Comprehensive Guide to Elections, Electoral Integrity, and Electoral Systems

Elections, Democratic Governance, and Global Trends

  • Core Concepts and Definitions:

    • An electoral system is defined as a set of laws that regulate electoral competition between candidates, parties, or both.

    • Democracies are frequently classified and analyzed according to the specific properties and mechanics of their electoral systems.

    • An electoral formula determines the precise mathematical algorithm or rule through which cast votes are translated into legislative or executive seats.

  • Global Proliferation of Direct Elections:

    • Elections are increasingly utilized to fill legislative and executive offices worldwide.

    • Almost all contemporary independent sovereign states utilize direct popular elections to elect members to the lower house of their national parliaments.

    • Over the post-World War II era, the decennial frequency of both legislative and presidential elections has grown substantially, accelerating sharply through the 1990s, 2000s, and 2010s.

Legislative and presidential elections conducted worldwide by decade from the 1950s through the 2010s

Electoral Integrity, Malpractice, and Election Forensics

  • Normative Standards of Electoral Integrity:

    • Electoral integrity refers to the extent to which the conduct of an election meets international standards and global norms concerning "good" elections.

    • These standards and norms are formally codified in international treaties, conventions, covenants, and guidelines issued by multilateral bodies and regional organizations.

    • Violations of international standards across any stage of the electoral cycle are designated as electoral malpractice.

  • Cross-National Variation and Structural Determinants:

    • While democratic regimes generally demonstrate significantly higher levels of electoral integrity than dictatorships, substantial variation exists within both democratic and non-democratic categories.

    • Electoral integrity is shaped by four primary domestic and systemic factors:

      • Domestic structural constraints: Socioeconomic conditions, level of economic development, and historical state capacity.

      • The role of the international community: Diplomatic pressure, foreign aid conditionality, and treaty oversight.

      • Institutional design: The constitutional framework, separation of powers, and statutory rules governing contestation.

      • Electoral management bodies (EMBs): The degree of formal independence, administrative competence, and financial autonomy of election commissions.

    • Evaluative indices such as the Perception of Electoral Integrity (PEI) index assess integrity across multiple distinct sub-dimensions: electoral laws, administrative procedures, district boundaries, voter registration, party and candidate registration, media coverage, campaign finance, voting processes, the vote count, post-election results handling, and the autonomy of electoral authorities.

  • Strategies for Identifying Electoral Fraud:

    • Two primary empirical methodologies are utilized to uncover malpractice:

      • Election monitoring: On-site qualitative and quantitative observation conducted by domestic civil society observer groups or international missions.

      • Election forensics: Statistical and mathematical analysis of official voting returns to detect irregularities, anomalous distributions, or manufactured vote counts.

  • Benford's Law in Election Forensics:

    • Mathematical Basis: Benford's Law posits that across naturally occurring multi-digit numerical data, the distribution of leading digits is non-uniform. Lower digits appear as the first or second digit far more frequently than higher digits.

    • Forensic Application: Human agents fabricating data tend to assign digits uniformly or exhibit specific cognitive biases, violating the logarithmic distributions predicted by Benford's Law (Cho and Gaines 2007).

    • Digit Probabilities and Expectations:

      • The theoretical probability distribution of first and second digits under Benford's Law is formalized as follows:

Digit

First Digit Probability

Second Digit Probability

00

N/A

0.1200.120

11

0.3010.301

0.1140.114

22

0.1760.176

0.1090.109

33

0.1250.125

0.1040.104

44

0.0970.097

0.1000.100

55

0.0790.079

0.0970.097

66

0.0670.067

0.0930.093

77

0.0580.058

0.0900.090

88

0.0510.051

0.0880.088

99

0.0460.046

0.0850.085

Expected Mean

3.4413.441

4.1874.187

  • In forensic electoral studies, scholars generally evaluate the distribution of the second digit rather than the first digit, as second-digit tests are less vulnerable to district magnitude and baseline population scale constraints (Mebane 2006, 2008; Pericchi and Torres 2011; Cantu and Saiegh 2011).

