I found a great tool which allows one to see the impact of the STV voting system.
First thing I did was to simplify how many parties there are, mostly because it made it a lot easier to see the final outcome and it was less clicking.
You need to have Java installed for this application. The app is not flashy but it does all it needs to do.
First thing you choose how many MLA’s and parties are in the election. For me I used four parties and five MLA’s.
The second step takes a bit more thought/work. This is where you enter different ballot combinations. Since there are a lot of different possible combinations, I just tried to use as many different ones as possible. You also have the option of how many ballots were entered for each selection – I used random numbers here to get a more realistic view.
The final step is the vote count – this is cool and gives a break down for each count, you may need to make the Java applet a bit bigger to see all the details. You keep “counting” until all candidates are elected or eliminated.
When you select voter details it shows you the breakdown of how each vote is being used and at what percentage their vote is being used.
Overall this is a very neat tool and may help you see how the break down is different using STV. I personally found it a bit confusing to start with, but after reading the FAQ’s and changing up the number of parties/MLA’s really helped simplify it for me. Putting in as many different combinations as possible increases the clarity in the vote counting. Let me know how you find it!