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It is now 563 days since the first COVID-19 case was reported in Nigeria. As at September 13, 2021 the confirmed cases are 200,491 with 2,619 (1.31%) fatalities, however, 188,427 (94.43%) have recovered leaving 8,492 (4.26%) active cases.

Based on equal days forecast, by March 30, 2023, Nigeria’s aggregate confirmed COVID-19 cases are forecast to be:

Unconstrained forecast of COVID-19 for Nigeria

Model Confirmed cases Recoveries Fatalities Active RMSE
With knots 1,827,374 1,725,589 23,939 77,846 157
Upper ARIMA 1,373,444 1,296,943 17,992 58,509 139
Without knots 446,360 421,498 5,847 19,015 373
Linear 285,695 269,782 3,743 12,171 367
Semilog 275,196 259,868 3,605 11,723 139
Essembled based on weight 230,722 217,871 3,022 9,829 388
Essembled with equal weight 219,645 207,411 2,877 9,357 272
Essembled based on weight of fit 175,520 165,744 2,299 7,477 1.6
Growth 3,490 3,296 46 149 162
Essembled based on summed weight -80,806 -76,306 -1,059 -3,442 381
Quadratic Polynomial -247,231 -233,460 -3,239 -10,532 200
Lower ARIMA -879,781 -830,777 -11,525 -37,479 133
Smooth Spline -1,489,237 -1,406,287 -19,509 -63,442 157

Constrained forecast of COVID-19 for Nigeria

Model Confirmed cases Recoveries Fatalities Active
ARIMA 95% 1,358,800 1,283,114 17,800.0 57,885
Without knots 95% 1,322,744 1,249,067 17,328.0 56,349
Essembled based on weight 95% 1,317,091 1,243,729 17,254.0 56,108
Essembled based on summed weight 95% 1,196,228 1,129,598 15,671.0 50,959
Smooth Spline 95% 949,604 896,711 12,440.0 40,453
Essembled with equal weight 95% 907,338 856,799 11,886.0 38,653
Essembled based on weight of fit 95% 691,295 652,790 9,056.0 29,449
Linear 285,695 269,782 3,743.0 12,171
Semilog 275,196 259,868 3,605.0 11,723
With knots 95% 209,277 197,620 2,742.0 8,915
Quadratic Polynomial 95% 93,768 88,545 1,228.0 3,995
Essembled with equal weight 80% 73,719 69,613 966.0 3,140
Quadratic Polynomial 80% 69,597 65,720 912.0 2,965
Essembled based on weight of fit 80% 69,156 65,304 906.0 2,946
Smooth Spline 80% 53,268 50,301 698.0 2,269
Essembled based on summed weight 80% 29,560 27,913 387.0 1,259
Essembled based on weight 80% 12,830 12,115 168.0 547
Without knots 80% 12,194 11,515 160.0 519
ARIMA 80% 6,389 6,034 84.0 272
Growth 3,490 3,296 46.0 149
With knots 80% 2 2 0.0 0

However, the actual forecast made by the various models on the last day i.e. March 30, 2023 is shown below:

Unconstrained forecasts on the last day

Constrained forecasts on the last day

Refer to Table 2 and Table 3 as well as Fig. 18-20 for more details on how the estimates and forecasts were obtained.

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The visuals below supports this facts, take a look!

Fig. 1a Daily observed cases of COVID-19 in Nigeria

Fig. 2 Perecentages and previous days differences of COVID-19 in Nigeria Starting from February 29, 2020 to September 13, 2021

Fig. 3 Cases recorded in percentages Starting from February 29, 2020 to September 13, 2021 (legend as Fig. 2)

Fig. 4 Cumulative cases and Forecast of COVID-19 cases in Nigeria Starting from September 14, 2021 to March 30, 2023

Fig. 4a Components of COVID-19 cases in Nigeria between February 29, 2020 and September 13, 2021

Fig. 5 Number of days since average recorded cases exceeded one in each State

Fig. 6 Daily confirmed Coronavirus cases, by number of the days since 1 first daily case recorded

Fig. 7 Number of days from February 29, 2020 to September 13, 2021 that cases were recorded in the States

Fig. 7a Numbers of States that COVID-19 cases were reported on daily basis

Fig. 7b Forecast of Numbers of States that may still be COVID-19 affected by March 30, 2023

