Summary
We built an agent-based model (ABM) of the Regen token economy to test how issuance, burns, rewards, and liquidity interact with eco-credit demand. We ran baselines, parameter sweeps, and stress tests to find policy regions that increase timely retirements while keeping security and liquidity healthy. The result is a governance-ready menu of parameter ranges, code, and reproducible experiments.
Demo session recording:
Key Findings
- Higher burn share reduces net inflation and shortens retirement lag, but validator rewards need a protected APR floor and sufficient AMM depth.
- Maintaining liquidity depth during shocks reduces slippage and preserves price stability more than increasing issuance alone.
- Parameter regions exist where retirements grow faster than issuance without harming validator security, especially when regrowth “r” is capped and AMM rewards are targeted.
Policy Takeaways
- Cap regrowth r within a defined band and route a share of rewards to AMM depth to offset higher burn share.
- Maintain validator APR within a floor range in shocks to prevent security erosion.
- Use an efficient-frontier plot (retirements up vs inflation down) to anchor governance choices.
Problem and Approach
Problem Definition
Core problem: Identify issuance and scarcity policies for $REGEN that most reliably increase timely retirement of eco-credits relative to issuance, while maintaining token security, liquidity, and governance feasibility.
Key questions:
- What funding distribution to activities (liquidity, credit curation, creation) yields the highest marginal ecological plus economic benefit per $REGEN?
- Which parameter ranges for regrowth r, burn share, validator APR, and caps minimize net inflation while maximizing retirement rate and reducing retirement lag?
- How do shocks to liquidity, validator set, or eco-credit demand propagate through staking, prices, and retirements?
Why ABM
- Heterogeneity: Delegators, speculators, issuers, LPs, validators act with different rules and constraints.
- Feedbacks and path dependence: Burns on retirements, staking incentives, and liquidity co-evolve with demand, creating non-linear dynamics that static methods miss.
- Policy exploration under uncertainty: Monte Carlo and stress tests across many micro-rules reveal robust policy regions, not single “optimal” points.
Environment and Interactions
- Environment: Markets for $REGEN spot, staking, and eco-credits. Treasury/policy module applying issuance regrowth, burns, fees. Exogenous demand processes for eco-credits and liquidity shocks.
- Interactions: Agents submit orders, staking changes, issuance and retirement events. The environment clears markets, updates prices, applies burns and regrowth, and updates validator/security metrics.
Data and Metrics
Data Sources
- On-chain: Staking ratios, validator sets, APRs, churn, slashing events. Token price and volume histories. Liquidity depth metrics.
- Registry and market data: Eco-credit issuance and retirement time series by category and size. Retirement lag distributions.
- External analogs: ETH post-EIP-1559 burn dynamics, Cosmos staking participation, comparable carbon markets for demand regimes.
KPIs
- Ecological: retirement rate and lag, issued vs retired, issuance-to-retirement ratio
- Economic: net inflation, price stability, AMM depth, slippage, fee accrual
- Security and participation: staking share, validator APR, churn
- Distribution: ownership concentration and Gini coefficient
Model Overview
Agents and Roles
- Fund/treasury: mints, splits rewards between holders and AMM, optional sell policy.
- Holders: hodlers, validators (rewarded), traders (biased micro-flows).
- Liquidity providers and AMM: constant-product pool with fees and optional external LP in/out.
- Issuers: create and retire eco-credits.
Key Parameters and Policies
- Issuance regrowth r, burn share, reward splits (holders vs AMM), validator APR target band, fee bps.
- Demand: initial external demand in $, elasticity, growth rate, per-tick cap.
Safety Guards
- Max trade fraction of pool per tick.
- Demand cap fraction to bound exogenous buy-and-burn.
- Oracle smoothing to reduce noise.
Experiments
Baselines
Low demand, high demand, validator drop, LP shock.
Parameter Sweeps
- r ∈ [0.01–0.15], burn_pct ∈ [0.1–0.5], validator APR ∈ [5–20%], elasticity bands.
- Monte Carlo runs (N=100 per scenario).
Stress Tests
- Liquidity shock (–50% LPs)
- Validator exit (top decile)
- Eco-credit boom/drought
How to Run It Yourself
Run the NetLogo prototype at: https://www.netlogoweb.org/launch#Load
Set sliders: initial-price, issuance-rate, distribution-fraction-of-mint, amm-fee-bps, demand-elasticity, external-lp-flow, etc. Click Setup → Go. Watch price, TVL, cumulative minted/burned.
Results and Interpretation
Tools
- Fidelity vs speed: NetLogo for prototyping behaviors and UI; cadCAD for batch experiments and Monte Carlo.
- Reproducibility: notebooks, seeds, CSV outputs.
- Communication: dashboard built with Replit made findings interactive, but infra costs (~$10/day) pushed us back to a video + source release.
Limitations
- Single-pool AMM, stylized demand, simplified heterogeneity.
- No explicit cross-venue fragmentation or cross-chain arbitrage (can be added as network topology later).
Governance Implications
Policy Menu Candidates
- Issuance regrowth r bands that avoid runaway inflation under typical demand.
- Reward split ranges that maintain validator APR while preserving AMM depth.
- Fee bps guidance to support TVL and reduce slippage without killing flow.
Decision Aid
Show an “efficient frontier” plot: ecological retirements up vs inflation down. Use it to select parameter bands that meet minimum validator APR and liquidity depth thresholds.
Possible Next Steps
- Calibrate with Regen on-chain and registry datasets; publish parameter bands with confidence intervals.
- Propose a phased pilot: adopt conservative r and burn_pct bands with monitoring triggers and explicit rollback conditions.
References
- NetLogo prototype: https://www.netlogoweb.org/launch#Load
- Macal & North (2010) ABM tutorial: https://faculty.sites.iastate.edu/tesfatsi/archive/tesfatsi/ABMTutorial.MacalNorth.JOS2010.pdf