Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

We’re Testing the Wrong People

theatlantic.com

Post reply on HN
Print view View original

101–110 of 155 posts

Re: We’re Testing the Wrong People

#101

Post by lostapathy »

ctoth wrote: post #57
heraclius wrote: post #49

Earlier quoted context omitted.

The target is to ensure that each case infects no more than one additional person (‘R Each infected person will come into contact with some other people. Testing allows three things— - first, we can tell this person to stay at home and so stop them from infecting more people; - second, we can tell the people they have seen to stay at home with good contact-tracing, so that even if they get it they don’t spread it fur…

So I guess I'm still not seeing this. Can you give me a concrete idea of what this looks like? Let's assume that it is the middle of August and the food situation is still somehow stable, I install my contact tracing app, I get a clean test. Then what? If we miss one person, that one person can still infect an entire office building by coughing in an elevator. Because of the two week incubation period, those people w…

The objective isn't to eradicate the virus at this point - that ship has sailed. The goal is to catch enough cases early enough that we can direct just the exposed people to isolate so that we can keep the total patient load at a manageable level without needing to keep the economy on pause forever.

Re: We’re Testing the Wrong People

#102

Post by enchiridion »

LolWolf wrote: post #36
munificent wrote: post #32

> Another promising pathway is to pool many tests and run them together. If a pooled sample tests negative, everyone in the pool is negative. If it is positive, the members of the pool can be tested individually. Well, it took a global pandemic, but we finally found a use for bloom filters!

This idea is called group testing [0] and has been used by the army for quite a while. It is also a well-studied problem in information theory as a (useful) basic model and we know optimal solutions to it. What is surprising is that group testing tells us that we can actually do better : the specific construction you pinpoint the people who come up positive, without needing to have a test for each person [1] and this…

So you might together the samples before testing?

Re: We’re Testing the Wrong People

#103

Post by WrtCdEvrydy »

user5994461 wrote: post #76
_Anken wrote: post #37

Earlier quoted context omitted.

Most nursing home deaths are not getting tested either.

France started testing systematically in EHPAD (nursing home for retired fully dependent elders). That's why they have the most dramatic fatality rate out of every country now. Not sure it was a good idea to test and attribute all the deaths to COVID.

It's difficult because you don't want to use test kits on dead people.

Re: We’re Testing the Wrong People

#104

Post by GavinMcG »

013a wrote: post #94
theaeolist wrote: post #62

Earlier quoted context omitted.

In tests/capita US is 42nd. https://www.worldometers.info/coronavirus/#countries

Sometimes, I feel like concepts such as these need to be translated into terms the average hackernews reader will understand. Let's say your key metric you're trying to maintain or improve is P50 request latency. Its relatively easy to exhibit an acceptable P50 to 10 users, from 1 VM. Its actually harder to deliver the same P50 to 100 users, from 10 VMs. Even harder for 1000 users and 100 VMs, snd so on. You run into…

> average hackernews reader

> P50 request latency

I for one don't even know what P50 means.

Re: We’re Testing the Wrong People

#105

Post by scott00 »

blueplanet200 wrote: post #53
exhilaration wrote: post #35

Earlier quoted context omitted.

Because we don't have enough tests. We could reopen the country if we could test enough people, but we're stuck. Even in New York and New Jersey, tests are still limited to symptomatic people because there isn't enough testing capacity.

It's a problem of limited resource allocation. The _point_ is that we have limited tests, so given limited supply why are we wasting the tests on those we think are sick. The limited supply could still be directed towards asymptomatic carriers. Wouldn't be testing everyone we want, but it's still more valuable than the allocation of tests right now.

It's far too widespread right now to successfully control via contact tracing and isolation, even if we had infinite testing capacity. The optimal use of testing right now is whatever produces the largest number of positive results, so that large case counts stay in the headlines, helping to ensure political support for stay at home orders. And that's more or less how the tests are being allocated.

Re: We’re Testing the Wrong People

#106

Post by tptacek »

leereeves wrote: post #92
tptacek wrote: post #89

Earlier quoted context omitted.

