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Read parameter PMF into memory

read_interval_pmf.Rd

Using DuckDB from a parquet file. The function expects the file to be in SCD2 format with column names:

  • parameter

  • geo_value

  • disease

  • start_date

  • end_date

  • value

Usage

read_interval_pmf(
  path,
  disease = c("COVID-19", "Influenza", "test"),
  as_of_date,
  parameter = c("generation_interval", "delay", "right_truncation"),
  group = NA,
  report_date = NA
)

Arguments

path

A path to a local file

disease

One of COVID-19 or Influenza

as_of_date

Use the parameters that were used in production on this date. Set for the current date for the most up-to-to date version of the parameters and set to an earlier date to use parameters from an earlier time period.

parameter

One of "generation interval", "delay", or "right-truncation

group

An optional parameter to subset the query to a parameter with a particular two-letter state abbrevation. Right now, the only parameter with state-specific estimates is right_truncation.

report_date

An optional parameter to subset the query to a parameter on or before a particular report_date. Right now, the only parameter with report date-specific estimates is right_truncation. Note that this is similar to, but different from as_of_date. The report_date is used to select the particular value of a time-varying estimate. This estimate may itself be regenerated over time (e.g., as new data becomes available or with a methodological update). We can pull the estimate for date report_date as generated on date as_of_date.

Value

A PMF vector

Details

start_date and end_date specify the date range for which the value was used. end_date may be NULL (e.g. for the current value used in production). value must contain a pmf vector whose values are all positive and sum to 1. all other fields must be consistent with the specifications of the function arguments describe below, which are used to query from the .parquet file.

SCD2 format is shorthand for slowly changing dimension type 2. This format is normalized to track change over time: https://en.wikipedia.org/wiki/Slowly_changing_dimension#Type_2:_add_new_row