
Keeping score of forecasts is the key to assessing and improving your forecast accuracy. Here we show how it is done.
As the covid-19 pandemic hit the United States, we were invited to submit forecast estimates alongside a CDC-funded panel of experts in public health. Our forecasts have been more accurate than virus experts despite having no training in public health, virology, or epidemiology. We simply follow the same sound forecasting techniques that we teach to our clients.
Below you can see a complete record of our coronavirus forecasts.
Forecast (10%-90% interval) |
Accuracy Score (Brier score) |
|||||
wk | Question | TOM | EXPERTS | Outcome | TOM | EXPERTS |
AVERAGE BRIER SCORE (green is better, red is worse) |
0.246 | 0.268 | ||||
5/10 | How many deaths will Pennsylvania report as of June 13? (in thousands) |
7.6 (5.2-12) |
7.2 (5.2-10) |
6.2 | 0.214 | 0.180 |
5/10 | How many confirmed US cases will there be on May 17? (in millions) |
1.48 (1.45-1.57) |
1.5 (1.47-1.6) |
1.48 | 0.062 | 0.135 |
5/10 | How many cases per day will Washington state average for the week ending June 7? |
170 (30-500) |
331 (158-644) |
155 | 0.289 | 0.713 |
5/3 | How many confirmed US cases will there be on May 10? (in millions) |
1.33 (1.27-1.39) |
1.35 (1.25-1.44) |
1.33 | 0.066 | 0.129 |
5/3 | What will the 7 day average new cases be in Texas for the week ending June 13? |
1150 (400-3000) |
1350 (750-2300) |
1779 | 0.323 | 0.166 |
5/3 | How many US states/territories will report more new cases for September compared to June? |
7 (1-42) |
21 (2-45) |
45 | 1.088 | 0.660 |
5/3 | How many US COVID deaths will occur in 2020? (in thousands) |
160 (90-800) |
256 (118-1212) |
345 | 0.256 | 0.180 |
4/26 | How many confirmed US cases will there be on May 3? (in millions) |
1.14 (1.09-1.21) |
1.14 (1.07-1.24) |
1.152 | 0.174 | 0.195 |
4/26 | When will weekly new US deaths first fall below 5,000 (Sunday to Saturday)? |
5/23 (5/9-6/26) |
6/13 (5/16-7/4) |
6/20 | 0.376 | 0.158 |
4/26 | What will the average new daily cases be for Georgia between 5/10 and 5/16 inclusive? |
900 (150-5000) |
1044 (579-2292) |
659 | 0.159 | 0.173 |
4/19 | How many deaths due to COVID-19 will occur in the US in 2020? (in thousands) |
80 (48-750) |
150 (72-517) |
345 | 0.537 | 0.170 |
4/19 | How many confirmed US cases will there be on April 26? (in thousands) |
930 (870-990) |
950 (860-1060) |
959 | 0.222 | 0.127 |
4/19 | As of May 9, how many COVID-19 related deaths will have occurred in Louisiana? (in thousands) |
1.85 (1.55-3.4) |
2.8 (1.85-5.0) |
2.2 | 0.129 | 0.170 |
4/19 | As of May 9, how many COVID-19 related deaths will have occurred in the US? (in thousands) |
56 (47-77) |
70 (51-106) |
73 | 0.420 | 0.170 |
4/19 | As of May 9, how many COVID-19 related deaths will have occurred in Illinois? (in thousands) |
2.4 (1.7-4.8) |
2.8 (1.8-5.2) |
3.3 | 0.294 | 0.170 |
4/12 | How many states will report more than 1000 deaths by May 1? |
12 (9-16) |
9 (4-15) |
14 | 0.193 | 0.712 |
4/12 | How many US COVID-19 deaths will occur by June 1? (in thousands) |
71 (48-127) |
71 (45-131) |
99 | 0.178 | 0.180 |
4/12 | Which of the next 6 months will see the highest total number of deaths nationwide in the US for COVID-19 illness? |
April (April-June) |
April (March-July) |
April | 0.037 | 0.108 |
4/12 | How many US COVID-19 deaths will occur by May 1? (in thousands) |
50 (36-66) |
46 (34-68) |
59 | 0.111 | 0.180 |
4/12 | How many US COVID-19 cases will there be on April 19? (in thousands) |
755 (710-795) |
780 (690-905) |
751 | 0.093 | 0.151 |
4/5 | Which month (March-August) will see the highest total number of hospitalizations nationwide in the US for COVID-19 illness? |
April (April-June) |
May (April-August) |
April | 0.043 | 0.370 |
4/5 | How many US COVID-19 cases will there be on April 12? (in thousands) |
520 (470-680) |
670 (510-900) |
551 | 0.103 | 0.336 |
3/29 | Which month (March-August) will see the highest total number of hospitalizations nationwide in the US for COVID-19 illness? |
April (April-June) |
May (April-August) |
April | 0.137 | 0.344 |
3/29 | Will NY state report fewer than 1,000 new cases on the day of April 28? |
28% (-) |
50% (-) |
no | 0.157 | 0.500 |
3/29 | How many US COVID-19 cases will there be on April 5? (in thousands) |
410 (250-590) |
420 (260-580) |
332 | 0.123 | 0.145 |
3/29 | How many deaths due to COVID-19 will occur in the US in 2020? (in thousands) |
240 (75-1200) |
260 (80-1000) |
345 | 0.244 | 0.212 |
3/22 | Will US COVID-19 deaths exceed 245,500 by the end of 2020? (percent probability YES) |
45% (-) |
50% (-) |
345k | 0.605 | 0.500 |
3/22 | Will there will be a second wave of US cases in 2020? (US active cases declines by 50% and subsequently increases by 50% AND 2nd wave must be at least 50% as high) (probability YES) |
52% (-) |
73% (-) |
VOID |