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Fred_Kohlhepp23-Emerald I
23-Emerald I
March 13, 2020
Solved

coronavirus math

  • March 13, 2020
  • 7 replies
  • 35574 views

I recall seeing a number of posts, someone developing the equations for the spread and decay of a disease.  Here we have a direct, practical use for this math.

 

Anybody?

    Best answer by JeffH1

    So here is my SIR model of the novel corona virus outbreak.  It's built in Prime 6.0, but I've attached a PDF for those who don't have the latest version.  I welcome any constructive comments and corrections.  I pray that someone finds something wrong with this model, but fear that it is fairly accurate.  The results are disheartening.

    7 replies

    V
    24-Ruby IV
    ValeryOchkov24-Ruby IV
    24-Ruby IV
    March 13, 2020

    One old Mathcad-sheet

    Epidemic.png

    V
    24-Ruby IV
    ValeryOchkov24-Ruby IV
    24-Ruby IV
    March 13, 2020

    antivirus.png

    D
    DJF16-Pearl
    16-Pearl
    March 15, 2020

    https://www.washingtonpost.com/graphics/2020/world/corona-simulator/  

      

    Any interesting model of infection here.  Maybe one of the animation-minded members would like to reproduce in MC.

      V
      24-Ruby IV
      ValeryOchkov24-Ruby IV
      24-Ruby IV
      March 15, 2020

      If my university is transferred to distance learning (and this is quite likely), then I will develop a digital pandemic double with my students.

        F
        Fred_Kohlhepp23-Emerald IAuthor
        23-Emerald I
        March 15, 2020

        Distance working is a lot easier than it used to be.

         

        I moved my simple model to EXCEL to gain formatting improvement over plotting; there are some interesting things to be learned.

          J
          JeffH116-PearlAnswer
          16-Pearl
          March 25, 2020

          So here is my SIR model of the novel corona virus outbreak.  It's built in Prime 6.0, but I've attached a PDF for those who don't have the latest version.  I welcome any constructive comments and corrections.  I pray that someone finds something wrong with this model, but fear that it is fairly accurate.  The results are disheartening.

            F
            Fred_Kohlhepp23-Emerald IAuthor
            23-Emerald I
            March 25, 2020

            Jeff,

             

            BEAUTIFUL!!

            What a delightful analysis (as an exercise, as a predictor of the situation, you're right--we're in deep sh*t.)

             

            I do have questions:

            • On page 2 you set your population size to a million  (N := 10^6).  On page 7, after we have followed China and set R = 0.5, you calculate a susceptible population of SASD(365 day) = 329.9 M persons.
            • Thought I had another, but I can't remember or find it!

            Your analysis reinforces my (much more basic) efforts; thanks for doing such a beautiful exercise on such a terrible issue.

             

            Fred

              J
              JeffH116-Pearl
              16-Pearl
              March 25, 2020

              Fred,

               

              Initially, I set an arbitrary susceptible population at 1M, just to test that units were processing correctly.  In the actual analysis, at the top of page 5, I start using the actual US population, which is N.us := 330 M.   Following aggressive social distancing (I followed the curves out until the infected level was well below zero) the susceptible population drops to, S.asd(365 days) = 329.9M, or just below the initial susceptible population.

              W
              Werner_E25-Diamond I
              25-Diamond I
              March 27, 2020

              You may also be interested in this Numberphile video.

              The modelling is done "live" on the fly - not using Mathcad, though, but the free GeoGebra.

              https://www.youtube.com/watch?v=k6nLfCbAzgo

               

              V
              24-Ruby IV
              ValeryOchkov24-Ruby IV
              24-Ruby IV
              April 1, 2020

              A type of epidemic is the financial pyramid

              See attachment.

              From book the book 2^5 Problems for STEM education

              FinEpid.png

               

              R
              regcurry16-Pearl
              16-Pearl
              April 1, 2020

              No wonder I never became rich.🤪

              F
              FDS13-Aquamarine
              13-Aquamarine
              April 2, 2020

              Dear Reg, would you mind sharing your corrected MC 15 file? Best regards and stay safe, Filip 

              V
              24-Ruby IV
              ValeryOchkov24-Ruby IV
              24-Ruby IV
              May 2, 2020

              New article

              Comparative analysis of the mathematical models of the dynamics of the coronavirus COVID-19 epidemic development in the different countries 

              F
              Fred_Kohlhepp23-Emerald IAuthor
              23-Emerald I
              May 2, 2020

              Interesting analysis (in your referenced paper.)  But a question that I didn't see answered in the paper: 

              The authors define population sizes {N = S(t)+I(t)+R(t)} for each of their models, but those numbers don't agree in any coherent sense with the country's population.

              FredKohlhepp_0-1588422262364.png

              (If you let me "turn enough knobs" I'll match any trend.  😉

              It is, however, a very interesting discussion:

              Most likely, the reason for the
              outbreak was that at the beginning of the pandemic, the
              United States decided to follow the path of rapid
              immunization, i.e. obtaining collective immunity due to a
              greater number of patients. The decision not to impose total
              quarantine was due to concerns about the economy.

               

              Those of us sitting in the middle of this debacle would put a different spin on it, your authors were kind enough to assign at least a conscious choice to our federal government.

               

              It is interesting that the percentages of your paper's populations are so low compared to the actual populations.  There are at least four studies that demonstrate that a significant number of people are infected and can transmit the virus but display few or no symptoms, are "unsymptomatic."  Two of these studies claim that 50% of the people shown to be infected have no symptoms.  With that in mind I built (yet another) model to address that.  All of my models to date result in much higher rates of infection until I set the symptomatic percentage of the population to a very low (1.67%) value.  A rough working copy of this latest model (in Prime 4) is attached.  Data from the USA is embedded and compared.  The effects of "social distancing" are included.  And the possible repercussions of relaxing that lockdown can be evaluated.

               

              I solicit and appreciate comments and criticisms.

              R
              regcurry16-Pearl
              16-Pearl
              May 2, 2020
              Are you actually blaming the US for the COVID-19 pandemic?👎
              S
              StuartBruff23-Emerald V
              23-Emerald V
              May 2, 2020
              Kudoed for such an interesting and informative thread. Nice one, Fred.

              Cheers,

              Stuart
              V
              24-Ruby IV
              ValeryOchkov24-Ruby IV
              24-Ruby IV
              May 2, 2020

              Covid.png

                F
                Fred_Kohlhepp23-Emerald IAuthor
                23-Emerald I
                May 3, 2020

                A businessman went looking for an accountant.  As a test of ability he asked each candidate to calculate his annual tax (based on income.)

                 

                Candidate #1 said, "You owe $20,000.00"

                 

                Candidate #2 said, "He's wrong, you owe $12,000.00"

                 

                Candidate #3 said, "How much do you want to owe?"

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