Coefficient estimates for number of states reporting COVID-19 daily

LinearSemilogGrowthSpline without knotsLinear splinesSpline with knotsARIMA
(Intercept)15.510 ****10.580 ****2.566 ****4.068 ****2.807 *   0.097          
(0.535)    (1.493)    (0.055)    (0.899)    (1.582)    (2.283)         
Series-0.007 ****         -0.000 **                                  
(0.002)             (0.000)                                    
log(Series)         0.576 **                                           
         (0.277)                                             
bs(Series, knots = NULL)1                           34.920 ****                       
                           (2.597)                           
bs(Series, knots = NULL)2                           -6.030 ****                       
                           (1.648)                           
bs(Series, knots = NULL)3                           9.421 ****                       
                           (1.419)                           
bs(DDPtable$Series, knots = c(30, 115, 247, 337, 420))1                                    -2.680                   
                                    (2.256)                  
bs(DDPtable$Series, knots = c(30, 115, 247, 337, 420))2                                    13.685 ****              
                                    (1.673)                  
bs(DDPtable$Series, knots = c(30, 115, 247, 337, 420))3                                    22.948 ****              
                                    (1.950)                  
bs(DDPtable$Series, knots = c(30, 115, 247, 337, 420))4                                    -1.000                   
                                    (1.729)                  
bs(DDPtable$Series, knots = c(30, 115, 247, 337, 420))5                                    29.435 ****              
                                    (1.770)                  
bs(DDPtable$Series, knots = c(30, 115, 247, 337, 420))6                                    -12.723 ****              
                                    (1.857)                  
bs(DDPtable$Series, knots = c(30, 115, 247, 337, 420))7                                    12.776 ****              
                                    (1.960)                  
bs(DDPtable$Series, knots = c(30, 115, 247, 337, 420))8                                    13.417 ****              
                                    (1.824)                  
bs(Series, knots = c(30, 247, 420))1                                             4.784 *        
                                             (2.818)         
bs(Series, knots = c(30, 247, 420))2                                             25.225 ****     
                                             (2.420)         
bs(Series, knots = c(30, 247, 420))3                                             9.860 ****     
                                             (2.795)         
bs(Series, knots = c(30, 247, 420))4                                             20.452 ****     
                                             (2.524)         
bs(Series, knots = c(30, 247, 420))5                                             -3.979          
                                             (2.656)         
bs(Series, knots = c(30, 247, 420))6                                             24.088 ****     
                                             (2.606)         
ma1                                                      -0.753 
                                                      (0.028)
nobs545         545         545         545         545         545         544     
r.squared0.029     0.008     0.010     0.307     0.758     0.453          
adj.r.squared0.027     0.006     0.008     0.303     0.754     0.446          
sigma6.239     6.307     0.637     5.282     3.136     4.707     3.202 
statistic16.326     4.333     5.376     79.817     209.737     74.134          
p.value0.000     0.038     0.021     0.000     0.000     0.000          
df1.000     1.000     1.000     3.000     8.000     6.000          
logLik-1770.119     -1776.026     -526.578     -1678.333     -1391.685     -1613.997     -1404.933 
AIC3546.239     3558.052     1059.156     3366.666     2803.370     3243.994     2813.866 
BIC3559.141     3570.954     1072.058     3388.170     2846.378     3278.400     2822.464 
deviance21136.571     21599.707     220.369     15092.144     5271.182     11918.340          
df.residual543.000     543.000     543.000     541.000     536.000     538.000          
nobs.1545.000     545.000     545.000     545.000     545.000     545.000     544.000 
**** p < 0.001; *** p < 0.01; ** p < 0.05; * p < 0.1.