  • For instance, forensic analysis applied to official vote tallies from 45,69245{,}692 ballot boxes in the 2009 presidential election in Iran identified statistically significant deviations from Benford's Law, providing empirical evidence of systemic manipulation (Mebane 2013).

Taxonomy of Electoral System Families

  • Primary System Classifications:

    • Electoral systems are grouped into three overarching families according to their electoral formula:

      • Majoritarian systems

      • Proportional systems

      • Mixed systems

  • Majoritarian Family Variants:

    • Plurality Rules:

      • Single-Member District Plurality (SMDP)

      • Single Nontransferable Vote (SNTV)

      • Block Vote (BV)

      • Party Block Vote (PBV)

      • Limited Vote (LV)

      • Borda Count (BC) and Modified Borda Count

    • Absolute Majority Rules:

      • Alternative Vote (AV)

      • Two-Round System: Majority-Runoff (TRS)

      • Two-Round System: Majority-Plurality (TRS)

  • Proportional Family Variants:

    • Quota-Based Systems: Hare, Hagenbach-Bischoff, Droop, Imperiali, and Reinforced Imperiali quotas, paired with remainder allocation rules.

    • Divisor (Highest Average) Systems: d'Hondt, Sainte-Laguë, and Modified Sainte-Laguë divisors.

    • Ballot Architecture: List Proportional Representation (List PR) versus Single Transferable Vote (STV).

  • Mixed Family Variants:

    • Independent Mixed Systems: Coexistence and Superposition.

    • Dependent Mixed Systems: Fusion, Correction (Compensatory), and Conditional.

Majoritarian Electoral Systems: Plurality and Absolute Majority

  • Core Logic of Majoritarianism:

    • A majoritarian electoral system awards legislative or executive seats to the candidates or political parties that secure either a plurality or an absolute majority of cast votes.

  • Single-Member District Plurality (SMDP):

    • Mechanism: Voters cast a single ballot for a individual candidate within a single-member electoral district. The candidate receiving the highest number of votes wins the seat, regardless of whether they achieve an absolute majority.

    • Theoretical Bounds: A candidate can mathematically win an SMDP district with an extremely low percentage or count (hypothetically, two votes if all other candidates receive one vote each).

    • Case Study (Bedford Constituency, UK Legislative Elections, 2019):

Candidate

Party

Votes

Vote Share (%)

Mohammad Yasin

Labour

20,49120{,}491

43.343.3

Ryan Henson

Conservative

20,34620{,}346

43.043.0

Henry Vann

Liberal Democrat

4,6084{,}608

9.79.7

Adrian Spurrell

Green

960960

2.02.0

Charles Bunker

Brexit

896896

1.91.9

-   In this election, Mohammad Yasin won the seat with a plurality of 43.3%43.3\% of the total vote, defeating Ryan Henson by a margin of 145145 votes, despite 56.7%56.7\% of the electorate voting for other candidates.
-   **Institutional Strengths:**
    -   *Simplicity:* Understandable rules for electors and straightforward, inexpensive ballot tabulation.
    -   *Identifiable accountability:* With exactly one representative per geographic constituency, voters can directly locate political responsibility for district outcomes.
-   **Institutional Weaknesses:**
    -   High levels of unrepresented or "wasted" votes.
    -   Significant disproportionality between national vote share and total seats won.
  • Single Nontransferable Vote (SNTV):

    • Mechanism: Voters cast a single, non-transferable, candidate-centered vote in a multimember electoral district. Candidates receiving the highest overall vote totals are elected until all district seats are filled.

    • Introduces intra-party competition, as multiple candidates from the same party contend against each other for district seats.

  • The Alternative Vote (AV):

    • Mechanism: A preferential, candidate-centered system deployed in single-member districts. Voters rank candidates ordinally (1,2,3,…1, 2, 3, \dots).

    • If a candidate secures an absolute majority (>50%> 50\%) of first-preference votes, they are elected immediately.

    • If no candidate obtains an absolute majority, the candidate with the lowest number of first-preference votes is eliminated. Their ballots are redistributed among the remaining candidates according to designated second preferences.

    • This elimination and reallocation cycle recurs iteratively until a candidate achieves an absolute majority of total votes cast (in full preferential voting) or of valid ballots remaining (in optional preferential voting).

