This app lets you try the effect of different electoral (voting) systems.
Their task is to calculate the number of seats (typically) in the parliament
from number of votes for each political party. Systems may give proportional
results, or prefer larger or smaller parties.
This app was used as a tool to analyze Czech parliamentry elections 2013,
see the article
(in Czech language), and again in 2017 with the analysis of potential pre-election coalitions,
see the article
(in Czech language).
Electoral systems can be very specific in each country, so only some most common
parameters can be set in the application.
These are mathematical formulas that convert votes into seats in each electoral district.
Both largest remainder methods
and highest averages methods
Division into Electoral Districts
Having the country divided into more
districts helps larger parties.
With increasing number of electoral districts, the number of seats available in each
of them is decreasing, and it is more difficult for smaller parties to win any of them.
You can define the electoral districts inside the app, and set election results
in each of them, or set the result only on the country level, that is automatically
copied into all districts.
The app contains the example of different set of electoral districts in the Czech Republic,
with division into 8 districts (till 1998), 14 districts (from 2002) and hypothetical
divisions into 35 and 1 district.
Formal Election Thresholds
represent the minimum vote share a party requires to secure representation.
It can be set nationwide, on a per-district basis, or be set to zero at all.
For example, Spain uses the system with 3% threshold in each district.
Sweden has 4% nationwide threshold, but if the party reaches 12% in one
district, it will be represented even if it does not reach the 4% level nationally.
It is also possible to set the special thresholds for alliances according
to the number of their members.
Total Number of Seats, Bonus for Winner
And of course, you can set the total number of seats that is to be allocated
with the system. It is also possible to set a
Pre-election simulator lets you try, what if some parties formed a coalition
instead of competing alone. Does the electoral system assigns more mandates?
How much more?
Calculation is done by summing the votes of cooperating parties.
Of course, you can compare the results of selected systems with each other.
The app lets you add situations into the comparison table, and automatically shows the
different input parameters with the results for each party that received representation.
The app calculates several proportionality indices, that measure the systems according to their proportionality.
Their scores can be displayed in the comparison table too.
Indices implemented (see descriptions inside the app):
- Largest Deviation
- Least Squares
- RR, ARR, ERR, SRR
The app comes filled with datasets for the following parliamentary elections:
- Czechia: 1998, 2002, 2006, 2010, 2013, 2017
- Netherlands: 2006, 2010, 2012
- Slovakia: 2010, 2012
Developer: Jan Adamec
The app is prepared to be translated to any language. Please contact me if you
would like to translate it to yours. Thanks to all volunteers!
- Currently: English, Czech
I am open to cooperation with any educational or political institution to
implement more features they would need. Please contact me.
The app does not collect any personal information nor data about app usage.
This app has 17 years of history (since 2000), when there was a discussion in my country
about the changing the electoral system to be much less proportional. I wanted
to try the effects of the changes so I made the Windows application, which enabled
it. The current iPad app builds upon the functions developed there.
You can download the Windows version of this app here, but it does contain several
minor bugs and mistakes, and setting up a new country is very difficult. And is in Czech only!
Download: volby120.zip (357 KB)