1. **Problem Statement:**
Given a voting profile with 70 voters and their ranked preferences for candidates A, B, C, and D, determine the winners when two candidates are elected using three methods: Survivor System Runoff, Borda Count, and Single Transferable Vote (STV).
2. **Data Setup:**
Voter groups and their preferences:
- 9 voters: A > B > C > D
- 11 voters: A > C > B > D
- 12 voters: B > A > D > C
- 10 voters: B > D > A > C
- 17 voters: D > C > A > B
- 11 voters: C > D > B > A
Total voters = 9 + 11 + 12 + 10 + 17 + 11 = 70
---
### Survivor System Runoff
3. **Step 1: Count first-choice votes:**
- A: 9 + 11 = 20
- B: 12 + 10 = 22
- C: 11
- D: 17
4. **Step 2: Eliminate candidate with fewest first-choice votes:**
Candidate C has 11 votes, the fewest, so eliminate C.
5. **Step 3: Redistribute C's votes to next preferred candidate:**
C's 11 voters ranked C > D > B > A, so their votes go to D.
6. **Step 4: New first-choice totals:**
- A: 20
- B: 22
- D: 17 + 11 = 28
7. **Step 5: Eliminate candidate with fewest votes:**
A has 20, B has 22, A is lowest, eliminate A.
8. **Step 6: Redistribute A's votes:**
A's 20 voters ranked A > B > C > D or A > C > B > D.
Since C is eliminated, next preference after A is B for both groups.
So, 20 votes go to B.
9. **Step 7: Final tally:**
- B: 22 + 20 = 42
- D: 28
10. **Step 8: Winners:**
Top two candidates are B (42 votes) and D (28 votes).
---
### Borda Count Method
11. **Step 1: Assign points:**
For 4 candidates, points per rank: 1st = 3, 2nd = 2, 3rd = 1, 4th = 0.
12. **Step 2: Calculate points per candidate:**
Calculate points for each candidate by summing over all voter groups:
| Candidate | Calculation | Total Points |
|-----------|-----------------------------------------------------------------------------|--------------|
| A | (9*3)+(11*3)+(12*2)+(10*2)+(17*1)+(11*0) = 27+33+24+20+17+0 = 121 |
| B | (9*2)+(11*1)+(12*3)+(10*3)+(17*0)+(11*2) = 18+11+36+30+0+22 = 117 |
| C | (9*1)+(11*2)+(12*0)+(10*0)+(17*2)+(11*3) = 9+22+0+0+34+33 = 98 |
| D | (9*0)+(11*0)+(12*1)+(10*1)+(17*3)+(11*1) = 0+0+12+10+51+11 = 84 |
13. **Step 3: Winners:**
Top two candidates by points are A (121) and B (117).
---
### Single Transferable Vote (STV) Method
14. **Step 1: Calculate quota:**
Quota = $\left\lfloor \frac{70}{2+1} \right\rfloor + 1 = \left\lfloor 23.33 \right\rfloor + 1 = 24$ votes needed to win.
15. **Step 2: Count first-choice votes:**
- A: 20
- B: 22
- C: 11
- D: 17
No candidate reaches quota.
16. **Step 3: Eliminate candidate with fewest votes:**
C with 11 votes is eliminated.
17. **Step 4: Redistribute C's votes:**
C's 11 votes go to D (next preference).
18. **Step 5: New totals:**
- A: 20
- B: 22
- D: 28
19. **Step 6: D reaches quota (28 >= 24), D is elected. Transfer surplus votes (28 - 24 = 4) proportionally.
20. **Step 7: Transfer surplus votes:**
D's surplus votes are transferred to next preferences of D voters:
- From 17 original D voters: next preference is C (eliminated), then A.
- From 11 transferred C voters: next preference after C is D (already elected), then B.
Assuming proportional transfer, surplus votes mostly go to A and B.
21. **Step 8: After transfer, A and B totals increase; the candidate with highest votes among A and B wins second seat.
22. **Step 9: Conclusion:**
Likely winners are D and B or D and A depending on transfer details.
---
**Final answers:**
- Survivor System Runoff winners: B and D
- Borda Count winners: A and B
- STV winners: D and B (most likely)
Voting Methods 0E140E
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