arts, for instance.
Intelligence is a weaker selection trait in the wild then, say, strength, stamina, endurance and mate attraction.
It only becomes worthwhile once you have a stable society and can then pursue such "luxuries" and, even then, it appears to take thousands of years to become critical to society in general and, even now, it's still not considered a "desirable" trait for mate attraction...
Similarly; the next most intelligent creatures on earth, chimpanzees, even the other great apes, even the rest of the primates, are nothing more than a footnote in the book of earth's fauna, nor have they ever been terribly significant; and if humanity should vanish there is no possibility that their dominant place in the global ecology will be even partially assumed by apes, despite what the movies say.
"Why the fuck do you make the idiotic claims that you do?"
Useful idiots are useful idiots. Ever notice that those who denigrate European and US culture are almost always leftists? They are communism's "useful idiots".
ever notice that those who have nothing but anecdotal evidence are so certain of themselves? Presumably, a presidential candidate who castigates nearly half the American population as freeloaders because they don't pay income tax because their income is too low (as distinct from those who pay no income tax because they have loophole-scenting lawyers) doesn't count as "denigrating US culture". No, he admires it totally, except for the parts of it he doesn't like.
Nothing is as sharp as obsidian. It's still used in some surgery.
well, broken glass of all kinds, obsidian included. been a while, but we used to use broken glass for microtome knives to produce thin slices for electron microscopy.
Slashdot Mirror
It's the opposite really. You can publish any fucking thing by mining for a low p-value (through multiple comparisons, outright biased sampling techniques, etc., etc.) and then turning your brain off.
Of course, just getting rid of the p-value outright won't solve this, but at the very least, the problem isn't what you're saying it is. Blind math fetishism isn't solving anything.
Yeah, but then when nobody can replicate your findings, you become that lab that publishes crap all the time. Reviewers start asking for more confirmatory evidence, grant reviewers already ding you before they've even read you application, etc. Sure you can abuse the system for awhile, but eventually it catches up to you.
But irreproducible results which catch people's imagination live forever. People still believe you can transfer learned experience by grinding up planaria and feeding them to other planaria.
Actually, p-values are about CORRELATION. Maybe *you* aren't well-positioned to be denigrating others as not statistical experts.
I may be responding to a troll here, but, no, the GP is correct. P-values are about probability. They're often used in the context of evaluating a correlation, but they needn't be. Specifically, p-values specify the probability that the observed statistical result (which may be a correlation) could be a result of random selection of a particularly bad sample. Good sampling techniques can't eliminate the possibility that your random sample just happens to be non-representative, and the p value measures the probability that this has happened. A p value of 0.05 means that there's a 5% chance that your results are bogus in this particular way.
The problem with p values is that they only describe one way that the experiment could have gone wrong, but people interpret them to mean overall confidence -- or, even worse -- significance of the result, when they really only describe confidence that the sample wasn't biased due to bad luck in random sampling. It could have been biased because the sampling methodology wasn't good. I could have been meaningless because it finds an effect which is real, but negligibly small. It be meaningless because the experiment was just badly constructed and didn't measure what it thought it was measuring. There could be lots and lots of other problems.
There's nothing inherently wrong with p values, but people tend to believe they mean far more than they do.
Yeah. p-values are much more sensitive to having a small standard deviation than they are to having a large difference between the two samples tested. So you can have a test where the differences between the two samples ranged from 3-4 be significant, while an identical test where the differences ranged from 10-30 were not significant. Thus the dependence on big sample size I discussed elsewhere.
Because identifying the 10 million and sampling the 1 million will be expensive. Worse, that many people in the class may not exist. If your class is 'residents of Boring, Oregon', there may simply be too few of them to randomize away the confounders and drive the p-value down.
Top tip. If you want to find something in the data, it helps if it sticks out above the noise floor like a sore thumb. If you're having to push the noise floor down with sample size to make something visible, the odds you got something else wrong go up in proportion.
But you are right though. If the effect is invisible until teased out statistically, it's probably not real, or at best not big enough to be interesting, and at best best nobody will believe it anyway. Especially when the raw effect goes one way, but after statistically clearing out the debris, it suddenly changes polarity. Statistics is best used as a minor tool to get a more precise estimate of an effect which is clear before you start the statistical work.
But people publish that tortured out stuff anyway.
To be fair, even if there's substantial doubt about a result, if it's important enough it's worth publishing just to see if people can either repeat it, refute it, or explain what the heck happened. Cold fusion being a perfect example.
Because identifying the 10 million and sampling the 1 million will be expensive. Worse, that many people in the class may not exist. If your class is 'residents of Boring, Oregon', there may simply be too few of them to randomize away the confounders and drive the p-value down.
Top tip. If you want to find something in the data, it helps if it sticks out above the noise floor like a sore thumb. If you're having to push the noise floor down with sample size to make something visible, the odds you got something else wrong go up in proportion.
