Archive for May 27th, 2020

If I test positive for COVID, am I infected?

May 27, 2020

The answer may surprise you, and it has big implications for test & trace.

In a prior post, we reported that “Asymptomatics” are not rushing to get tested and provided some subjective reasons why that might be (e.g. no doctor referral, high hassle factor, privacy concerns).

OK, let’s up our game a notch or two and throw some math & economics at the problem.


I’m a fan of “Freakonomics” … the popular call sign for a discipline called Behavioral Economics … the study of the rationality that underlies many seemingly irrational decisions that people sometimes make.

And, in my strategic business analytics course, I used to teach something called Bayesian Inference … a way to calculate probabilities by combining contextual information (called “base rates” or “priors”) with case-specific observations (think: testing or witnessing).

Today, we’ll connect Freakonomics and Bayesian Inference and apply them to the COVID testing situation…


May 27: C-19 Key NATIONAL Data

May 27, 2020

Caution: Under-reporting has been common on weekends, “catching-up” on Mon & Tues

Media reports Memorial Day spikes in cases … stay focused on Daily New Deaths.  This post explains why…

MUST READ: How will we know when we’ve turned the COVID-19 corner?


820 Daily New Deaths Worldometer
> 7-day average 1,234
> Peaked on April 21

226 NY+NJ+CT 28% of US Total


Cumulative Deaths 

IHME Model Cume US Death Projection:
131,967 by Aug. 4  Rev. DOWN 11,390 5/25
click to see C-19 Key STATES DataC-19 Data Reference Guide: ALL STATES and Data Recap: The BOTTOM 39

May 27: C-19 Key STATES Data

May 27, 2020

Total US Deaths = 100,625 305 per Million

NY+NJ+CT = 44,500  44% of US Total
   NY+NJ+CT = 10% U.S. Population

Top 12 Total = 79,430 79% of US Total
  Top 12 Average = 516 Deaths per Million
  Top 12 = 48% of U.S. Population

Bottom 39 Average = 120 Deaths/Million
For details see Data Recap: The BOTTOM 39

State-by-State Data – Top 12
Ohio replaced Indiana in the Top 12 on May 25

click chart to enlarge 

 C-19 Data Reference Guide: ALL STATES