COVID-19 short-term forecasts Confirmed 2020-04-09


Disclaimer

  • Forecasts produced by Jennie Castle, Jurgen Doornik, and David Hendry, researchers at the University of Oxford. These are our forecasts, and should not be considered official forecasts from, or endorsed by, any of: University of Oxford, Oxford Martin School, Nuffield College, or Magdalen College.
  • These forecasts are short term time-series extrapolations of the data. They are not based on epidemiological modelling or simulations. The documentation that is provided is still in progress and not peer reviewed. All forecasts are uncertain: their success can only be determined afterwards. Many mitigation strategies are in place, which, if successful, invalidate our forecasts. An explanation of our methods is provided below.

Recent changes

[2020-03-24] Our forecasts are starting to overestimate in some cases. This was always expected to happen when the increase starts to slow down. Scenario forecasts that are based on what happened in China earlier this year, but only for Italy and Spain sofar.
[2020-03-26] Scenario forecasts that are based on what happened in China earlier this year, only for Italy.
[2020-03-31] Scenario forecasts, based on what happened in China earlier this year, are presented for several countries (line marked with x). Created more plausible 90% confidence bands (dotted line in same colour).
[2020-04-02] Now including more US States, based on New York Times data. And the world.
[2020-04-06] Added a post hoc estimate of the peak number of cases. This needs at least three confirmed observations (four for deaths) after the event. It is based on the averaged smooth trend, and can change later or be a local peak. It is marked with a vertical line with the date label, or a date with left arrow in the bottom left corner of the graph. This is backported to 2020-04-04.
[2020-04-08] Minor correction to peak estimates. Added table with scenario forecasts.
[2020-04-09] Added table with estimated peak dates (if happened) and dates to and since the peak. Note that this can be a local peak, and subsequent re-acceleration (or data revisions) can result in a new peak later.
[2020-04-10] Updated documentation with better description of short-term estimates and peak determination.

Further information

  • We believe these forecasts fill a useful gap in the short run. They give an indication of what is likely to happen in the next few days, removing some aspect of surprise. Moreover, a noticeable drop in comparison to the extrapolations could be an indication that the implemented policies are having some impact. It is difficult to understand exponential growth. We hope that these forecasts may help to convince viewers to adhere to the policies implemented by their respective governments, and keep all arguments factual and measured.
  • We use the data repository for the 2019 Novel Coronavirus Visual Dashboard operated by the Johns Hopkins University Center for Systems Science and Engineering. This is updated daily, but we tend to update our forecasts only every other day.
    US state data as of 2020-03-28 is courtesy of the New York Times.
  • We can only provide forecasts of what is measured. If confirmed cases are an underestimate of actual cases, then our forecasts will also be underestimates. No other epidemiological data is used.
  • We will update the methodology as we learn what is happening in the next few days or weeks. Once the number of cases levels off, there is no need to provide these forecasts anymore.
  • Countries where the counts are very low or stable have been omitted.
  • The graphs have dates on the horizontal axis (yyyy-mm-dd) and cumulative counts on the vertical axis. They show
    1. bold dark grey line (with circles): observed counts (Johns Hopkins CSSE);
    2. many light grey lines (with open circles): forecasts using different model settings and starting up to four periods back;
    3. red line (with open circles): single forecasts path using default model settings;
    4. black line (with crosses): average of all forecasts, recentered on the last observation;
    5. thin green lines: some indication of uncertainty around the red forecasts, but we do not know how reliable that is.
    Both the red line forecasts and the black lines are also given in the tables above. These forecasts differ, we are currently inclined to use the average forecasts.
  • The forecasts are constructed as follows:
    1. An overall `trend' is extracted by taking a window of the data at a time. In each window we draw `straight lines' which are selected using an automatic econometric procedure (`machine learning'). All straight lines are collected and averaged, giving the trend.
    2. Forecasts are made using the estimated trend, but we note that this must be done carefully, because simply extrapolating the flexible insample trend would lead to wildly fluctuating forecast. We use the `Cardt' method, which has been found to work well in other settings.
    3. Residuals from the trend are also forecast, and combined with trend forecasts into an overall forecast.
  • Scenario forecasts are constructed very differently: smooth versions of the Chinese experience are matched at different lag lengths with the path of each country. This probably works best from the peak, or the slowdown just before (but we include it for the UK nonetheless).
  • The forecast evaluation shows past forecasts, together with the outcomes (in the grey line with circles).
  • EU-BS is Estonia, Latvia, and Lithuania together.
  • This paper describes the methodology and gives further references, but remains preliminary. Also preliminary is the documentation of the medium term forecasts.