Properties of the estimated coefficients

Linear Semilog Growth Spline with knots Linear splines Spline without knots Smooth spline ARIMA
Absolute Error 2800 2900 6100 2100 1300 2400 1100 1300
Absolute Percent Error 440 420 420 230 140 280 120 130
Accuracy 0 0 0 0 0 0 0 0
Adjusted R Square 0.027 0.0061 0.008 0.45 0.75 0.3 0 0
Akaike’s Information Criterion AIC 3500 3600 1100 3200 2800 3400 0 2800
Allen’s Prediction Sum-Of-Squares (PRESS, P-Square) 0 0 0 0 0 0 0 0
Area under the ROC curve (AUC) 0.87 0.13 0.87 0.033 0.049 0.022 0.015 0.028
Average Precision at k 0 0 0 0 0 0 0 0
Bias -0.00000000000000096 0.00000000000000074 11 -0.00000000000000038 0.000000000000000011 -0.0000000000000000078 0.0000000000000063 0.099
Brier score 40 40 200 20 10 30 8 10
Classification Error 1 1 1 1 1 1 1 1
F1 Score 0 0 0 0 0 0 0 0
fScore 0 0 0 0 0 0 0 0
GINI Coefficient 0.2 -0.2 0.2 0.7 0.9 0.6 0.9 0.9
kappa statistic 0 0 0 0 0 0 0 0
Log Loss Inf Inf Inf Inf Inf Inf Inf Inf
Mallow’s cp 2 2 2 7 9 4 0 0
Matthews Correlation Coefficient 0 0 0 0 0 0 0 0
Mean Log Loss Inf Inf Inf Inf Inf Inf Inf Inf
Mean Absolute Error 5.2 5.3 11 3.8 2.3 4.4 2.1 2.4
Mean Absolute Percent Error 0.8 0.78 0.77 0.41 0.26 0.52 0.21 0.24
Mean Average Precision at k 0 0 0 0 0 0 0.17 0
Mean Absolute Scaled Error 1.8 1.9 4 1.3 0.83 1.5 0.73 0.85
Median Absolute Error 4.9 5.1 12 3.3 1.9 4 1.6 2
Mean Squared Error 39 40 160 22 9.7 28 7.8 10
Mean Squared Log Error 0.32 0.31 2 0.15 0.075 0.19 0.052 0.069
Model turning point error 328 295 328 304 302 308 306 403
Negative Predictive Value 0 0 0 0 0 0 0 0
Percent Bias -0.55 -0.52 0.72 -0.2 -0.1 -0.3 -0.081 -0.069
Positive Predictive Value 0 0 0 0 0 0 0 0
Precision NaN NaN NaN NaN NaN NaN NaN NaN
R Square 0.029 0.0079 0.0098 0.45 0.76 0.31 0 0
Relative Absolute Error 0.97 1 2.1 0.71 0.44 0.82 0.39 0.45
Recall 15 12 2.5 3 3.4 5.9 2.6 2.2
Root Mean Squared Error 6.2 6.3 13 4.7 3.1 5.3 2.8 3.2
Root Mean Squared Log Error 0.56 0.56 1.4 0.38 0.27 0.43 0.23 0.26
Root Relative Squared Error 0.99 1 2 0.74 0.49 0.83 0.44 0.51
Relative Squared Error 0.97 0.99 4.1 0.55 0.24 0.69 0.19 0.26
Schwarz’s Bayesian criterion BIC 3600 3600 1100 3300 2800 3400 0 2800
Sensitivity 0 0 0 0 0 0 0 0
specificity 0 0 0 0 0 0 0 0
Squared Error 21000 22000 90000 12000 5300 15000 4200 5600
Squared Log Error 170 170 1100 79 41 100 29 37
Symmetric Mean Absolute Percentage Error 0.42 0.44 1.3 0.32 0.22 0.37 0.19 0.21
Sum of Squared Errors 21000 22000 90000 12000 5300 15000 4200 5600
True negative rate 0 0 0 0 0 0 0 0
True positive rate 0 0 0 0 0 0 0 0

Fig. 8 Number of days the last COVID19 case was recorded as at September 13, 2021

Fig. 9 Diverging Bars of COVID-19 cases in the States (normalised)

Fig. 10 Monthly summary of COVID19 cases in the States

Fig. 11 Daily recorded cases of COVID19 in the States

Fig. 12 Number of days since average recorded cases exceeded one in each geo-political zone

Fig. 13 Number of days from February 29, 2020 to September 13, 2021 that cases were recorded in the Zones

Fig. 14 Monthly summary of COVID19 cases in the Zones

Table 1 Regression estimates of factors that might have stressed Nigeria’s economy within the period of the COVID-19 pandemic