Since there are literally laws on the books in many states that explicitly delegate this power, for this precise purpose, "invented out of whole cloth a few months ago" seems an extraordinary claim. Find a credible source? When you do so, remember that the "lockdown" we're experiencing falls far short of a "general quarantine". You can in fact leave your house, and travel between states, free from pretty much any tra…

Closing the bars, and the churches, gun stores, courthouses... This lockdown is infringing on pretty much all our Constitutional rights, across the board.

It is if you assume your Constitutional rights are that that any citizen intuits from a casual reading of the Bill of Rights. It suffices in this context to point out that, if you're an American, you don't live in a country that operates on that principle; we've had centuries of jurisprudence that put the Bill of Rights into actual practice, and many of the principles routinely assumed to be violating the plain meaning of the amendments were established by the framers of those amendments.

(Courts, for what it's worth, continue to function).

Re: We’re Testing the Wrong People

#107

Post by afpx »

cm2187 wrote: post #78
ajross wrote: post #70

Earlier quoted context omitted.

That's a misunderstanding of how death works. Everything is a comorbidity on some level. > just accelerated something that would have happened within a few months anyway That's absolutely not what this means. Asthma is a comorbidity. Are asthmatics just a few months from death? I have hypertension, am I about to kick the bucket? Sixty percent of the US population (no doubt including many of the posters on this very t…

The study I got these numbers from doesn't seem to classify asthma or obesity as a comorbidity. The largest ones are hypertension, diabetes, ischemic heart disease, atrial fibrilation, active cancer in past 5y, heart failure, COPD, dementia, stroke and chronic liver disease. Not familiar with all items in this list but some seem pretty serious.

This shows the full list of conditions that are high risk: https://www.health.harvard.edu/diseases-and-conditions/if-yo...

A lot of people fall into those categories.

Re: We’re Testing the Wrong People

#108

Post by awinter-py »

pirocks wrote: post #74
awinter-py wrote: post #34

sampling bias debate reminds me of this stats legend from ww2: the USAF wanted to armor planes where the bullet holes were. statistician abe wald recommended armoring where the bullet holes weren't on the theory that those were the non-survivable hits can't interpret a statistic until you think about what's excluded from the sample

When I first heard this story it was the RAF not the USAF. I somewhat doubt how true it was.

yup, 'stats legend', not history

there's an american math society article about this -- it evaluates the fun version of the story in the context of wald's actual paper and a journal entry by another scientist named wallis

Re: We’re Testing the Wrong People

#109

Post by leereeves »

tptacek wrote: post #106
leereeves wrote: post #92

Earlier quoted context omitted.

Closing the bars, and the churches, gun stores, courthouses... This lockdown is infringing on pretty much all our Constitutional rights, across the board.

It is if you assume your Constitutional rights are that that any citizen intuits from a casual reading of the Bill of Rights. It suffices in this context to point out that, if you're an American, you don't live in a country that operates on that principle; we've had centuries of jurisprudence that put the Bill of Rights into actual practice, and many of the principles routinely assumed to be violating the plain meani…

Jury trials have been postponed all over the country.

And we can't go 2 years without jury trials while waiting for a vaccine. We'll have to find less restrictive ways to coexist with this virus.

Re: We’re Testing the Wrong People

#110

Post by kube-system »

yason wrote: post #41
alex_young wrote: post #3

The only data that is somewhat reliable in this pandemic is COVID deaths. Testing the population that is very sick / dying is crucial to understanding the baseline for the worst part of the problem. Once you have that under control, and we are not nearly there yet, you have to get every first responder tested regularly so you can prevent them from spreading the disease and give them some assurance that coming to work…

Deaths can lie too. What does it take for a death to be labelled as covid-19 death? That the person who died was merely tested positive, or do they do autopsies for all those who tested positive? How about covid-19 deaths that aren't counted as covid-19 deaths, for a reason or another? How about people dying less of regular influenza this year because of covid-19 and lockdowns? Even looking back at monthly 2020 death…

Many coroners in my state have been quoted as saying they are unable to test the dead, as tests are prioritized for the living. Our state health department says that they do not report suspected COVID-19 deaths to the CDC if the person did not test positive.
Post reply on HN