Confirmed count average forecast Europe (bold black line in graphs) 2020-04-10 to 2020-04-14

DateUKEUATBEBSCZDEDKESFIFRIEITNLPLPTROSENOCH
2020-04-09 65077 660576 13244 24983 5277 5569 118181 5635 153222 2605 117749 6574 143626 21762 5575 13956 5202 9141 6211 24051
2020-04-10 71000 687000 13500 26700 5420 5810 123000 5970 158000 2810 125000 7070 147000 23100 6040 14600 5600 9900 6320 24800
2020-04-11 78000 714000 13800 28600 5570 6050 127000 6350 163000 3030 136000 7630 151000 24600 6570 15200 5980 10600 6460 25500
2020-04-12 86000 742000 14000 30600 5730 6290 131000 6750 168000 3280 147000 8230 155000 26100 7140 15800 6390 11400 6610 26100
2020-04-13 94000 770000 14300 32800 5890 6550 135000 7180 173000 3550 159000 8880 159000 27800 7760 16400 6830 12300 6750 26800
2020-04-14 104000 798000 14600 35200 6050 6810 139000 7640 179000 3840 173000 9580 163000 29700 8440 17100 7300 13200 6900 27500

Confirmed count average forecast (bold black line in graphs) 2020-04-10 to 2020-04-14

DateAustraliaBrazilCanadaIranMalaysiaPhilippinesUSUS-CAUS-COUS-CTUS-FLUS-GAUS-ILUS-LAUS-MAUS-MIUS-NJUS-NYUS-WAWorld
2020-04-09 6108 18092 20654 66220 4228 4076 461437 20191 6202 9784 16819 10885 16422 18283 18941 21375 51027 159937 9608 2167153
2020-04-10 6200 20200 22200 68000 4380 4230 505000 21600 6650 10900 17900 12000 18100 19600 21000 22900 54500 172000 10000 2309000
2020-04-11 6310 22300 24000 70000 4540 4410 561000 23100 7120 11900 19100 13200 20000 21200 23100 24700 58300 188000 10500 2473000
2020-04-12 6410 24600 26000 72000 4720 4600 623000 24800 7630 13200 20300 14600 22200 23000 25500 26600 62300 204000 11000 2648000
2020-04-13 6510 27200 28100 74000 4900 4790 692000 26600 8180 14500 21600 16100 24600 25000 28200 28600 66600 222000 11500 2832000
2020-04-14 6600 30000 30500 76100 5080 4990 770000 28500 8780 16000 22900 17700 27400 27100 31100 30800 71100 242000 12000 3027000

Confirmed count forecast Europe (bold red line in graphs) 2020-04-10 to 2020-04-14

DateUKEUATBEBSCZDEDKESFIFRIEITNLPLPTROSENOCH
2020-04-09 65077 660576 13244 24983 5277 5569 118181 5635 153222 2605 117749 6574 143626 21762 5575 13956 5202 9141 6211 24051
2020-04-10 69500 684000 13500 27000 5400 5760 122000 5940 158000 2890 125000 7110 147000 23200 6090 14400 5560 10000 6330 24700
2020-04-11 74800 709000 13800 29300 5520 5980 127000 6240 162000 3140 131000 7690 151000 24800 6610 15000 5960 11000 6440 25300
2020-04-12 80400 733000 14000 31700 5640 6210 131000 6560 166000 3410 138000 8320 154000 26400 7150 15700 6370 12000 6560 26000
2020-04-13 86500 757000 14300 34400 5760 6450 135000 6890 171000 3710 145000 9010 158000 28300 7740 16300 6820 13100 6670 26600
2020-04-14 93200 781000 14500 37300 5890 6690 140000 7240 175000 4030 152000 9760 161000 30200 8380 17000 7290 14300 6790 27300

