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Old 2020-03-20, 15:10   #232
retina
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Quote:
Originally Posted by S485122 View Post
The statistics of one country, South Korea, could be less biased because of their hunting up all contacts of infected people and testing them.
The selection criteria are still biased towards finding infected people, and ignoring people they think are not involved.
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Originally Posted by CRGreathouse View Post
You can get a decent idea with stratified random sampling, but we don't even have enough tests for that right now. It would be very useful, though, because it would give an idea of the level of community-acquired COVID-19.
I don't quite understand what you mean by "stratified random sampling". If that is the same as ordinary random sampling then I agree.
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Old 2020-03-20, 18:15   #233
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Chinese Authorities Admit Improper Response To Coronavirus Whistleblower
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Li Wenliang, the ophthalmologist whose early warnings about the coronavirus earned him a reprimand from Chinese authorities, is finally receiving justice — albeit posthumously. Authorities in the country are apologizing to his family and dropping their reprimand, six weeks after his death from the disease caused by the virus.

Widely known as a whistleblower who spoke up about the outbreak in the city of Wuhan, China, the 34-year-old doctor was initially punished by local authorities. They said he was "spreading rumors" in early January, after he had tried to warn others about the emergence of the novel coronavirus that has now become a global pandemic.
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Old 2020-03-20, 19:06   #234
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Yes, and it's even worse than that.
More precisely, local officials arrested several local doctors on Jan 1 and 2 more on Jan 3, with accusations they were spreading FALSE rumors, and used the power of the state to try to intimidate them into participating in suppressing the truth and coerce them into going along with the state's preferred falsehoods. For weeks afterward, there was a pretense that it was not capable of spreading human to human.

The world situation would be very different now if the initial official reaction had been more enlightened and reality-based in China. They had a real opportunity to drastically reduce the worldwide impact compared to what it already is. That would also have benefited China's economy, world image, and the residents of the Hubei province.
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Old 2020-03-20, 19:10   #235
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Quote:
Originally Posted by Uncwilly View Post
The highlighted number is highly biased by that facility in Washington state.
Less so by the day as the 34 deaths from the nursing home get diluted by the rest of the nation's fatalities. And I noted the significant impact of that location with the previous days numbers.
I've seen claims that some of the low paid help at that nursing home were reporting to work while themselves ill. And the misdiagnoses certainly didn't help. They had nearly complete infection of the patients, at 81+34=115 out of 120.

https://www.beckershospitalreview.co...monia-flu.html

Last fiddled with by kriesel on 2020-03-20 at 19:17
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Old 2020-03-20, 19:37   #236
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Quote:
Originally Posted by retina View Post
All the numbers are biased and useless. You need to test the entire population to know the actual figures.
No.
Population,
fraction that has exhibited enough symptoms to attract medical attention,
fraction diagnosed as the disease in question times,
fractions of those diagnosed as having disease X, that recover or die,
contain useful information, as do time trends in each.
Without providing means of calculating any individual's odds of becoming exposed, or infected, or clinical, or dead.
Exhaustive testing would only provide a snapshot in staggered time anyway. The situation would have changed for someone before one round of testing of every person could have been completed.

A useful and encouraging figure is that the Washington state nursing home had 81 sickened, and 34 dead, out of a confined and vulnerable population of 120; 5 apparently escaped it entirely, in about the worst scenario there is, as it ran rampant unidentified for about a month in close proximity.

Last fiddled with by kriesel on 2020-03-20 at 19:50
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Old 2020-03-20, 19:45   #237
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Quote:
Originally Posted by Uncwilly View Post
California now has what amounts to a "STAY the ____ HOME" order.
You can go out and walk around. Go to the park, but stay away from people. Stores that are non-essential (selling things like clothes, electronics, books, etc.) are to close. Some guberment workers are to stay home.
Found out yesterday that the local coffee joint, Dr. Insomniac's, remains open for business, like other food service places it's in takeout-only mode, but the owner lady said it's OK to sit at the outside tables, the local cops have been doing it themselves - just maintain distance from other parties using the area. Downstairs Whole Foods remains open, just on slightly reduced hours, lotsa empty shelves due to the mass-stocking-up tsunami, but the manager says they're getting new supply in, they just don't usually order TP by the truckload in their weekly purchasing. :)
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Old 2020-03-20, 21:59   #238
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A plausible reason why Northern Italy has been so disproportionally hard-hit by Covid-19:

https://www.newyorker.com/magazine/2...ags-in-tuscany

Long story short, large numbers of Chinese workers in the textile regions of Italy. Their job, disassemble the machinery to send it to China, or work in the region's famous textile plants for cheap.

A phrase (not my coinage) comes to mind: "Globalization is a disaster everywhere you care to look." Thanks for that, "unchallenged-for-over-50-years consensus of nearly all of the world's leading economists".

Last fiddled with by ewmayer on 2020-03-20 at 21:59
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Old 2020-03-21, 01:12   #239
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Quote:
Originally Posted by retina View Post
I don't quite understand what you mean by "stratified random sampling". If that is the same as ordinary random sampling then I agree.
You could take a uniform random sample from the US at large (ordinary random sampling) and that would at least tell you the overall level of infection. If tests were really hard to come by you could sample 5 people and draw very weak conclusions about the overall level: if none of them are infected or have antibodies (and hence have been previously infected*), we can say with 95% confidence that at most 1-.05^(1/5) ≈ 45% of the population is or was infected.

With more resources you could test 1000 people uniformly at random throughout the country (like polling agencies do!) and get decent error bars on the percentage, something like 0.2%.