Oh you really mean a sample from of a population of 10,000,000? I thought you meant a sample of 10,000,000 but were a bit imprecise in wording. You don't need a sample of 1,000,000 for a population of 10,000,000, a sample of 100 will do just fine if you are sure it's representative and randomly sampled. And if it's not representative and randomly sampled, a sample of 1,000,000 won't give you a valid answer either. That's why we can do clinical trials on a few hundred people, at most, and decide that a drug is in all reasonable probability efficacious and safe enough to be marked to a population of 600,000,000.
The other side of the problem is that a random sample of 10,000,000 people is going to find everything significantly different. That's from the inverse dependence of the standard deviation on the root of N. Given any nonzero difference between two samples, there will always be some value of N high enough that the standard deviation is therefore low enough that that difference will have a p value .05, or as low as you want it to be.
How is it subjective that, given random applications or whatever, as in the previously described test, subject A reliably responds favorably to names like George Whittington Huxley III and unfavorably to names like D'shawn Mohammed Washington, whereas the majority of subjects respond equally to both? Statistically verifiable, and all that?
You randomize your two populations, then you test to ensure that there are no significant differences between the two populations in what you are trying to control for. If there is, like 1 group is all males and the other is all females, then "the randomization failed". Which of course is guaranteed to happen 5% of the time for each factor, so if you have 20 factors.....
"Racism", "sexism", "patriarchy" and related topics of study within the social "sciences" inherently can't be quantitatively analyzed in any meaningful way.
Yeah, based on your multiyear immersion in the field, right? And those so-called climate scientists, I bet they didn't even include solar effects. And don't get me started on medical science, they're all a bunch of quacks, one year coffee is good for you one year it's bad for you.
english grammer. Kelsey's cousin, who thinks he's e. e. cummings.
They have no clue in the first place what their data really look like, and know good knowledge of how to properly analyse data and make graphs. Before they even teach stats to undergrads they should be making them learn to plot data and read graphs. It's obvious most of them can't even do that.
That........ Explains why some people struggle horrifically in statistics, and others can sleep through class and still get an A.
Absolutely. A corollary of this is that many hypotheses bolstered with vast quantities of statistical analysis proving their statistical significance, become immediately ridiculous as soon as they are graphed.
By and large, the stats are irrelevant. If the effect is pretty solid, the stats will be so obviously significant that you don't need to ask the p-value. On the other hand, when the stats are so close to the line that you have to calculate the p-value and find that it's .0475; nobody else is going to believe the effect is real. Especially, nobody who knows their stuff is going to look at a paper with p=.0475 and one with p=.0525 and say with any sincerity that the first one is true and the second one is not.
That's what happens when your reviewers are the unpaid submitters of other articles to your paper.
your reviewers are in fact the competitors of the guy whose paper they are reviewing, for scarce grant money which is awarded very largely on number of publications, so the bias if any is for reviewers to trashcan the paper they review. And on another topic, submitters of articles are not only unpaid, in fact you have to pay for having your paper published.
Boy, you rich guys with your modern fancy cars with radios in them.
Car Q&A column in the paper the other day had a question from somebody who had maybe a 4 year old Mustang? Hope I'm not slandering the make... Anyway, the indicator light on a switch had died, and you couldn't replace just the light, you had to buy a whole new switch for $50.
Rather the opposite - nice cars (or anything newer than 10-15 years) has integrated headunits, which is basically what kimvette says. On old/simple cars, the radio was just a radio, sitting in a DIN socket.
However, there are aftermarket solutions, some nicer than other. And of course, the nice solutions are krkrkrkrkrkrkrkrkrkrkrkrkrkr...
Recent Honda Civics, for instance. (recent meaning like back ten years, anyway); the security system and remote work through the radio, so (at least back then) you used to see a lot of aftermarket systems installed, with the original radio just stuffed back in the behind the dash wiring.
I just want the search engine to stop changing what I'm searching for. I don't want to have to quote every word like I have to do with Google to make sure that the word is actually in the page, and by "the word", I mean "the word I type, not a word that Google things may be similar to the one I typed". It's worst when you're searching for foreign words, product names, acronyms, or whatnot and Google tries to treat them as if they're English words and declines them or chooses synonyms.
"Did you mean X?" is fine. Even "Searching for X (see original results here)", if you're very confident that the person made a common spelling error or whatnot. But just going in and swapping out words as if this is expected behavior? Terrible. At least let me disable it if you want to do that...
Beyond all this: I do like how one can do simple commonn operations on Google - math, conversions, etc. The more of these the better IMHO, so long as they have a standardized format - be they tracking numbers, flight lookups, whatever. It's okay in my book to be a bit Wolfram-y.
Keep the interface plain, simple, the sort of thing that'll work on any browser, from a modern Chrome to a simple text-only browser. Only use javascript where it's not essential for the site to work. Here's an example of something that would be a good use of javascript: if you need to track clicks, like Google does, do it through javascript rather than by having a link redirect like Google does. I hate how I can't just right click and copy link on Google without getting some massive Google redirect link.