    • Case Study (Richmond Constituency, New South Wales, Australian Federal Election, 1990):

Candidate

Count 1 (No.)

Count 1 (%)

Count 2

Count 3

Count 4

Count 5

Count 6

Count 7 (Final No.)

Count 7 (Final %)

Stan Gibbs

4,3464{,}346

6.36.3

4,3804{,}380

4,4204{,}420

4,5044{,}504

4,6834{,}683

Elim.

—

—

Neville Newell

18,42318{,}423

26.726.7

18,46718{,}467

18,48418{,}484

18,54418{,}544

18,68318{,}683

20,23820{,}238

34,66434{,}664

50.550.5

Gavin Baillie

187187

0.30.3

Elim.

—

—

—

—

—

—

Alan Sims

1,0321{,}032

1.51.5

1,0531{,}053

1,0591{,}059

1,1161{,}116

Elim.

—

—

—

Ian Paterson

445445

0.60.6

480480

530530

Elim.

—

—

—

—

Dudley Leggett

279279

0.40.4

294294

Elim.

—

—

—

—

—

Charles Blunt

28,25728{,}257

40.940.9

28,27428{,}274

28,30328{,}303

28,41628{,}416

28,97828{,}978

29,77829{,}778

33,98033{,}980

49.549.5

Helen Caldicott

16,07216{,}072

23.323.3

16,09116{,}091

16,23716{,}237

16,43816{,}438

16,65816{,}658

18,90318{,}903

Elim.

—

  • Charles Blunt (National Party leader) initially led on the first count with 40.9%40.9\% against Neville Newell (Labor) at 26.7%26.7\%.

  • Through subsequent preference redistributions following the elimination of minor candidates and third-place independent candidate Helen Caldicott, Newell amassed sufficient transferred preferences to reach 34,66434{,}664 votes (50.5%50.5\%), overcoming Blunt's 33,98033{,}980 votes (49.5%49.5\%).

  • Political parties utilize standardized instructional leaflets ("How-to-Vote cards") distributed at polling sites to coordinate voter rankings and direct preference flows toward preferred coalition partners.

Australian Green Party How-to-Vote card illustrating complete candidate ranking for the Canning constituency
  • Majority-Runoff Two-Round Systems (TRS):

    • Mechanism: Electors cast a single candidate vote in a single-member district. If any candidate achieves an absolute majority (>50%> 50\%) in the first round, they are elected immediately. If no candidate reaches this threshold, the two highest vote-earners advance to a decisive second-round runoff.

    • Single-Round Decisive Outcome (Burundi Presidential Election, 2020):

Candidate

Party

First Round Vote Share (%)

Évariste Ndayishimiye

CNDD-FDD

71.4571.45

Agathon Rwasa

National Congress for Liberty

25.1525.15

Gaston Sindimwo

Union for National Progress

1.701.70

Domitien Ndayizeye

Kira Burundi Coalition

0.570.57

Léonce Ngendakumana

Front for Democracy in Burundi

0.490.49

Dieudonné Hahimana

Independent

0.430.43

Francis Rohero

Independent

0.210.21

  • Because Évariste Ndayishimiye obtained an absolute majority (71.45%71.45\%), no runoff election was triggered.

  • Two-Round Runoff Reversal (Uruguay Presidential Election, 2019):

Candidate

Party

Round 1 Vote Share (%)

Round 2 Vote Share (%)

Daniel Martinez

Broad Front

40.4940.49

49.2149.21

Luis Alberto Lacalle Pou

National Party

29.7029.70

50.7950.79

Ernesto Talvi

Colorada Party

12.8012.80

—

Guido Manini Ríos

Open Cabildo

11.4611.46

—

César Vega

Partido Ecologista Radical Intransigente

1.431.43

—

Edgardo Novick

Partido de la Gente

1.121.12

—

Pablo Mieres

Independent Party

1.011.01

—

Gonzalo Abella

Popular Unity

0.840.84

—

Gustavo Salle

Green Animalist Party

0.830.83

—

Others

Various

0.330.33

—

  • In Round 1, Daniel Martinez led Luis Alberto Lacalle Pou by 10.7910.79 percentage points (40.49%40.49\% vs. 29.70%29.70\%).

