Voting Methods & Social Choice: Plurality, Borda, Instant Runoff & Condorcet
Build preference profiles, count plurality and majority, simulate a two-round runoff, score a Borda count with SUMPRODUCT, run instant-runoff elimination rounds in a step table, find the Condorcet winner in a pairwise matrix, count approval ballots and watch the same ballots produce four different winners: 8 graded labs on one fictional town vote. Educational only, no endorsement of any electoral system.
The first lesson is free — no account needed.
About this course
A voting methods and social choice course that counts the same 288 ranked ballots of one fictional town, Elmbrook, in a spreadsheet, for maths students and teachers, political science students and anyone curious about how votes are counted. You summarise the ballots in a preference profile, count first places for the plurality winner and check for a real majority, send the top two options to a runoff, score a Borda count with SUMPRODUCT, run instant-runoff elimination rounds in a step table, build the pairwise matrix and find the Condorcet winner, count approval ballots, and line up six methods side by side to see how many different winners the same ballots produce, with a chart. The course compares methods and their paradoxes and does not recommend or endorse any electoral system. The first lab is free.
Lessons
- Preference Profiles: Ballot Types × CountsFree
- Plurality & the Majority Check Pro
- Two-Round Runoff: Top Two Go to a Second Round Pro
- Borda Count: Points by Rank with SUMPRODUCT Pro
- Instant Runoff (IRV): Elimination Rounds in a Step Table Pro
- Condorcet: the Pairwise Matrix & the Head-to-Head Winner Pro
- Approval Voting: Tick Every Option You Accept Pro
- Same Ballots, Different Winners: Comparing Methods & Paradoxes (with a Chart) Pro