Standardise a fitted nowcast

The second extension point of the nowcasting framework (see nowcast_fit()). It receives the object the modelling package returned and must express its predictions in the tidy format tbl.now uses everywhere else.

Usage

# S3 method for class 'diseasenowcasting'
nowcast_tidy(engine, fit, x, ..., quantile_levels)

# S3 method for class 'baselinenowcast'
nowcast_tidy(engine, fit, x, ..., quantile_levels)

# S3 method for class 'epinowcast'
nowcast_tidy(engine, fit, x, ..., quantile_levels)

# S3 method for class 'NobBS'
nowcast_tidy(engine, fit, x, ..., quantile_levels)

# S3 method for class 'surveillance'
nowcast_tidy(engine, fit, x, ..., quantile_levels)

# S3 method for class 'EpiNow2'
nowcast_tidy(engine, fit, x, ..., quantile_levels)

nowcast_tidy(engine, fit, x, ..., quantile_levels)

# Default S3 method
nowcast_tidy(engine, fit, x, ..., quantile_levels)

Arguments

engine

An engine() object; see nowcast_fit().

fit

The object returned by nowcast_fit().

x

The tbl_now the nowcast was produced from.

...

Not forwarded by run_nowcast(), which passes the user's ... to nowcast_fit() only. Anything the tidying step needs – a number of draws, a tuning parameter, a lookup table – must therefore travel inside the object nowcast_fit() returned.

quantile_levels

Numeric vector of probabilities the predictions should be summarised at.

Value

A list with two elements:

predictions

A data frame with one row per (event date, stratum, quantile level) and the columns <event_date>, the strata columns, .quantile_level and .value.

draws

Either NULL, or a data frame with one row per (event date, stratum, draw) and the columns <event_date>, the strata columns, .draw and .value.

When draws is supplied and predictions is NULL, run_nowcast() derives the quantiles from the draws for you.

See also

nowcast_fit(), run_nowcast()

Examples

# See `?nowcast_fit` for a complete two-method backend.
methods(nowcast_tidy)
#> [1] nowcast_tidy.EpiNow2*           nowcast_tidy.NobBS*            
#> [3] nowcast_tidy.baselinenowcast*   nowcast_tidy.default*          
#> [5] nowcast_tidy.diseasenowcasting* nowcast_tidy.epinowcast*       
#> [7] nowcast_tidy.example*           nowcast_tidy.surveillance*     
#> see '?methods' for accessing help and source code