[Update: This blog contained a series of posts showing the results of my Stupid Simple Model for predicting the number of covid fatalities. I deleted most of them because they're irrelevant now. But the upshot is that the SSM was more accurate than the IHME. The philosophy of the SSM was that the IHME was trying to make predictions based on a number of factors that we just didn't know enough about to be meaningful. From the SSM's perspective, they were therefore just noise, more likely to cause distortions than be helpful, and a better prediction could be made by simply extending overall statistical trends. That is, we assume that, while there is a broad range of potential outcomes, the trends have already seen are at the center of those possibilities. That turned out to be more reliable basis for predicting than assuming that we could make use of truckloads of factors we didn't actually understand. In the end, up to the date for which the SSM had made predictions, it was more accurate than the IHME. ]
As of April 17, the Institute for Health Metrics and Evaluation is predicting 60,308 US COVID-19 deaths by August 4, 2020.[1] (Down from their prediction of 68,841 yesterday, and from a prediction 61,545 for that date made on April 12.)
Essentially, this is a contest between the Stupid-Simple Model (SSM) and the IHME. On April 12, the IHME predicted 61,545 deaths by Aug 4. And on that same day, the SSM predicted more fatalities than that by April 22. And it’s still predicting that. That’s 4 days from now! Who will turn out to be closer to correct?
Below is the recent growth in fatality rates:
2020-04-01: 1.24
2020-04-02: 1.26
2020-04-03: 1.18
2020-04-04: 1.13
2020-04-05: 1.13
2020-04-06: 1.14
2020-04-07: 1.18
2020-04-08: 1.16
2020-04-09: 1.12
2020-04-10: 1.13
2020-04-11: 1.1
2020-04-12: 1.08
2020-04-13: 1.07
2020-04-14: 1.1
2020-04-15: 1.1
2020-04-16: 1.16
2020-04-17: 1.12
For the SSM, I average the last 8 days’ exponential growth and get 1.1059. We then take yesterday’s numbers:
2020-04-17: Deaths: 3,857; Accumulated deaths: 36,773
Finally, we project forward using the SSM, seeing that the SSM anticipates more fatalities by 4 days from now (Apr 22) than the IHME predicts for Aug 4.
2020-04-18: Increase: 4,265 Total: 41,038
2020-04-19: Increase: 4,717 Total: 45,755
2020-04-20: Increase: 5,217 Total: 50,972
2020-04-21: Increase: 5,769 Total: 56,742
2020-04-22: Increase: 6,380 Total: 63,123
2020-04-23: Increase: 7,056 Total: 70,179
2020-04-24: Increase: 7,804 Total: 77,984
2020-04-25: Increase: 8,630 Total: 86,614
2020-04-26: Increase: 9,544 Total: 96,159
2020-04-27: Increase: 10,555 Total: 106,715
2020-04-28: Increase: 11,674 Total: 118,389
2020-04-29: Increase: 12,910 Total: 131,300
2020-04-30: Increase: 14,278 Total: 145,578
2020-05-01: Increase: 15,790 Total: 161,368
[1] https://covid19.healthdata.org/united-states-of-america
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