[aslyfox]

Heard a good slogan just now

If you are out and about

Help a neighbor out

Wear a face mask

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Last edited by aslyfox; 04-06-2020 at 06:32 AM.

[photoptimist]

my problem with all of the modeling

[ which is essential do not misunderstand me ] is that it is dependant on accurate data

and the question is whether the data is accurate

I am not suggesting a conspiracy of any sort

just the experience of the world, as I understand it,

rarely is the data on which we make decisions 100 % correct

Yes, GIGO affects all models, especially forecasting models that combine exponential growth of the virus and inexplicable human behavior.

However, there are a wide range of computational, mathematical, statistical, and scientific approaches that can tackle the problem. They can make the most of the sparse data we do have, account for the uncertainties in that data, correct for likely biases, and forecast the likely range of outcomes. For example, some methods use different assumptions about the numbers to make different forecasts and then watch the outcomes to judge which assumptions were likely right or wrong. Moreover, those approaches can tell us what data is the most important to collect (hint: it's early and repeated testing to determine whether the disease is in the community, how fast it is spreading, who is getting it, who is spreading it, etc.).

As bad as models are, they beat the alternatives six ways from Sunday.

[bertwert]

reportedly Einstein had problems with simple math

That is simply untrue.

This rumour could be founded on the fact that he did not pass the entrance exam to the Zurich Polytechnic school. Not only was he younger than the average applicant, but he did perfectly fine in maths and physics, but not so well in the other subjects - especially since the exam was in French, rather than German.

[aslyfox]

That is simply untrue.

This rumour could be founded on the fact that he did not pass the entrance exam to the Zurich Polytechnic school. Not only was he younger than the average applicant, but he did perfectly fine in maths and physics, but not so well in the other subjects - especially since the exam was in French, rather than German.

I did say " reportedly "

[Dartmoor Dave]

A "theory" is a point-of-view, a perspective, on a set of facts. A means of organizing the data into a way of seeing the data that allows a more comprehensive understanding. As such, a theory can neither be "true" nor "false", since it's merely a mental construct, like a "worldview". A way of seeing things. Its value is in its utility in making testable hypotheses about gaps in the data, interrelationships, and causality. Theory is to science as opinion is to defamation.

I'm afraid you've got that back to front. Hypotheses come before theories, as explained by Karl Popper in "The Logic of Scientific Discovery", which is the foundation text for most modern understandings of the scientific method.

A hypothesis is our best educated guess based on what's known so far, and crucially it has to experimentally testable in a way that might prove it wrong.

After the hypothesis has been thoroughly tested, and the testing methods themselves have been tested and re-tested, it becomes a theory if it has survived all attempts to prove it wrong. That doesn't mean it's the truth. It means that it's the closest we can get to the truth at the moment using the experimental methods presently available to us, but we always allow for the possibility that new evidence might turn up tomorrow that proves the theory wrong.

The crucial thing is that the hypothesis has to be falsifiable. It has to be testable in a way that might possibly prove it wrong, and only after passing every test we can throw at it does the hypothesis become a theory. A hypothesis that cannot possibly be falsified by any test is meaningless.

When we use the term "scientific fact", what we mean is a theory that has been so thoroughly tested that the chances of it turning out to be wrong are vanishingly small.

[aslyfox]

Catholic/Evangelic Easter is this weekend, and I hope people don't decide to use the holidays (at least Italy, Spain and Germany have two national non-working days each around the weekend) to be reckless.

the Hajj is also a worry

(CNN)Here's a look at Hajj, an annual pilgrimage to Mecca in Saudi Arabia. More than two million Muslims perform the pilgrimage annually.

Facts:
July 28, 2020 - The Hajj pilgrimage is expected to start (dates may vary slightly for different countries depending on the sighting of the New Moon).
. . .

Hajj Pilgrimage Fast Facts - CNN

______________

Hajj pilgrimage could be cancelled because of coronavirus
Saudi authorities pave way for first closure of annual Islamic event in Mecca since 1798

Hajj pilgrimage could be cancelled because of coronavirus | World news | The Guardian

[Serkevan]

the Hajj is also a worry

Hajj Pilgrimage Fast Facts - CNN

Hajj pilgrimage could be cancelled because of coronavirus | World news | The Guardian

Certainly! I left it out because this year it should happen in the middle of summer (just checked and it will be 22nd of July to 19th of August this year).

[luftfluss]

Strange days indeed, when Dave Mustaine is our Mom...

