Historical shapefiles

[skvrnami]

Hi,

thanks for your package.
I have a feature request. Some objects such as senatni_obvody, volebni_okrsky and also obce change their boundaries in time. Senate districts due to redistricting, municipalities due to divisions/mergers.
This may cause trouble/inaccuracies when joining a historical data (e.g. electoral results from past elections) and current version of these shapefiles or when doing an analysis of electoral districts over time.
Therefore, it would be great if historical versions of these object were available. (Although I am not sure if ČÚZK or any other entity has such data available).

[jlacko]

Thanks for the idea! It surely has merit.

Keeping history, in addition to fresh data, is in principle possible, and it is true that the administrative areas keep evolving - the recent Act 51/2020 Sb. aligning okres with ORPs and kraje being a nice example of how fluid the situation is.

On the other hand the current internals of the package and S3 bucket on AWS that stores the pre-processed rds files would not quite fit a time dimension.

Introducing it would be somewhat challenging - but not impossible, mind you. What may he a tougher nut to crack is getting hold of historical data. ČUZK does not have unlimited history; a quick check of their VDP site shows earliest data form 2018 - and the senát is even worse / here the data is maintained by staťák and it follows its own special logic (like non - continous regions, and / or not respecting kraje). There is logic in it, but a very special one and not easy to follow.

I will give it a big, hard thought. It may require a major version update. But it feels like a challenge, and I enjoy that ;-)

[skvrnami]

Thanks for the consideration.

Yeah, I know that getting the historical data might be tough. However, the unavailability of data on the website does not mean that there are no such data. From my experience with getting historical election data from CZSO, asking them nicely via email works quite well ;)

[jlacko]

While it may not be practical to follow every minor change of RUIAN with an RCzechia release I feel the need for introducing some high value historical datasets.

Most certainly the 1930 census, which was the last one to give a reliable information about Czech citizens of German nationality / ghosts of whom are well visible even in current election datasets.

Perhaps with some of the commie censuses / regions as required & as time allows.

I am choosing to track the delivery under this still unresolved issue.

[jlacko]

Historický GIS will be our friend here...