# DFI Gerrymandering Assessment Guide

## Overview and Purpose

The **Democratic Fitness Indicator (DFI)** measures how effectively citizens can exercise democratic power. Gerrymandering—the manipulation of electoral district boundaries—can significantly distort democratic representation. Even without partisan intent, certain electoral systems may produce mathematical outcomes that don't reflect voter preferences accurately.

This guide helps researchers assess gerrymandering through two key metrics:
1. **Efficiency Gap** (60% weight) - measures partisan vote advantage
2. **Seats-Votes Asymmetry** (40% weight) - measures disproportionality

**Important:** For countries with bicameral legislatures, each chamber must be assessed separately as they often use different electoral systems with varying vulnerability to gerrymandering.

## Step 1: Determine System Vulnerability

### 1.1 Identify Your Country's Legislative Structure

First, determine whether your country has:
- **Unicameral legislature** (one chamber) → Assess that single chamber
- **Bicameral legislature** (two chambers) → Assess EACH chamber separately

### 1.2 Classify Electoral System Vulnerability

For each chamber, determine if the electoral system is vulnerable to gerrymandering:

#### Vulnerable Systems
- **Single-Member District Systems** (First-Past-The-Post, Two-Round Systems)
- **Mixed Electoral Systems** with single-member district components
- **Block Voting Systems** with multi-member districts
- Any system where electoral boundaries can be redrawn for electoral purposes

#### Non-Vulnerable Systems  
- **Pure Proportional Representation** with nationwide constituency
- **List PR systems** with fixed administrative boundaries
- **Single Transferable Vote (STV)** with fixed administrative units
- **Appointed or indirectly elected chambers**

### 1.3 Document Your Assessment

**For Unicameral Systems:**
```
COUNTRY: [Name]
ELECTORAL SYSTEM: [Type]
VULNERABILITY TO GERRYMANDERING: [None/Low/Moderate/High]
RATIONALE: [Brief explanation]
```

**For Bicameral Systems:**
```
COUNTRY: [Name]
BICAMERAL SYSTEM: Yes

LOWER HOUSE ([Name]):
- Electoral System: [Type]
- Vulnerability: [None/Low/Moderate/High]
- Rationale: [Brief explanation]

UPPER HOUSE ([Name]):
- Electoral System: [Type]
- Vulnerability: [None/Low/Moderate/High]
- Rationale: [Brief explanation]

PROCEED WITH DATA COLLECTION FOR:
- Lower House: [Yes/No]
- Upper House: [Yes/No]
```

## Step 2: Handle Non-Vulnerable Systems

If a chamber is NOT vulnerable to gerrymandering, document this finding and skip to Step 5.

**Documentation for Non-Vulnerable Chambers:**
```
CHAMBER: [Name]
ELECTORAL SYSTEM: [Type]
STANDARD METRICS NOT APPLICABLE DUE TO: [Explanation]

ALTERNATIVE ASSESSMENT:
- [Consider reporting on malapportionment if relevant]
- [Note any other electoral distortions present]
- [Reference Gallagher Index or other appropriate metrics]

DFI CLASSIFICATION: Minimal (by definition for non-vulnerable systems)
```

## Step 3: Collect Data for Vulnerable Chambers

**Only proceed with data collection for chambers identified as vulnerable in Step 1.**

### Required Electoral Data

For each vulnerable chamber, collect from the most recent election:

#### District-Level Data (ESSENTIAL)
- District name/identifier
- Total votes cast per district
- Votes received by each major party (>2% national share)
- Winning party and margin

#### National Summary
- Total votes by party (nationwide)
- Total seats won by party
- National vote percentage by party
- National seat percentage by party

### Data Collection Strategy

1. **Primary Sources**
   - Official election commission websites
   - Look for "constituency results" or "district results"
   - Check for downloadable datasets (CSV, Excel, XML)
   - Search in the local language (e.g., for Poland: "wyniki wybory okręgi")

2. **If Online Summaries Are Incomplete**
   - Look for official PDF reports with detailed annexes
   - Check for academic databases with compiled results
   - Contact the electoral commission directly
   - Search for open data portals

3. **Verification**
   - Ensure you have results for ALL districts
   - Verify district totals sum to national totals
   - Check that seat allocations match official results

### When District-Level Data is Unavailable

**If you cannot obtain complete district-level vote data after thorough search:**

**Option A: Use Secondary Sources**
- Search for academic studies that have already calculated these metrics
- Check electoral integrity reports from organizations like:
  - International IDEA
  - Electoral Integrity Project
  - OSCE/ODIHR election reports
- Clearly cite these secondary calculations