You Tube

You Tube

[Rondec]

Yes, GIGO affects all models, especially forecasting models that combine exponential growth of the virus and inexplicable human behavior.

However, there are a wide range of computational, mathematical, statistical, and scientific approaches that can tackle the problem. They can make the most of the sparse data we do have, account for the uncertainties in that data, correct for likely biases, and forecast the likely range of outcomes. For example, some methods use different assumptions about the numbers to make different forecasts and then watch the outcomes to judge which assumptions were likely right or wrong. Moreover, those approaches can tell us what data is the most important to collect (hint: it's early and repeated testing to determine whether the disease is in the community, how fast it is spreading, who is getting it, who is spreading it, etc.).

As bad as models are, they beat the alternatives six ways from Sunday.

I'm just amazed at how quickly the IHME model is diverging from reality. I'm focused a bit on Virginia since I live here. By that model, there should be 97 deaths and 1051 hospital beds predicted as needed for April 6th. The state website says that currently there have been 54 deaths and 497 hospital stays as the result of COVID in Virginia (not sure if all of those patients are still in the hospital or not). So when the projection varies that much from the reality in just a few days of predicting, it tells me that the long term projections are going to be much worse.

It feels like weather forecasting, where short term forecasting, a few days from now, will be relatively accurate, but anything farther out is a crap shoot.

Maybe the biggest thing is that differences in verbiage in state mandates influence predictions. So, Virginia has not officially close non-essential businesses, but they are pretty much closed at this point. Certainly no more remain open than in states like Kentucky and Ohio where they have officially closed them.

Anyway, I suppose in the end it is probably best that people are scared to minding their distance in the short term if it means that we can get back to normal a little quicker, but it certainly doesn't make me feel good about our ability to predict the future, even in some limited sense.

Psychohistory this ain't...

(I guess we need Hari Seldon about now)...

[luftfluss]

Some hopeful news...

Number of new hospitalizations reported by NY governor Andrew Cuomo:

• Friday, April 3: 1,095
• Saturday, April 4: 574
• Sunday, April 5: 358

[sbh]

That's a lot for one state in one day.

[photoptimist]

I'm just amazed at how quickly the IHME model is diverging from reality. I'm focused a bit on Virginia since I live here. By that model, there should be 97 deaths and 1051 hospital beds predicted as needed for April 6th. The state website says that currently there have been 54 deaths and 497 hospital stays as the result of COVID in Virginia (not sure if all of those patients are still in the hospital or not). So when the projection varies that much from the reality in just a few days of predicting, it tells me that the long term projections are going to be much worse.

It feels like weather forecasting, where short term forecasting, a few days from now, will be relatively accurate, but anything farther out is a crap shoot.

Maybe the biggest thing is that differences in verbiage in state mandates influence predictions. So, Virginia has not officially close non-essential businesses, but they are pretty much closed at this point. Certainly no more remain open than in states like Kentucky and Ohio where they have officially closed them.

Anyway, I suppose in the end it is probably best that people are scared to minding their distance in the short term if it means that we can get back to normal a little quicker, but it certainly doesn't make me feel good about our ability to predict the future, even in some limited sense.

Psychohistory this ain't...

(I guess we need Hari Seldon about now)...

Psychohistory this ain't!

The biggest unknowns for forecasting outcomes is: 1) the effect of public policy (and individual action) on the R0 of the virus; 2) the initial true rate of infection in the community. Both could easily create factor-of-2X or 3X errors in outcomes. You can see the effect of that in the IHME forecasts -- the forecast midpoint daily death rate is 60 but it might be as low as 10 or as high as 250.

Even the outcome data is less accurate than it appears for at least two reasons. The first is the quality of reporting -- how many people are being hospitalized right now who have unknown COVID status. When will their test results hit the reported data? Second, I'd also not be surprised if people's (and doctor's) willingness to send people to the hospital has dropped. If patients fear the quality of care in an over-crowded hospital or doctors subconsciously ration treatment for people who "aren't too sick," then a smaller than usual percentage of COVID-infected people will be hospitalized.

Hopefully, the margins of errors on the forecasts will decline. More hopefully, the rates of disease and death will decline!

[Unregistered User 8]

British Prime Minister Boris Johnson's health has deteriorated and he has been moved to intensive care.
Fingers crossed for him and his family.

[Fluegel]

The virus does not discriminate. Everybody has a chance to catch it.

[Unregistered User 8]

The virus does not discriminate.

Agreed.

Everybody has a chance to catch it.

Some more than others though. Failing to adhere to social distancing advis(c)e and continuing to shake hands raises ones chances greatly.