Confirmed count forecast (bold red line in graphs) 2020-04-10 to 2020-04-14

DateAustraliaBrazilCanadaIranMalaysiaPhilippinesUSUS-CAUS-COUS-CTUS-FLUS-GAUS-ILUS-LAUS-MAUS-MIUS-NJUS-NYUS-WAWorld
2020-04-09 6108 18092 20654 66220 4228 4076 461437 20191 6202 9784 16819 10885 16422 18283 18941 21375 51027 159937 9608 2167153
2020-04-10 6200 20000 21900 67900 4360 4180 504000 21400 6800 10700 17700 11800 17900 19200 21100 22500 53800 174000 10000 2320000
2020-04-11 6290 22100 23300 69500 4500 4330 553000 22800 7500 11800 18700 12800 19500 20200 23600 23700 57000 190000 10500 2472000
2020-04-12 6370 24500 24900 71100 4640 4460 609000 24200 8300 13100 19700 13900 21300 21200 26400 25000 60200 207000 10900 2632000
2020-04-13 6460 27100 26500 72700 4790 4600 672000 25700 9100 14400 20800 15100 23200 22300 29500 26200 63500 226000 11400 2797000
2020-04-14 6540 30000 28200 74300 4930 4750 744000 27300 10100 15900 21900 16300 25300 23300 33000 27500 66900 246000 11900 2971000

Confirmed count scenario forecast (bold green line in graphs) 2020-04-10 to 2020-04-18

DateUKEUATBEDEDKESFRITNLPLPTNOCHUS-WAAustraliaIranMalaysia
2020-04-09 65077 660576 13244 24983 118181 5635 153222 117749 143626 21762 5575 13956 6211 24051 9608 6108 66220 4228
2020-04-10 67700 681000 13500 26000 121000 5850 158000 123000 147000 22300 5800 14400 6380 24600 9900 6220 68300 4340
2020-04-11 70600 703000 13700 27400 125000 6070 163000 127000 150000 23200 6030 14800 6530 25100 10200 6330 70100 4450
2020-04-12 73600 724000 14000 28600 128000 6310 168000 129000 152000 24000 6250 15300 6680 25700 10500 6450 72000 4540
2020-04-13 76800 744000 14200 29600 132000 6510 172000 130000 155000 24700 6490 15800 6830 26200 10800 6570 73900 4620
2020-04-14 79300 764000 14500 30400 135000 6680 177000 130000 158000 25400 6710 16300 6980 26800 11100 6700 75700 4710
2020-04-15 81400 782000 14800 31800 138000 6860 181000 131000 161000 26000 6860 16800 7110 27400 11400 6850 77600 4800
2020-04-16 83400 800000 15200 33100 140000 7030 186000 132000 164000 26700 6980 17200 7260 27800 11700 7020 79400 4890
2020-04-17 85800 817000 15400 34400 143000 7200 190000 134000 167000 27300 7130 17700 7410 28300 12000 7160 81400 4990
2020-04-18 88500 836000 15700 35600 146000 7390 194000 136000 170000 27900 7300 18200 7550 28800 12300 7280 83100 5090

Peak increase in estimated trend of Confirmed in Europe 2020-04-09

UKEUATBEBSCZDEDKESFIFRIEITNLPLPTROSENOCH
Peak date --04-0403-26 --03-2503-2703-28 --03-27 -- -- --03-21 -- --03-31 -- --03-2703-23
Peak daily increment 32421 877 285 283 5971 8112 5705 841 299 1205
Days from 100 to peak 41 18 11 14 27 25 27 18 21 18
Days from peak/2 to peak 25 13 11 13 15 14 17 14 19 12
Days since peak 5 14 15 13 12 13 19 9 13 17

Peak increase in estimated trend of Confirmed 2020-04-09

AustraliaBrazilCanadaIranMalaysiaPhilippinesUSUS-CAUS-COUS-CTUS-FLUS-GAUS-ILUS-LAUS-MAUS-MIUS-NJUS-NYUS-WAWorld
Peak date03-28 --04-0503-3104-0203-31 --04-04 -- --04-03 -- --04-04 --04-0404-03 --04-02 --
Peak daily increment 407 1484 3100 180 351 1333 1182 1816 1662 3817 518
Days from 100 to peak 18 25 35 24 17 27 19 19 17 19 26
Days from peak/2 to peak 14 17 28 25 13 18 13 12 13 12 22
Days since peak 12 4 9 7 9 5 6 5 5 6 7

Initial visual evaluation of forecasts of Confirmed