**Option B: Partial Assessment with Available Data**
If district-level data is unavailable but you have national-level data:
- Calculate only the Seats-Votes Asymmetry metric (requires only national vote shares and seat totals)
- Clearly note that assessment is based on one metric only
- Document why the Efficiency Gap cannot be calculated

```
DATA LIMITATION:
District-level vote data unavailable - cannot calculate Efficiency Gap
Assessment based on Seats-Votes Asymmetry only

SEATS-VOTES ASYMMETRY: [Calculate using national data]
- Party A: X% votes, Y% seats = Z% asymmetry
- Party B: X% votes, Y% seats = Z% asymmetry
Maximum asymmetry: [Highest value]

PARTIAL DFI CLASSIFICATION: [Based on asymmetry only]
- Severe: >20% asymmetry  
- Limited: 10-20% asymmetry
- Minimal: <10% asymmetry

NOTE: This classification is based on one metric only. Full assessment requires district-level data for Efficiency Gap calculation.
```

**Option C: Document Complete Data Limitation**
If neither district-level nor national vote share data is available:
```
DATA AVAILABILITY LIMITATION:
Complete district-level vote data unavailable after searching:
- [List sources checked]
- [Languages searched]
- [Datasets examined]

National vote share data also unavailable

UNABLE TO CALCULATE: Both Efficiency Gap and Seats-Votes Asymmetry
RECOMMENDATION: Metrics require vote data for calculation
```

**IMPORTANT:** Never estimate or approximate these metrics. Either calculate them with available data (noting limitations) or report inability to calculate.

## Step 4: Calculate Metrics for Each Vulnerable Chamber

**Only proceed if you have complete district-level data for ALL districts.**

### 4.1 Efficiency Gap Calculation

```
For each district:
1. Identify winner and their vote total
2. Calculate wasted votes:
   - Winning party: (Winner's votes) - (Total votes ÷ 2 + 1)
   - Losing parties: All their votes

For the nation:
3. Sum wasted votes by party
4. Calculate: |Party A wasted - Party B wasted| ÷ Total votes
5. Convert to percentage
```

**Example:**
- Party A total wasted votes: 500,000
- Party B total wasted votes: 300,000
- Total votes cast: 2,000,000
- Efficiency Gap = |500,000 - 300,000| ÷ 2,000,000 = 10%

### 4.2 Seats-Votes Asymmetry Calculation

```
For each major party:
1. Vote share = Party votes ÷ Total votes × 100
2. Seat share = Party seats ÷ Total seats × 100
3. Asymmetry = |Seat share - Vote share|
4. Report the HIGHEST asymmetry among all parties
```

**Example:**
- Party A: 45% votes, 55% seats → 10% asymmetry
- Party B: 40% votes, 35% seats → 5% asymmetry
- Party C: 15% votes, 10% seats → 5% asymmetry
- Maximum asymmetry = 10%

### 4.3 Combined Score and Classification

```
Combined Score = (Efficiency Gap × 0.6) + (Seats-Votes Asymmetry × 0.4)
```

**Classification Thresholds:**
- **Severe**: Combined score >15%
- **Limited**: Combined score 7-15%
- **Minimal**: Combined score <7%

## Step 5: Report Your Findings

### For Countries with One Vulnerable Chamber

```
COUNTRY: [Name]
CHAMBER: [Name if bicameral]
ELECTION: [Date/Year]
ELECTORAL SYSTEM: [Type]

EFFICIENCY GAP: [X.X%]
SEATS-VOTES ASYMMETRY: [X.X%]
COMBINED SCORE: [X.X%]
DFI CLASSIFICATION: [Severe/Limited/Minimal]

DATA SOURCES:
- [Source 1 with URL]
- [Source 2 with URL]

DATA NOTES:
- [Any important considerations]
```

### For Countries with Two Vulnerable Chambers

```
COUNTRY: [Name]
ELECTION: [Date/Year]

LOWER HOUSE: [Name]
ELECTORAL SYSTEM: [Type]
EFFICIENCY GAP: [X.X%]
SEATS-VOTES ASYMMETRY: [X.X%]
COMBINED SCORE: [X.X%]
DFI CLASSIFICATION: [Severe/Limited/Minimal]

UPPER HOUSE: [Name]
ELECTORAL SYSTEM: [Type]
EFFICIENCY GAP: [X.X%]
SEATS-VOTES ASYMMETRY: [X.X%]
COMBINED SCORE: [X.X%]
DFI CLASSIFICATION: [Severe/Limited/Minimal]

WEIGHTED ASSESSMENT FOR DFI:
[Apply 70% weight to lower house, 30% to upper house]

DATA SOURCES:
- [Source 1 with URL]
- [Source 2 with URL]
```