  • Prior to Round 2, Lacalle Pou consolidated backing from eliminated candidates (notably Talvi and Manini Ríos), securing 50.79%50.79\% in the runoff to win the presidency.

  • Compared to SMDP, majority-runoff systems expand voter choice in the primary contest while ensuring the eventual winner commands majority backing in the head-to-head runoff.

Proportional Representation: Quota and Divisor Formulas

  • Foundational Principles of Proportional Representation (PR):

    • PR systems operate within multimember districts using either mathematical quotas or divisor algorithms.

    • The core theoretical objective is the proportional reflection of electoral support: a party winning x%x\% of the votes should secure approximately x%x\% of the legislative seats.

    • The two primary sub-types are List PR systems (allocating seats to party slates) and the Single Transferable Vote (STV) (allocating seats directly to candidates via preferential ballots).

  • Mathematical Quotas:

    • A quota defines the exact quantity of votes required to guarantee a single seat in a given district.

    • The general formula for calculating an electoral quota is:

Q(n)=VdMd+nQ(n) = \frac{V_d}{M_d + n}

  • Variable definitions:

    • VdV_d = total number of valid votes cast in district dd.

    • MdM_d = district magnitude (total seats available in district dd).

    • nn = integer modifier determining the quota variant.

  • Standard quota variants include:

    • Hare Quota: n=0n = 0

    • Hagenbach-Bischoff Quota: n=1n = 1

    • Imperiali Quota: n=2n = 2

    • Reinforced Imperiali Quota: n=3n = 3

    • Droop Quota: The Hagenbach-Bischoff quota rounded down to the nearest integer plus one:

QDroop=⌊VdMd+1⌋+1Q_{\text{Droop}} = \left\lfloor \frac{V_d}{M_d + 1} \right\rfloor + 1

  • Seat Allocation via Quotas and the Largest Remainder Method:

    • Stage 1 (Automatic Seats): A party's total district vote is divided by the quota. The integer quotient represents the number of "automatic" seats allocated immediately to that party.

    • Stage 2 (Remainder Allocation): Because integer seat allocations rarely equal the district magnitude (MdM_d), the remaining seats are assigned sequentially to parties possessing the largest fractional remainders of unused votes.

    • Worked Example (Hare Quota with Largest Remainders):

      • District parameters: Md=10M_d = 10 seats; Vd=100,000V_d = 100{,}000 valid votes.

      • Hare Quota calculation:

Q=100,00010+0=10,000Q = \frac{100{,}000}{10 + 0} = 10{,}000

Party

Votes

Votes ÷\div Quota

Automatic Seats

Fractional Remainder

Remainder Seats

Total Seats

Party A

47,00047{,}000

4.704.70

44

0.700.70

11

55

Party B

16,00016{,}000

1.601.60

11

0.600.60

11

22

Party C

15,80015{,}800

1.581.58

11

0.580.58

00

11

Party D

12,00012{,}000

1.201.20

11

0.200.20

00

11

Party E

6,1006{,}100

0.610.61

00

0.610.61

11

11

Party F

3,1003{,}100

0.310.31

00

0.310.31

00

00

Total

100,000100{,}000

—

77

—

33

1010

-   Automatic allocation distributes 77 seats. The remaining 33 seats are awarded to the three largest fractional remainders: Party A (0.700.70), Party E (0.610.61), and Party B (0.600.60).
  • Divisor (Highest Average) Systems:

    • Instead of establishing an absolute quota, a divisor system iteratively divides each party's raw vote total by a predetermined sequence of divisors to produce a matrix of quotients. District seats are assigned one by one to the largest quotients across the matrix.