COVID19PMSInflationTeledensityBirth ratePopulation
(Intercept)-300.967     -59.196     -225.229     375.635     -35.252 ****15.876 ****
(310.325)    (1845.262)    (201.385)    (428.828)    (7.996)    (0.323)    
PMSprice-0.123 ***          0.100 ****0.196 ****0.002     -0.000     
(0.033)             (0.015)    (0.036)    (0.002)    (0.001)    
Inflation0.998 *** 7.694 ****         -1.499 *** -0.032 **  0.007     
(0.308)    (1.130)             (0.391)    (0.013)    (0.005)    
Teledensity0.604 ****3.437 ****-0.341 ***          -0.002     -0.002     
(0.108)    (0.641)    (0.089)             (0.007)    (0.003)    
`Birth rate`2.537     44.290     -9.390 **  -2.357              0.275 ****
(6.900)    (38.116)    (3.791)    (9.505)             (0.055)    
Population14.578     -21.584     17.124     -16.940     2.320 ****         
(19.754)    (115.754)    (12.382)    (27.288)    (0.467)             
COVID19         -4.059 *** 0.429 *** 1.141 ****0.004     0.003     
         (1.091)    (0.132)    (0.205)    (0.010)    (0.003)    
nobs20         20         20         20         20         20         
r.squared0.739     0.864     0.892     0.818     0.741     0.753     
adj.r.squared0.646     0.815     0.853     0.754     0.648     0.665     
sigma1.309     7.536     0.858     1.798     0.050     0.017     
statistic7.921     17.763     23.007     12.625     8.001     8.526     
p.value0.001     0.000     0.000     0.000     0.001     0.001     
df5.000     5.000     5.000     5.000     5.000     5.000     
logLik-30.199     -65.205     -21.756     -36.551     34.919     56.240     
AIC74.398     144.409     57.513     87.102     -55.839     -98.480     
BIC81.368     151.379     64.483     94.072     -48.868     -91.510     
deviance23.993     794.981     10.314     45.284     0.036     0.004     
df.residual14.000     14.000     14.000     14.000     14.000     14.000     
nobs.120.000     20.000     20.000     20.000     20.000     20.000     
**** p < 0.001; *** p < 0.01; ** p < 0.05; * p < 0.1.

Fig. 15 COVID-19, inflation, PMS price, Teledensity and birth rate in Nigeria

Fig. 15 Relationship between COVID-19, inflation, PMS price, Teledensity and birth rate in Nigeria

Table 2 The coefficient estimates of the various models for forecasting of COVID-19 for Nigeria1

