# Validating Your Typology

The `daily_internet_users` data set is created by this code, which is not evaluated here in this vignette:

    isoc_r_iuse_i <- eurostat::get_eurostat("isoc_r_iuse_i",
                                            time_format = "num")

    daily_internet_users <- isoc_r_iuse_i  %>%
      dplyr::filter ( unit == "PC_IND",          # percentage of individuals
                      indic_is == "I_IDAY") %>%  # daily internet users
      select ( all_of(c("geo", "time", "values") )

Simply downloading a regional statistics from the Eurostat data warehouse and placing the observation on the same map does not work. If you look into the data, you may realize that the geo codes of French, Lithuanian or Hungarian regions, to name a few, do not match in the years 2012 and 2018.

Let’s have a look at these countries in two years, using the helper function `get_country_code`. The year 2012 is coded with the `NUTS2010` typology and the year 2018 with the `NUTS2016` typology. Then we use the `valideate_nuts_region` function with the default `NUTS2016` (which is currently valid in the European Union) and the obsolete `NUTS2010` definitions.

    test <- daily_internet_users  %>%
      mutate ( country_code = get_country_code(geo = .data$geo) ) %>%
      dplyr::filter ( time %in% c(2012, 2018),
                      country_code %in% c("FR", "HU", "LT")) %>%
      mutate ( time = paste0("Y", time )) %>%
      pivot_wider ( names_from ="time", values_from = "values") %>%
      validate_nuts_regions() %>%  # default year the current valid 2016
      validate_nuts_regions( nuts_year = 2010 )

The following NUTS regions codes are not valid in the 2010 definition. These sub-national divisions were defined in 2013 or 2016. Some of these regional boundaries did not change, but got new codes after altering the administrative divisions of France. Some of the seemingly missing 2012 data can be found under different codes.

    # only first 10 regions are printed
    knitr::kable(
      head(test [ ! test$valid_2010, ], 10)
    )

geo | country_code | Y2018 | Y2012 | orig_typology | valid_2016 | typology | valid_2010
--- | --- | --- | --- | --- | --- | --- | ---
FRB | FR | 70 | NA | nuts_level_1 | TRUE | NA | FALSE
FRB0 | FR | 70 | NA | nuts_level_2 | TRUE | NA | FALSE
FRC | FR | 72 | NA | nuts_level_1 | TRUE | NA | FALSE
FRC1 | FR | 71 | NA | nuts_level_2 | TRUE | NA | FALSE
FRC2 | FR | 74 | NA | nuts_level_2 | TRUE | NA | FALSE
FRD | FR | 79 | NA | nuts_level_1 | TRUE | NA | FALSE
FRD1 | FR | 78 | NA | nuts_level_2 | TRUE | NA | FALSE
FRD2 | FR | 80 | NA | nuts_level_2 | TRUE | NA | FALSE
FRE | FR | 75 | NA | nuts_level_1 | TRUE | NA | FALSE
FRE1 | FR | 73 | NA | nuts_level_2 | TRUE | NA | FALSE

And there are two regions that are not valid in 2016, because these typologies were changed. Vilnius and Budapest, two big cities, were detached from their larger containing regional units.

    knitr::kable(
      test [ ! test$valid_2016, ]
    )

geo | country_code | Y2018 | Y2012 | orig_typology | valid_2016 | typology | valid_2010
--- | --- | --- | --- | --- | --- | --- | ---
HU10 | HU | NA | 68 | NA | FALSE | nuts_level_2 | TRUE
LT00 | LT | NA | 49 | NA | FALSE | nuts_level_2 | TRUE

Especially in the case of Budapest and Central Hungary, the comparative data can be produced for different boundary definitions, because the boundary change was simple. (Budapest was removed from Central Hungary.) In Lithuania, the change was not more complex, but unfortunately it cut through a far less rarely used typology level, `NUTS3`. While the change is simple, the replacement data is usually not published.

# Citations and related work

### Citing the data sources

Eurostat data: cite Eurostat.

Administrative boundaries: cite EuroGeographics.

### Citing the regions R package

For main developer and contributors, see the package homepage.

This work can be freely used, modified and distributed under the GPL-3 license:

    citation("regions")
    #>
    #> To cite package 'regions' in publications use:
    #>
    #>   Daniel Antal (2021). regions: Processing Regional Statistics. R
    #>   package version 0.1.8. https://regions.dataobservatory.eu/
    #>
    #> A BibTeX entry for LaTeX users is
    #>
    #>   @Manual{,
    #>     title = {regions: Processing Regional Statistics},
    #>     author = {Daniel Antal},
    #>     year = {2021},
    #>     note = {R package version 0.1.8},
    #>     url = {https://regions.dataobservatory.eu/},
    #>   }

### Contact

For contact information, see the package homepage.