    • Common divisor sequences:

      • d'Hondt: 1,2,3,4,5,…1, 2, 3, 4, 5, \dots

      • Sainte-Laguë: 1,3,5,7,9,…1, 3, 5, 7, 9, \dots

      • Modified Sainte-Laguë: 1.4,3,5,7,9,…1.4, 3, 5, 7, 9, \dots

    • Worked Example (d'Hondt Seat Allocation):

      • Same baseline data (Md=10M_d = 10 seats, 100,000100{,}000 votes):

Divisor

Party A (47,00047{,}000)

Party B (16,00016{,}000)

Party C (15,80015{,}800)

Party D (12,00012{,}000)

Party E (6,1006{,}100)

Party F (3,1003{,}100)

÷1\div 1

47,00047{,}000 (Seat 1)

16,00016{,}000 (Seat 3)

15,80015{,}800 (Seat 4)

12,00012{,}000 (Seat 6)

6,1006{,}100

3,1003{,}100

÷2\div 2

23,50023{,}500 (Seat 2)

8,0008{,}000 (Seat 9)

7,9007{,}900 (Seat 10)

6,0006{,}000

3,0503{,}050

1,5501{,}550

÷3\div 3

15,66615{,}666 (Seat 5)

5,3335{,}333

5,2665{,}266

4,0004{,}000

2,0332{,}033

1,0331{,}033

÷4\div 4

11,75011{,}750 (Seat 7)

4,0004{,}000

3,9503{,}950

3,0003{,}000

1,5251{,}525

775775

÷5\div 5

9,4009{,}400 (Seat 8)

3,2003{,}200

3,1603{,}160

2,4002{,}400

1,2201{,}220

620620

÷6\div 6

7,8337{,}833

2,6672{,}667

2,6332{,}633

2,0002{,}000

1,0171{,}017

517517

Total Seats

55

22

22

11

00

00

  • Comparative Observation: Under Hare Largest Remainders, Party E (6,1006{,}100 votes) gained a seat through its remainder, leaving Party C with one seat. Under d'Hondt, the final seat (Seat 10) fell to Party C's quotient of 7,9007{,}900, denying Party E a seat. The d'Hondt formula systematically favors larger parties relative to pure quota-remainder systems.

Structural Determinants of Proportionality: Magnitude, Thresholds, and List Types

  • District Magnitude (MM):

    • District magnitude refers to the total number of legislative representatives elected from a single district.

    • Magnitude is the single most critical institutional variable dictating the proportionality of PR systems: as district magnitude increases, proportionality increases, and the barrier to entry for smaller political parties decreases.

    • Empirical variation across states:

      • Single national district (M=total legislatureM = \text{total legislature}): Ukraine utilized a nationwide single district of M=450M = 450 in the 2006 and 2007 parliamentary elections. Serbia currently elects its parliament from a single nationwide district where M=250M = 250.

      • Low-magnitude systems: Chile historically employed a binomial system with M=2M = 2, creating strong majoritarian incentives within a nominally proportional framework.

  • Electoral Thresholds:

    • An electoral threshold specifies the minimum percentage or absolute number of votes a party must attain to be eligible for any legislative seat allocation.

    • Natural (Effective) Threshold: An implicit mathematical threshold inherent to the mechanics of the system, defined primarily by district magnitude (MM) and formula:

Tnatural≈100%M+1T_{\text{natural}} \approx \frac{100\%}{M + 1}

-   **Formal (Legal) Threshold:** A statutory minimum vote share explicitly prescribed in the electoral code (e.g., 5%5\% at the national level).
-   *Negative Consequences of High Thresholds:* Restricting entry via high formal thresholds can disenfranchise large shares of the electorate and distort outcomes:
    -   *Turkey (2002):* A national threshold of 10%10\% resulted in 46%46\% of total votes cast being wasted on parties that failed to pass the threshold.
    -   *Poland (1993):* Strict thresholds led to 34%34\% wasted votes, allowing former Communist successor parties to win a substantial governing majority despite receiving a minority of the popular vote.
  • Party List Types:

    • Closed Party List: The party hierarchy strictly predetermines the internal ranking of its candidates. Electors vote solely for the political party. If a party wins kk seats, the first kk candidates listed on the slate are elected. Voters cannot indicate preference for individual candidates.

Closed list ballot from the historic 1994 South African general election showing party logos, names, and leaders
  • Open Party List: Electors can vote either for the party as a whole or indicate a personal preference for a specific candidate within that party list. Individual candidates amass personal preference votes, which determine their final rank order for seat acquisition.