LinearSemilogGrowthSpline without knotsSpline with knotsARIMAQuardratic polynomialEssembled based on weightEssembled based on summed weight
(Intercept)280.308 ****-118.185     4.547 ****-130.898 **  -3.509          41.763     25.806  -1.883     
(32.821)    (89.353)    (0.132)    (61.732)    (62.444)         (47.504)    (148.945) (19.207)    
Day0.269 ***          0.002 ****                       2.802 ****               
(0.101)             (0.000)                           (0.389)                   
log(Day)         88.811 ****                                                        
         (16.458)                                                            
bs(Day, knots = NULL)1                           1228.198 ****                                      
                           (178.364)                                          
bs(Day, knots = NULL)2                           219.535 *                                         
                           (113.183)                                          
bs(Day, knots = NULL)3                           501.988 ****                                      
                           (97.478)                                          
bs(Day, knots = BREAKS)1                                    5.730                                  
                                    (120.718)                                 
bs(Day, knots = BREAKS)2                                    12.469                                  
                                    (78.199)                                 
bs(Day, knots = BREAKS)3                                    844.874 ****                             
                                    (89.645)                                 
bs(Day, knots = BREAKS)4                                    169.101 **                               
                                    (76.161)                                 
bs(Day, knots = BREAKS)5                                    205.045 **                               
                                    (83.423)                                 
bs(Day, knots = BREAKS)6                                    -86.771                                  
                                    (78.502)                                 
bs(Day, knots = BREAKS)7                                    2046.449 ****                             
                                    (78.165)                                 
bs(Day, knots = BREAKS)8                                    -292.551 ****                             
                                    (78.824)                                 
bs(Day, knots = BREAKS)9                                    85.904                                  
                                    (91.572)                                 
bs(Day, knots = BREAKS)10                                    392.347 ****                             
                                    (89.295)                                 
bs(Day, knots = BREAKS)11                                    703.663 ****                             
                                    (81.561)                                 
ar1                                             1.016                         
                                             (0.062)                        
ar2                                             -0.204                         
                                             (0.053)                        
ma1                                             -1.738                         
                                             (0.046)                        
ma2                                             0.815                         
                                             (0.036)                        
I(Day^2)                                                  -0.004 ****               
                                                  (0.001)                   
fitf                                                           0.828  -0.128     
                                                           (7.401) (0.082)    
fit0f                                                           0.020  -0.010     
                                                           (1.037) (0.090)    
fit1f                                                           -0.644  1.286 ****
                                                           (6.216) (0.127)    
fitpif                                                           -0.257  0.010     
                                                           (1.283) (0.102)    
fitaf                                                           0.888  -0.152     
                                                           (5.577) (0.093)    
fitf:fit0f                                                           -0.006           
                                                           (0.023)          
fitf:fit1f                                                           0.024           
                                                           (0.019)          
fit0f:fit1f                                                           0.015           
                                                           (0.025)          
fitf:fitpif                                                           -0.001           
                                                           (0.017)          
fit0f:fitpif                                                           0.001           
                                                           (0.002)          
fit1f:fitpif                                                           -0.011           
                                                           (0.020)          
fitf:fitaf                                                           -0.057           
                                                           (0.035)          
fit0f:fitaf                                                           -0.007           
                                                           (0.019)          
fit1f:fitaf                                                           0.031           
                                                           (0.032)          
fitpif:fitaf                                                           0.012           
                                                           (0.016)          
fitf:fit0f:fit1f                                                           -0.000           
                                                           (0.000)          
fitf:fit0f:fitpif                                                           0.000           
                                                           (0.000)          
fitf:fit1f:fitpif                                                           -0.000           
                                                           (0.000)          
fit0f:fit1f:fitpif                                                           -0.000           
                                                           (0.000)          
fitf:fit0f:fitaf                                                           0.000 *         
                                                           (0.000)          
fitf:fit1f:fitaf                                                           0.000           
                                                           (0.000)          
fit0f:fit1f:fitaf                                                           -0.000           
                                                           (0.000)          
fitf:fitpif:fitaf                                                           0.000           
                                                           (0.000)          
fit0f:fitpif:fitaf                                                           -0.000           
                                                           (0.000)          
fit1f:fitpif:fitaf                                                           -0.000           
                                                           (0.000)          
fitf:fit0f:fit1f:fitpif                                                           0.000           
                                                           (0.000)          
fitf:fit0f:fit1f:fitaf                                                           -0.000           
                                                           (0.000)          
fitf:fit0f:fitpif:fitaf                                                           -0.000 *         
                                                           (0.000)          
fitf:fit1f:fitpif:fitaf                                                           -0.000           
                                                           (0.000)          
fit0f:fit1f:fitpif:fitaf                                                           0.000           
                                                           (0.000)          
fitf:fit0f:fit1f:fitpif:fitaf                                                           -0.000           
                                                           (0.000)          
nobs563         563         563         563         563         562     563         563      563         
r.squared0.013     0.049     0.040     0.116     0.828          0.086     0.884  0.874     
adj.r.squared0.011     0.048     0.038     0.111     0.825          0.083     0.877  0.873     
sigma388.863     381.541     1.560     368.632     163.682     157.544 374.385     137.042  139.532     
statistic7.106     29.119     23.384     24.391     241.403          26.448     130.425  771.076     
p.value0.008     0.000     0.000     0.000     0.000          0.000     0.000  0.000     
df1.000     1.000     1.000     3.000     11.000          2.000     31.000  5.000     
logLik-4155.157     -4144.455     -1048.113     -4124.072     -3662.928     -3639.618 -4133.293     -3552.513  -3576.107     
AIC8316.314     8294.911     2102.226     8258.144     7351.856     7289.236 8274.586     7171.026  7166.213     
BIC8329.314     8307.911     2115.225     8279.811     7408.189     7310.893 8291.919     7314.024  7196.546     
deviance84831112.306     81666701.075     1364.736     75962321.679     14762196.420          78491708.762     9972507.649  10844362.905     
df.residual561.000     561.000     561.000     559.000     551.000          560.000     531.000  557.000     
nobs.1563.000     563.000     563.000     563.000     563.000     562.000 563.000     563.000  563.000     
**** p < 0.001; *** p < 0.01; ** p < 0.05; * p < 0.1.