But when you know more about the disease and its distribution, and have the resources to take advantage of that, it makes sense to stratefy instead of taking the whole population as a uniform chunk. For example, you might sample Rockland and King more heavily (geographic stratification), you might age-stratefy because the virus acts differently on different age groups, or you might simply oversample the elderly because they are at higher risk. You might similarly oversample other at-risk populations like the institutionalized, especially those in nursing homes. Normal sampling will miss these populations, which are a small percent of the overall population but appear to represent a large percentage of COVID-19 risk.

* For the purpose of this exercise, we'll suppose immune memory is sufficient.
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Old 2020-03-21, 01:41   #240
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Quote:
Originally Posted by ewmayer View Post
A phrase (not my coinage) comes to mind: "Globalization is a disaster everywhere you care to look."
Cases in point:

Imports of medical supplies plummet as demand in US soars
Quote:
The critical shortage of medical supplies across the U.S., including testing swabs, protective masks, surgical gowns and hand sanitizer, can be tied to a sudden drop in imports, mostly from China, The Associated Press has found.

Trade data shows the decline in shipments started in mid-February after the spiraling coronavirus outbreak in China led the country to shutter factories and disrupted ports. Some emergency rooms, hospitals and clinics in the U.S. have now run out of key medical supplies, while others are rationing personal protective equipment like gloves and masks.

The United States counts on receiving the vast majority of its medical supplies from China, where the coronavirus has infected more than 80,000 people and killed more than 3,200. When Chinese medical supply factories began coming back on line last month, their first priority was their own hospitals.
US virus testing faces new headwind: Lab supply shortages
Quote:
WASHINGTON (AP) — First, some of the coronavirus tests didn't work. Then there weren't enough to go around. Now, just as the federal government tries to ramp up nationwide screening, laboratory workers are warning of a new roadblock: dire shortages of testing supplies.
<snip>
There are "acute, serious shortages across the board" for supplies needed to do the tests, said Eric Blank, of the Association of Public Health Laboratories, which represents state and local health labs.

Late Friday, Blank's group and two other public health organizations recommended that testing be scaled back due to "real, immediate, wide-scale shortages." The groups said only patients with COVID-19 symptoms who are elderly, have high-risk medical conditions or are medical staff should be tested.
<snip>
The coronavirus test uses a chemical chain reaction to detect tiny traces of the virus' genetic material and reproduce it many times. State and local health labs follow the technique first developed by the CDC, which calls for a specific genetic kit made by German diagnostic firm Qiagen. Labs around the globe are reporting shortage of those kits.

Qiagen said this week it is trying to boost production from normal levels, which are capable of testing 1.5 million patients per month, to amounts that would allow for testing more than 10 million patients by the end of June.
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Old 2020-03-21, 02:45   #241
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Yawn. Either we could have been inefficiently producing them all along, or we could have just buffered our own supply and price-signaled that we wanted more, so foreign and domestic sources get you supplies. It works decently, as long as you don't stop yourself from buying what you need. Of course if you find out your supply lines are too fragile (as our rare earths certainly were) you should diversify -- but that's a problem you could face regardless of international trade, and indeed one that becomes worse if you cut off trade.
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Old 2020-03-21, 03:09   #242
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Quote:
Originally Posted by CRGreathouse View Post
Yawn. Either we could have been inefficiently producing them all along, or we could have just buffered our own supply and price-signaled that we wanted more, so foreign and domestic sources get you supplies. It works decently, as long as you don't stop yourself from buying what you need. Of course if you find out your supply lines are too fragile (as our rare earths certainly were) you should diversify -- but that's a problem you could face regardless of international trade, and indeed one that becomes worse if you cut off trade.
"inefficiently producing" - you mean "actually paying our own country's workers a fair wage for producing them, perhaps charging a bit more for the end product, and not letting greedy CEOs ratchet up their own compensation to the moon?" Because the latter phenomenon is where a lot of the "promised cost savings" from offshoring have magically disappeared to. You prefer the "efficiency" of eliminating a huge % of once decent-paying domestic manufacturing jobs and telling their former holders to slave in Amazon warehouses without bathroom breaks, then once their bodies are broken, "go eat some opioids, deplorabes?"

And how does domestic manufacturing interfere with "diversified supply chains", in a country as large and diverse as the US? E.g. for medical masks, one would expect/require multiple maunfacturers to compete for market share. They just wouldn't be able to offshore the manufacturing pollution and so eaily be able to hide abusive workplace conditions in some distant state-owned-enterprise in China.

Also, "buffering one's supply" sounds well and good, but since one typcially doesn't know in advance what sectors will be especially hard-hit by those "exogenous supply shocks", to do it for everything one can think of is the definition of inefficiency, and an invitation for piling up unused inventory. Many of these products, even "durable" ones have limited useful shelf lives, and even so, you gotta store 'em somewhere.

A good model in my view is not so much a huge supply chain disruption but rather its converse, the huge demand spike the US experienced when it entered into WW2. The ensuing unprecedented-in-world-history crash retooling and effciency-upgrading of domestic industry was only possible because it *was* domestic industry - raw materials suppliers were able to work closely with factories, and efficiency experts were literally able to travel the entire supply chain in a matter of days or weeks and give tongue-lashings and ass-kickings (at least of the metaphorical variety) as needed.

I'm not preching xenophobia here, just a return of a significant amount of autarky, especially with respect to products which clearly are, or can very easily become, critical to national security or, as in the present crisis, public health.
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