Danish open list ballot paper from the 2019 Folketingsvalget allowing selection of party slates or specific individual candidates
  • Free Party List (Panachage): Voters possess multiple votes (often equal to district magnitude) that they can distribute flexibly among individual candidates on a single party list, across different party lists (panachage), or accumulate multiple votes on a single favored candidate (cumulation).

The Single Transferable Vote (STV)

  • Core Mechanics and Definitions:

    • The Single Transferable Vote (STV) is the only proportional representation system that does not utilize party lists.

    • STV is a candidate-centered preferential voting system deployed in multimember electoral districts (M≥2M \ge 2).

    • Voters ordinally rank candidates (1,2,3,…1, 2, 3, \dots) across parties or independent candidacies.

    • Any candidate who surpasses a specified quota (typically the Droop quota) of first-preference votes is elected immediately.

    • In subsequent counting rounds:

      • Surplus votes from candidates who exceed the quota are transferred to remaining active candidates in proportion to lower preferences designated on their ballots.

      • If no candidate attains the quota, the lowest-ranking candidate is eliminated, and all their ballots are transferred to designated next preferences.

      • This procedure continues iteratively until all district seats are filled.

  • Comprehensive Worked Example of STV:

    • District Parameters: District Magnitude M=3M = 3; Total Electorate V=20V = 20 voters.

    • Candidates: Bruce, Shane, Sheila, Glen, Ella.

    • Droop Quota Calculation:

Q=⌊203+1⌋+1=5+1=6Q = \left\lfloor \frac{20}{3 + 1} \right\rfloor + 1 = 5 + 1 = 6

-   Each candidate requires exactly 66 votes to win election.
-   *Distribution of Cast Ballots (20 Total):*
    -   44 ballots (Group AAAA): [1] Bruce, [2] Shane, [3] Ella
    -   22 ballots (Group BB): [1] Shane, [2] Bruce, [3] Glen
    -   88 ballots (Group CCCCCCCC): [1] Sheila, [2] Glen
    -   44 ballots (Group DDDD): [1] Sheila, [2] Ella
    -   11 ballot (Group E): [1] Glen
    -   11 ballot (Group F): [1] Ella
  • Step-by-Step Round Progression:

Candidate

Count 1

Count 2 (Surplus Transfer)

Count 3 (Shane Eliminated)

Count 4 (Ella Eliminated)

Final Status

Bruce

44 (AAAA)

44 (AAAA)

66 (AAAA + BB)

66

Elected (Count 3)

Shane

22 (BB)

22 (BB)

Eliminated

—

Eliminated

Sheila

1212 (C… + D…)

66 (Elected)

66

66

Elected (Count 1)

Glen

11 (E)

55 (E + CCCC)

55

55 (Remaining)

Elected (Count 4)

Ella

11 (F)

33 (F + DD)

33

Eliminated

Eliminated

  • Count 1: Sheila receives 1212 first-preference votes (88 from C, 44 from D), surpassing the quota of 66. Sheila is elected with a surplus of 66 votes (12−6=612 - 6 = 6).

  • Surplus Reallocation (Count 2): Sheila's surplus of 66 votes represents exactly 50%50\% of her total vote pool (612=0.5\frac{6}{12} = 0.5). The transfer value applied to all her ballots is 0.50.5:

    • The 88 C ballots transfer 8×0.5=48 \times 0.5 = 4 votes to Glen (indicated as CCCC).

    • The 44 D ballots transfer 4×0.5=24 \times 0.5 = 2 votes to Ella (indicated as DD).

    • Glen now holds 1+4=51 + 4 = 5 votes; Ella holds 1+2=31 + 2 = 3 votes. Bruce has 44; Shane has 22.

    • No remaining candidate meets the quota of 66. The candidate with the fewest votes, Shane (22 votes), is eliminated.

  • Elimination Reallocation (Count 3): Shane's 22 original ballots (Group BB) designate Bruce as second preference. Both ballots transfer to Bruce at full value (+2+2). Bruce reaches 4+2=64 + 2 = 6 votes, matching the quota exactly. Bruce is elected.