Table 3 Various selection criteria for the estimated models2

Linears Semilogs Growths Spline with knots Spline without knots Smooth spline ARIMA Quardratic polynomial Essembled equal weight Essembled on weight Essembled summed weight Essembled weight of fit
Absolute Error 160000 160000 200000 60000 150000 44000 51000 160000 200000 44000 44000 200000
Absolute Percent Error Inf Inf Inf Inf Inf Inf Inf Inf Inf Inf Inf Inf
Accuracy 0 0 0 0 0 0 0 0 0.032 0 0 0.032
Adjusted R Square 0.011 0.048 0.038 0.82 0.11 0 0 0.083 0 0.88 0.87 0
Akaike’s Information Criterion AIC 8300 8300 2100 7400 8300 0 7300 8300 0 7200 7200 0
Allen’s Prediction Sum-Of-Squares (PRESS, P-Square) 0 0 0 0 0 0 0 0 0 0 0 0
Area under the ROC curve (AUC) 0.008 0.008 0.008 0.085 0.008 0.008 0.016 0.008 0.008 0.032 0.008 0.008
Average Precision at k 0 0 0 0 0 0 0 0 0.5 0 0 0.5
Bias 0.00000000000000081 0.00000000000001 350 -0.0000000000000022 -0.000000000000034 -0.00000000000043 1.9 0.000000000000032 360 -0.0000000000000019 0.000000000000001 360
Brier score 200000 100000 300000 30000 100000 20000 20000 100000 NaN 20000 20000 NaN
Classification Error 1 1 1 1 1 1 1 1 1 1 1 1
F1 Score 0 0 0 0 0 0 0 0 0 0 0 0
fScore 0 0 0 0 0 0 0 0 0 0 0 0
GINI Coefficient 0.1 0.1 0.1 0.9 0.3 1 0.9 0.5 0.9 1 1 0.9
kappa statistic 0 0 0 0 0 0 0 0 NaN 0 0 NaN
Log Loss Inf Inf Inf Inf Inf Inf Inf Inf Inf Inf Inf Inf
Mallow’s cp 2 2 2 12 4 0 0 3 0 0 6 0
Matthews Correlation Coefficient 0 0 0 0 0 0 0 0 NaN 0 0 NaN
Mean Log Loss Inf Inf Inf Inf Inf Inf Inf Inf NaN Inf Inf NaN
Mean Absolute Error 290 280 350 110 270 78 90 290 NaN 78 79 NaN
Mean Absolute Percent Error Inf Inf Inf Inf Inf Inf Inf Inf Inf Inf Inf Inf
Mean Average Precision at k 0 0 0 0 0 0.5 0 0 0 0 0 0
Mean Absolute Scaled Error 2.8 2.7 3.4 1 2.6 0.75 0.86 2.7 3.4 0.74 0.75 3.4
Median Absolute Error 250 220 210 73 250 35 43 270 110 41 37 150
Mean Squared Error NA NA NA NA NA NA NA NA NaN NA NA NaN
Mean Squared Log Error 3 NaN 13 NaN NaN NaN 0.26 2.4 29 NaN NaN 29
Model turning point error 286 286 286 278 288 271 374 278 344 269 235 341
Negative Predictive Value 0 0 0 0 0 0 0 0 0 0 0 0
Percent Bias -Inf NaN -Inf NaN NaN NaN -Inf -Inf NaN NaN NaN NaN
Positive Predictive Value 0 0 0 0 0 0 0 0 0 0 0 0
Precision NaN NaN NaN NaN NaN NaN NaN NaN 0 NaN NaN 0
R Square 0.013 0.049 0.04 0.83 0.12 0 0 0.086 0 0.88 0.87 0
Relative Absolute Error 0.99 0.96 1.2 0.36 0.92 0.27 0.31 0.98 0.47 0.27 0.27 0.63
Recall 280 -12 4.6 -2.1 -99 -0.2 0.5 58 0 3.8 -0.38 0
Root Mean Squared Error NA NA NA NA NA NA NA NA NaN NA NA NaN
Root Mean Squared Log Error 1.7 NaN 3.7 NaN NaN NaN 0.51 1.5 5.3 NaN NaN 5.3
Root Relative Squared Error 0.99 0.98 1.3 0.41 0.94 0.36 0.4 0.96 1.4 0.34 0.36 1.4
Relative Squared Error 0.99 0.95 1.8 0.17 0.88 0.13 0.16 0.91 1.8 0.12 0.13 1.8
Schwarz’s Bayesian criterion BIC 8300 8300 2100 7400 8300 0 7300 8300 0 7300 7200 0
Sensitivity 0 0 0 0 0 0 0 0 0.5 0 0 0.5
specificity 0 0 0 0 0 0 0 0 0 0 0 0
Squared Error 85000000 82000000 160000000 15000000 76000000 11000000 14000000 78000000 160000000 10000000 11000000 160000000
Squared Log Error 1700 NaN 7500 NaN NaN NaN 150 1300 16000 NaN NaN 16000
Symmetric Mean Absolute Percentage Error 0.89 0.89 1.8 0.58 0.85 0.34 0.4 0.92 0.6 0.38 0.36 0.7
Sum of Squared Errors 85000000 82000000 160000000 15000000 76000000 11000000 14000000 78000000 160000000 10000000 11000000 160000000
True negative rate 0 0 0 0 0 0 0 0 0 0 0 0
True positive rate 0 0 0 0 0 0 0 0 0 0 0 0

