conversionRead: Read population conversion table

In bcgov/dbutils: Utility functions to process and modify BC Stats' population databases

Read population conversion table

Description

Read a conversion table so it can be examined. Conversion tables represent the proportional relationship ("split") between source and destination geographies, and are named as FROM_TO_YEAR. For example, the table that converts from LHA to SD based on 2019 matches is called LHA_SD_2019. (Historical APL naming was similar, but used dashes in place of underscores, and included the word TABLE before the year (e.g., LHA-SD-TABLE2019).)

Conversion tables are in the "I:/ConversionTables/" folder, to ensure consistency across population systems, and because dbConvert uses that hardcoded path to find the required conversion table. Conversion tables are expected to be .xlsx files with three unnamed columns with the proportional relationship (aka, "split"), source and destination geographies.

Usage

conversionRead(conv_path)

Arguments

conv_path

The full path to the conversion table Excel file.

Details

Data is available at varying levels of detail, mostly dependent on some form of geography. For example, Census-related data may be accessible for every Dissemination Block, while health-related data may only be available at the Local Health Area (LHA) level. As such, there exists a need to transfer, or convert, information from one geography to another. This is achieved using a conversion table that converts data from Geography A (source) to B (destination).

A conversion table is based on population counts at a very high level of detail. BC Stats uses Dissemination Block-level population totals from the most recent Census. Additionally, one would need geographic software (like ArcMap or QGIS) to establish the allocation of Dissemination Blocks to the conversion geographies. While the following mentions the underlying linkage between geographies being established via Dissemination Blocks, one could technically use any (small) geography to establish this relationship.

Essentially, the (total) population at the Dissemination Block-level is required to provide the fundamental relationship between the allocation of Geography A (source) and the allocation to Geography B (destination).

Value

A data.frame object with three variables: split, source, and destination.

See Also

Overall package documentation: dbutils()

Other conversion helpers: conversionTables(), dbConvert(), geogConvert()

Examples

## Not run:   conversionRead(conv_path = "I:/ConversionTables/Table-LHA-HSDA-2019.xlsx")  
## Not run:   conversionRead(conv_path = "I:/ConversionTables/Table-LHA-SD-2019.xlsx")  

bcgov/dbutils documentation built on Sept. 30, 2022, 12:04 a.m.