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A generic wrapper around enw_posterior() with opinionated defaults to extract the posterior prediction for the nowcast ("pp_inf_obs" from the stan code). The functionality of this function can be used directly on the output of epinowcast() using the supplied summary.epinowcast() method.

Usage

enw_nowcast_summary(
  fit,
  obs,
  max_delay = NULL,
  timestep = "day",
  probs = c(0.05, 0.2, 0.35, 0.5, 0.65, 0.8, 0.95)
)

Arguments

fit

A cmdstanr fit object.

obs

An observation data.frame containing reference_date columns of the same length as the number of rows in the posterior and the most up to date observation for each date. This is used to align the posterior with the observations. The easiest source of this data is the output of latest output of enw_preprocess_data() or enw_latest_data().

max_delay

Maximum delay to which nowcasts should be summarised. Must be equal (default) or larger than the modelled maximum delay. If it is larger, then nowcasts for unmodelled dates are added by assuming that case counts beyond the modelled maximum delay are fully observed.

timestep

The timestep to used. This can be a string ("day", "week", "month") or a numeric whole number representing the number of days.

probs

A vector of numeric probabilities to produce quantile summaries for. By default these are the 5%, 20%, 80%, and 95% quantiles which are also the minimum set required for plotting functions to work.

Value

A data.frame summarising the model posterior nowcast prediction. This uses observed data where available and the posterior prediction where not.