Just my thoughts. :)
I'm in the other camp on this. I appreciate whatever it is that Google is doing to widen my search to find things that might be what I'm looking for that I don't have a precisely verbatim search term for. That's something Google seems to do well. It's their ability to produce crap completely unrelated to any of the search terms due to some clever hack by the search optimizer scum that annoys me.
and while I"m at it, I"d like to see more stuff that is something a person might be searching for, and fewer results that are some high school kid's twitter feed.
It has gotten a lot worse, hasn't it? I want a search engine to identify when someone is attempting to manipulate it and to counter that. I don't want Google Bombs like "miserable failure" regardless of how I feel about the actual politics, to make the results useless. I'm not so childish as to expect an echo-chamber everywhere I look. This means no more companies whose entire existence is to try to improve someone's search rankings. As to data being collected, I'm actually okay with the top 80% of searches in a given day being used for advertising revenue, assuming no geographic data beyond nation, and no personally-identifiable data is collected. That's how a search engine would make money, by selling ads based on what people want to know about. If Ford has a press-release about the new Focus, and people search for that, I'm okay with ads related to the Focus or to Fords coming up. I just don't want more than "this term is being asked for this many times on this day" to be reported.
amen.
I'm sick of searching for "painful rectal itch" and having the first two pages of results all offering to sell me the best painful rectal itch at the lowest prices.
Actually a search engine is one of the few things where the cost depends less on use and more on the amount of the Internet you would like to index. It takes a lot of storage and processing power to create an easily-searchable index of the Internet.
Indeed. Economies of scale most definitely doesn't sound like something an internet search engine would experience. Quite the opposite.
What is 'general intelligence'? (Anything like Colonel Panic?)
Yes, if you can't read, can't figure out a bus schedule you are in a world of hurt in this society. It does not follow that being able to understand calculus gives you peace, happiness and longevity. There is going to be some broad mean that societal requirements dictate that you need. Other than than, you are at the mercy of lots of other vagaries of life.
Indeed. just because a square peg fits better into a square hole than a round peg, doesn't mean that if you add additional vertices it will fit even better.
Unfortunately, this is largely the natural progression of society. Back then, we didn't know how to handle these kids, thus we ham stringed them from the get go. They had the unfortunate luck to be born at a time when we're just awakening to the idea that we should treat children differently than adults, and with absolutely NO awareness that different children require different rearing techniques.
The good news is that, despite all the bullshit,we really have progressed quite far. I doubt, 80 years from now were you to quiz a similar group of kids from today, you'd get the same response. No, instead you might hear how society let them down, that they always felt society always failed to live up to their expectations.
Ah, progress!
General truth.
Pet owners learn that the more intelligent a pet is, the tougher it is to handle; of course, the corollary is that if you can handle them properly, they can be more rewarding. The same is true of kids.
As intelligence goes up, happiness often goes down. See, I made a graph! I make a lot of graphs...
Happiness runs in a circular motion, happiness runs.
We have too many people in college / higher levels of the ivory tower some maybe very smart but at times in some fields when it comes down to real world work experience (out side of the ivory tower) they can be very dumb.
thats such a cliche, though. one could say that sometimes smart people can have tons of real world work experience, but when it comes down to analytical, theoretical understanding, they can be very dumb.
of course, that can be said of any two types of knowledge, besides ivory tower/real world. science/arts, for instance.
Intelligence is a weaker selection trait in the wild then, say, strength, stamina, endurance and mate attraction.
It only becomes worthwhile once you have a stable society and can then pursue such "luxuries" and, even then, it appears to take thousands of years to become critical to society in general and, even now, it's still not considered a "desirable" trait for mate attraction...
Similarly; the next most intelligent creatures on earth, chimpanzees, even the other great apes, even the rest of the primates, are nothing more than a footnote in the book of earth's fauna, nor have they ever been terribly significant; and if humanity should vanish there is no possibility that their dominant place in the global ecology will be even partially assumed by apes, despite what the movies say.
"Why the fuck do you make the idiotic claims that you do?"
Useful idiots are useful idiots. Ever notice that those who denigrate European and US culture are almost always leftists? They are communism's "useful idiots".
ever notice that those who have nothing but anecdotal evidence are so certain of themselves? Presumably, a presidential candidate who castigates nearly half the American population as freeloaders because they don't pay income tax because their income is too low (as distinct from those who pay no income tax because they have loophole-scenting lawyers) doesn't count as "denigrating US culture". No, he admires it totally, except for the parts of it he doesn't like.
Nothing is as sharp as obsidian. It's still used in some surgery.
well, broken glass of all kinds, obsidian included. been a while, but we used to use broken glass for microtome knives to produce thin slices for electron microscopy.