Fig. 18 Models of COVID-19 Cases using ensemble technology

Fig. 19 Equal duration forecast of COVID-19 Cases from the ensemble models using a native plotting method

Fig. 20 Unconstrained forecast of COVID-19 cases in Nigeria Starting from September 14, 2021 to March 30, 2023 using a more advaced plotting method

Fig. 20a

Fig. 20b Constrained forecast of COVID-19 cases in Nigeria Starting from September 14, 2021 to March 30, 2023 using a more advaced plotting method

Fig. 20b Lagged forecasts (1-14 days) of COVID-19 cases in Nigeria

Table 4 Summary of the dynamic COVID-19 forecasts
Model Sep 01, 21 - Mar 03, 23 Sep 08, 21 - Mar 17, 23 Sep 11, 21 - Mar 23, 23 Sep 12, 21 - Mar 25, 23 Sep 13, 21 - Mar 27, 23 Sep 14, 21 - Mar 29, 23
Without knots 146852 320476 399964 413515 433712 439196
Smooth Spline 4149440 3054018 2781952 2544669 2400599 2094742
With knots -1025406 -863720 53801 -373943 -356480 -1040242
Quadratic Polynomial -333492 -283390 -259126 -255514 -249484 -248652
Lower ARIMA -821057 -822030 -764086 -798187 -795611 -848206
Upper ARIMA 1364751 1395234 1454278 1428825 1435210 1397877
Essembled with equal weight 246625 290024 304407 326777 299916 275403
Essembled based on weight 126662 369475 430732 544769 482432 505578
Essembled based on summed weight -23958 -60163 -60515 -80576 -77561 -65417
Essembled based on weight of fit 170950 207234 219757 234242 219948 207023
Table 3 RMSE of the models in the dynamic forecasts
Model Sep 01, 21 - Mar 03, 23 Sep 08, 21 - Mar 17, 23 Sep 11, 21 - Mar 23, 23 Sep 12, 21 - Mar 25, 23 Sep 13, 21 - Mar 27, 23 Sep 14, 21 - Mar 29, 23
Without knots 369.27 368.88 368.51 368.21 367.97 367.65
Smooth Spline 157.48 160.22 160.31 160.72 160.82 161.47
With knots 138.9 139.76 139.47 139.5 139.42 139.53
Quadratic Polynomial 372.33 373.58 374.06 373.91 373.89 373.63
Lower ARIMA 156.56 157.2 156.99 156.95 156.81 156.89
Upper ARIMA 156.56 157.2 156.99 156.95 156.81 156.89
Essembled with equal weight 199.57 200.34 200.23 200.19 200.1 200.13
Essembled based on weight 413.06 412.12 411.03 410.59 410.2 409.9
Essembled based on summed weight 388.65 386.66 385.8 385.44 385.11 384.75
Essembled based on weight of fit 205.78 201.75 199.82 199.58 199.13 199.17

Fig. 21 Percentage of COVID19 cases that resulted into casualty per State as at September 13, 2021

Fig. 22 Percentage of COVID19 cases that recovered per State as at September 13, 2021

Fig. 23 Percentage of recoveries and deaths from COVID19 cases per Zone as at September 13, 2021

Fig. 24 Distribution of COVID19 in the States as at September 13, 2021


  1. Note that Smooth spline does not estimate coefficients and other model-characteristic statistics↩︎

  2. Multiclass Area Under the Curve (MAUC) is the mean of the various AUC estimated from the same data↩︎