  • Final Allocation (Count 4): Bruce has no surplus. Between the remaining un-elected candidates, Glen holds 55 votes and Ella holds 33 votes. Ella is eliminated. Glen is the sole remaining candidate for the third and final seat and is declared elected.

Mixed Electoral Systems: Independent and Dependent Designs

  • Institutional Framework and Electoral Tiers:

    • A mixed electoral system is one in which representatives are elected simultaneously via two distinct systems: one majoritarian and one proportional.

    • Most mixed systems operate across multiple electoral tiers (levels at which votes are aggregated and translated into seats):

      • Lower tier: Single-member district/constituency level (typically employing SMDP majoritarian formulas).

      • Upper tier: Regional or national level (employing List PR proportional formulas).

  • Independent Mixed Systems (Parallel Systems / Majoritarian-Dominant Mixed):

    • Mechanism: The majoritarian and proportional components are executed completely independently of one another. The seat allocation in the proportional tier occurs without regard to seats won by parties in the district majoritarian tier.

    • Worked Model (Independent Mixed System):

      • Assume 55 single-member districts with 5,0005{,}000 voters each (25,00025{,}000 total votes). In every district, Party A wins 3,0003{,}000 votes (60%60\%) and Party B wins 2,0002{,}000 votes (40%40\%).

      • District tier: 55 seats via SMDP. Party list tier: 55 seats via PR allocated nationally.

Party

District Votes Won (Districts 1–5)

National Vote Total

National Vote Share (%)

SMDP Seats Won

List PR Seats Won

Total Seats Won

Total Seat Share (%)

Party A

3,0003{,}000 in each (5×3,0005 \times 3{,}000)

15,00015{,}000

60%60\%

55

33 (60%60\% of 55)

88

80%80\%

Party B

2,0002{,}000 in each (5×2,0005 \times 2{,}000)

10,00010{,}000

40%40\%

00

22 (40%40\% of 55)

22

20%20\%

Total

5,0005{,}000 per district

25,00025{,}000

100%100\%

55

55

1010

100%100\%

-   Outcome: Party A converts 60%60\% of the popular vote into 80%80\% of the total seats (88 out of 1010), preserving substantial disproportionality.
  • Dependent Mixed Systems (Mixed Member Proportional / Compensatory PR):

    • Mechanism: The application of the proportional formula directly depends on the distribution of seats or votes produced by the majoritarian tier. The upper-tier List PR seats are utilized as compensatory "top-up" seats to ensure that each party's total legislative seat share matches its nationwide party list vote share.

    • Dual-Ballot Architecture: Electors cast two separate votes on a split ballot:

      • Electorate / Constituency Vote: A vote for a specific local candidate running in a single-member district.

      • Party List Vote: A vote for a political party slate in the upper tier. The party vote strictly determines the total overall seat entitlement of each party in parliament.

Two-vote ballot paper from New Zealand showing the party list vote on the left and the constituency electorate vote on the right
  • Worked Model (Dependent Mixed System):

    • Identical baseline: Party A wins 60%60\% (15,00015{,}000 votes) and all 55 SMDP districts; Party B wins 40%40\% (10,00010{,}000 votes) and 00 districts. Total legislature = 1010 seats.

    • Total entitlement: Party A is entitled to 60%60\% of 10=610 = 6 total seats. Party B is entitled to 40%40\% of 10=410 = 4 total seats.

Party

National Vote Total

National Vote Share (%)

Total Seat Entitlement

SMDP District Seats Won

Compensatory List PR Seats

Final Total Seats Won

Final Total Seat Share (%)

Party A

15,00015{,}000

60%60\%

66

55

11 (6−56 - 5)

66

60%60\%

Party B

10,00010{,}000

40%40\%

44

00

44 (4−04 - 0)

44

40%40\%

Total

25,00025{,}000

100%100\%

1010

55

55

1010

100%100\%

  • Outcome: In the dependent mixed framework, the List PR tier neutralizes the majoritarian bias created in the district contests, yielding a final seat distribution that is strictly proportional to overall popular support.