Generate point nowcast

This function ingests a reporting triangle matrix and optionally, a delay distribution, and returns a completed reporting square which represents the point nowcast. If a delay distribution is specified, this will be used to generate the nowcast, otherwise, a delay distribution will be estimated from the reporting_triangle.

Usage

generate_pt_nowcast_mat(
  reporting_triangle,
  max_delay = ncol(reporting_triangle) - 1,
  n = nrow(reporting_triangle),
  delay_pmf = NULL
)

Arguments

reporting_triangle

Matrix of the reporting triangle, with rows representing the time points of reference and columns representing the delays. Can be a reporting matrix or incomplete reporting matrix.

max_delay

Integer indicating the maximum delay to estimate, in units of the delay. The default is to use the whole reporting triangle, ncol(triangle) -1.

n

Integer indicating the number of reference times (observations) to be used in the estimate of the reporting delay, always starting from the most recent reporting delay. The default is to use the whole reporting triangle, so nrow(triangle).

delay_pmf

Vector of delays assumed to be indexed starting at the first delay column in triangle_to_nowcast.

Value

point_nowcast_matrix Matrix of the same number of rows and columns as the reporting_triangle but with the missing values filled in as point estimates.

Examples

triangle <- matrix(
  c(
    80, 50, 25, 10,
    100, 50, 30, 20,
    90, 45, 25, NA,
    80, 40, NA, NA,
    70, NA, NA, NA
  ),
  nrow = 5,
  byrow = TRUE
)
point_nowcast_matrix <- generate_pt_nowcast_mat(
  reporting_triangle = triangle
)
print(point_nowcast_matrix)
#>      [,1]     [,2]     [,3]     [,4]
#> [1,]   80 50.00000 25.00000 10.00000
#> [2,]  100 50.00000 30.00000 20.00000
#> [3,]   90 45.00000 25.00000 14.33572
#> [4,]   80 40.00000 23.17697 12.82918
#> [5,]   70 37.26249 20.72155 11.46862