Examples

fit <- enw_example("nowcast")
enw_nowcast_summary(
  fit$fit[[1]],
  fit$latest[[1]],
  fit$max_delay
  )
#>     reference_date report_date .group max_confirm location age_group confirm
#>             <IDat>      <IDat>  <num>       <int>   <fctr>    <fctr>   <int>
#>  1:     2021-08-03  2021-08-22      1         149       DE       00+     149
#>  2:     2021-08-04  2021-08-22      1         166       DE       00+     166
#>  3:     2021-08-05  2021-08-22      1         133       DE       00+     133
#>  4:     2021-08-06  2021-08-22      1         137       DE       00+     137
#>  5:     2021-08-07  2021-08-22      1         139       DE       00+     139
#>  6:     2021-08-08  2021-08-22      1          97       DE       00+      97
#>  7:     2021-08-09  2021-08-22      1          58       DE       00+      58
#>  8:     2021-08-10  2021-08-22      1         175       DE       00+     175
#>  9:     2021-08-11  2021-08-22      1         233       DE       00+     233
#> 10:     2021-08-12  2021-08-22      1         237       DE       00+     237
#> 11:     2021-08-13  2021-08-22      1         204       DE       00+     204
#> 12:     2021-08-14  2021-08-22      1         189       DE       00+     189
#> 13:     2021-08-15  2021-08-22      1         125       DE       00+     125
#> 14:     2021-08-16  2021-08-22      1          98       DE       00+      98
#> 15:     2021-08-17  2021-08-22      1         242       DE       00+     242
#> 16:     2021-08-18  2021-08-22      1         223       DE       00+     223
#> 17:     2021-08-19  2021-08-22      1         202       DE       00+     202
#> 18:     2021-08-20  2021-08-22      1         171       DE       00+     171
#> 19:     2021-08-21  2021-08-22      1         112       DE       00+     112
#> 20:     2021-08-22  2021-08-22      1          45       DE       00+      45
#>     reference_date report_date .group max_confirm location age_group confirm
#>     cum_prop_reported delay prop_reported    mean median         sd     mad
#>                 <num> <num>         <num>   <num>  <num>      <num>   <num>
#>  1:                 1    19   0.000000000 149.000    149   0.000000  0.0000
#>  2:                 1    18   0.000000000 167.426    167   1.318432  1.4826
#>  3:                 1    17   0.000000000 135.789    136   1.854162  1.4826
#>  4:                 1    16   0.000000000 141.288    141   2.378805  1.4826
#>  5:                 1    15   0.007194245 146.019    146   3.079630  2.9652
#>  6:                 1    14   0.000000000 103.853    104   2.969884  2.9652
#>  7:                 1    13   0.000000000  62.766     63   2.432110  2.9652
#>  8:                 1    12   0.000000000 185.035    185   3.847932  4.4478
#>  9:                 1    11   0.000000000 256.031    256   6.498790  5.9304
#> 10:                 1    10   0.004219409 267.692    267   7.713536  7.4130
#> 11:                 1     9   0.000000000 236.057    235   8.508004  7.4130
#> 12:                 1     8   0.015873016 231.407    231  10.083304 10.3782
#> 13:                 1     7   0.040000000 164.876    164   9.848127 10.3782
#> 14:                 1     6   0.010204082 128.858    128   8.134495  7.4130
#> 15:                 1     5   0.012396694 293.309    292  11.938427 11.8608
#> 16:                 1     4   0.017937220 293.042    292  15.799489 14.8260
#> 17:                 1     3   0.019801980 291.478    290  21.108128 19.2738
#> 18:                 1     2   0.070175439 293.178    291  29.440398 28.1694
#> 19:                 1     1   0.383928571 308.518    302  51.151522 46.7019
#> 20:                 1     0   1.000000000 375.644    363 103.424281 91.1799
#>     cum_prop_reported delay prop_reported    mean median         sd     mad
#>         q5   q20    q35   q50    q65   q80    q95      rhat  ess_bulk  ess_tail
#>      <num> <num>  <num> <num>  <num> <num>  <num>     <num>     <num>     <num>
#>  1: 149.00   149 149.00   149 149.00   149 149.00        NA        NA        NA
#>  2: 166.00   166 167.00   167 168.00   168 170.00 0.9997778 1003.5643  828.2026
#>  3: 133.00   134 135.00   136 136.00   137 139.00 1.0005878  991.0805  916.0962
#>  4: 138.00   139 140.00   141 142.00   143 146.00 1.0056729 1041.2029  872.9772
#>  5: 141.00   143 145.00   146 147.00   148 152.00 1.0001025  991.1639  885.1056
#>  6: 100.00   101 102.65   104 105.00   106 109.00 0.9991163  982.3833  917.3468
#>  7:  59.00    61  62.00    63  63.00    65  67.00 1.0009067  911.2098  793.6687
#>  8: 179.00   182 183.00   185 186.00   188 192.00 1.0002531 1004.7790  972.0392
#>  9: 246.00   251 253.00   256 258.00   261 268.00 0.9997137 1025.3311  936.5679
#> 10: 256.00   261 265.00   267 270.00   274 282.00 1.0004951 1040.1417 1008.8448
#> 11: 223.00   229 233.00   235 239.00   243 251.00 0.9985724 1201.4893  863.9704
#> 12: 216.00   222 227.00   231 234.00   240 250.00 1.0035756  751.4194  655.0188
#> 13: 150.00   157 160.00   164 168.00   173 181.00 1.0025186  927.9122  920.9413
#> 14: 117.00   122 125.00   128 131.00   135 143.00 1.0010009 1080.4014  964.2083
#> 15: 276.00   283 288.00   292 297.00   303 315.00 1.0002316 1159.2978  984.6276
#> 16: 268.00   280 286.00   292 299.00   306 320.00 1.0047058 1087.6045  957.9921
#> 17: 260.00   274 282.00   290 298.35   308 330.00 1.0002334 1129.6391  914.6275
#> 18: 250.00   269 280.00   291 301.00   316 344.00 0.9993186 1126.3831  903.3288
#> 19: 239.00   267 286.00   302 322.00   343 399.10 0.9992178 1328.2832  998.7573
#> 20: 233.95   292 327.00   363 397.00   447 565.05 0.9991666 1554.0485  999.3402
#>         q5   q20    q35   q50    q65   q80    q95      rhat  ess_bulk  ess_tail