Skip to main content

COVID-19 Case Fatality Rate

Researchers are hard at work to determine all facets of COVID-19 (https://ourworldindata.org/coronavirus for example). I'm no expert, but I just wanted to play with some data a bit and see what I got. I do sort of thing a lot, and decided to share.

This is a quick attempt at estimating the COVID-19 mortality rate / case fatality rate (number of people who die from it over number of people who got it). That's not the only important number, and can vary from place to place given appropriate medical attention, etc. But I ran across this tweet: No photo description available.
and I was curious about what story that data might tell us.

Disclaimer up front. There's a lot we don't know as of this writing (March 16, 2020) about COVID-19. There may very well be people who have it without symptoms or who have otherwise not been tested. People who have it now may die from it. People who have it now may recover from it. There's a lot of uncertainty.

Also, disclaimer, I'm having a little trouble verifying those numbers in the tweet (also some of the percentages don't quite match the fatalities and cases listed in parentheses). But I'll run with them for now, as they seem at least close to values here: https://ourworldindata.org/coronavirus.

A simple model

Again, work is ongoing in this area by subject-matter experts (which I am not). But current case-fatality rate estimates seem to be somewhere between 0.25%-3.0% (https://wwwnc.cdc.gov/eid/article/26/6/20-0320_article#r7).

I wanted a simple model that assumes that the error in case-fatality rate is exponentially decaying. That's a simple way to model having an actual rate that things are slowly approaching. Again, lots of reasons that might not be true.

Using those values in the tweet, I got the following:
This simple model thus implies the case-fatality rate is something like 0.63%. That's well within the feasible values in the CDC research paper above. And in fact, after correcting the Diamond Princess cruise ship data for age (https://wwwnc.cdc.gov/eid/article/26/6/20-0320-t1) is exactly the case-fatality rate the researchers got in that paper.

Anyway, in lieu of some final profound insight, go wash your hands.

Comments

  1. nadaMarch 17, 2020 at 12:15 PM

    This comment has been removed by a blog administrator.

    ReplyDelete

Post a Comment

Popular posts from this blog

The Cereal Box Prize Distribution

In October 2015, General Mills introduced a line of Star Wars  prizes in some of their cereal boxes. Much like the boy who asked, "Mr. Owl, how many licks does it take to get to the Tootsie Roll center of a Tootsie Pop?" I wanted to know: How many boxes of cereal do I need to buy to get all the prizes? If you looked at the image, screamed "6!" at your screen, and wondered why there are additional sections to this post, let me clarify: we don't know what prize is inside until we open the box. It's random. Now, we're in statistics country. In statistics, we're all about distributions . That is, models that say how likely something is. You're probably familiar with at least one, the normal distribution (a.k.a. the Gaussian distribution, a.k.a. the bell curve). If we think about GPA, the normal distribution says (if the average is a C), that C would be in the middle, which is also the most common. A would be far out to th...
2 comments
Read more

Programmatic Thinking and the Google Doodle

There's a joke (or as my former professor might have said, "it's like a joke, it just lacks humor") about how programmers think: Programmer: "How do I make pasta?" Recipe: How to make pasta: Fill an empty pot with cold water Boil it Add pasta Programmer goes home and wants to make pasta. She sees a pot of boiling water already on the stove. So she pours it out, fills it up with cold water, boils it, then adds pasta. Again, like a joke, but potentially lacks humor. For those not "in the know," the joke is that programmers tend to reduce problems to ones they've already solved. In this case, the programmer already had a solution for making pasta. So, she changed things around until she could use it. In this case, we end up doing more work than necessary, but in general, this can be extremely effective. This week, the Google Doodle is pretty great. It's a coding game geared toward kids, in the same vein as Scratch or...
Post a Comment
Read more