### For Mixed Vulnerability (One Vulnerable, One Not)

```
COUNTRY: [Name]

[VULNERABLE CHAMBER]: [Name]
ELECTORAL SYSTEM: [Type]
EFFICIENCY GAP: [X.X%]
SEATS-VOTES ASYMMETRY: [X.X%]
COMBINED SCORE: [X.X%]
DFI CLASSIFICATION: [Severe/Limited/Minimal]

[NON-VULNERABLE CHAMBER]: [Name]
ELECTORAL SYSTEM: [Type]
VULNERABILITY: None - [System type] prevents gerrymandering
[Include any alternative assessment if relevant]

DATA SOURCES:
- [Source 1 with URL]
- [Source 2 with URL]
```

### When Data is Unavailable

```
COUNTRY: [Name]
CHAMBER: [Name]
ELECTORAL SYSTEM: [Type]

DATA AVAILABILITY LIMITATION:
Complete district-level vote data unavailable after searching:
- Sources checked: [List all attempted sources]
- Search languages: [Languages used]
- Barrier encountered: [e.g., paywall, non-digital format, not published]

ALTERNATIVE ASSESSMENT:
[If available from secondary sources, cite the calculated metrics]
[Otherwise, note qualitative observations about the electoral system]

DFI CLASSIFICATION: Unable to calculate - requires district-level data

RECOMMENDATION: Further investigation needed with access to [specific data source]
```

## Common Data Challenges and Solutions

### Challenge: Only seat results available, no vote totals
**Solution:** This is insufficient. Document the limitation and seek vote data from:
- Electoral commission archives
- Academic researchers who study this country
- International election observation reports

### Challenge: Partial data (some districts missing)
**Solution:** Do not calculate with incomplete data. Either:
- Find the missing districts
- Report "Unable to calculate - incomplete data"

### Challenge: Data in non-machine readable format
**Solution:** 
- Check if the electoral commission has a data portal
- Look for civil society organizations that digitize results
- Consider whether manual data entry is feasible for the number of districts

### Challenge: Different sources show conflicting numbers
**Solution:**
- Prioritize official electoral commission data
- Document any discrepancies found
- Use the official results even if other sources seem more complete

## Special Considerations

### Mixed Electoral Systems
- For parallel systems: analyze only the single-member district portion
- For MMP systems: if compensatory, classify as non-vulnerable
- Calculate metrics based only on SMD seats, not the PR portion

### Strategic Voting Effects
- Electoral pacts (like Poland's Senate Pact) affect efficiency gap
- Document strategic coordination but calculate metrics based on actual results
- Note when results reflect strategy rather than boundaries

### Upper Houses with Fixed Boundaries
- If boundaries are constitutional (states/provinces), apply only District Type evaluation
- Skip efficiency gap and asymmetry calculations for fixed territorial units

### Temporal Considerations
- Always use the most recent complete election cycle
- If chambers elected at different times, use their respective most recent elections
- Document any temporal differences clearly

## Common Pitfalls to Avoid

1. **Don't estimate** metrics when data is unavailable
2. **Don't assume** both chambers use the same electoral system
3. **Don't mix** data from different election types or years
4. **Don't include** appointed seats in calculations
5. **Don't calculate** metrics for PR systems—they're not applicable
6. **Don't use** partial data—all districts must be included
7. **Don't combine** chambers into one calculation—assess separately

## Quick Reference: Vulnerability Decision Tree

```
Is the chamber directly elected?
├─ NO → Not vulnerable (skip assessment)
└─ YES → What electoral system?
    ├─ Single-member districts → VULNERABLE
    ├─ Mixed system → Check if compensatory
    │   ├─ Compensatory (MMP) → Not vulnerable
    │   └─ Parallel → SMD portion is VULNERABLE
    └─ Proportional representation → Not vulnerable
```

## Data Quality Checklist

Before calculating metrics, verify:
- [ ] Have results for ALL districts in the chamber
- [ ] Vote totals for each party in each district
- [ ] District totals sum to national totals
- [ ] Using the most recent election data
- [ ] Data comes from authoritative source
- [ ] No districts are missing or show zero votes
- [ ] Winning party is identified for each district

If any item is unchecked, do not proceed with calculations.

---

*Remember: The goal is to measure mathematical disproportionality, not to determine intent. High efficiency gaps or asymmetry indicate distorted representation regardless of whether boundaries were deliberately manipulated.*