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Longevity Risk Intelligence

Price the path,
not the endpoint.

Two mortality trajectories with identical starting and terminal values can differ in economic consequence by up to 8% of portfolio value. Every traditional model misses this. Eld does not.

Compute time 3.43s
Monte Carlo paths 100,000
Path premium captured up to 8%
Pension Risk TransferPRT
Longevity Swap PricingPath-Dependent
Solvency II SCREnhanced
Buy-In / Buy-OutReal-Time Quotes
IFRS 17 Risk AdjustmentCompliant
ILS Tranche StructuringSecuritisation
Mortality Hedge RatiosMalliavin
Wasserstein DRRORobust
Pension Risk TransferPRT
Longevity Swap PricingPath-Dependent
Solvency II SCREnhanced
Buy-In / Buy-OutReal-Time Quotes
IFRS 17 Risk AdjustmentCompliant
ILS Tranche StructuringSecuritisation
Mortality Hedge RatiosMalliavin
Wasserstein DRRORobust

Survival is a path-dependent functional.
Actuarial practice treats it as though it is not.

The survival probability ₜpₓ = exp(−∫μₛ ds) depends on the integrated mortality path, not its endpoint. When a mortality spike arrives early — against small reserves — it carries materially different consequences than the same spike arriving late against accumulated capital.

Standard actuarial models assess longevity risk using terminal-value objectives. They cannot distinguish these scenarios. Eld encodes the full path through the log-signature transform from rough path theory, capturing mortality timing, return-reserve correlation, and basis risk exposure that terminal values cannot see.

The result: path-dependent effects worth up to 8% of portfolio value, previously invisible, now priceable in seconds.

The central insight — illustrated

Same start. Same end. Different price.

Both scenarios: µ₀ = 0.020, µᵀ ≈ 0.020, identical terminal reserves. Yet they are not the same.

Scenario A — Early shock
Adverse
t=1yr shock reserves µ(t)
Shock timingYear 1
Reserve at shock£1,000
Mortality-weighted PVLower
Scenario B — Late shock
Benign
t=7yr shock reserves µ(t)
Shock timingYear 7
Reserve at shock£1,400
Mortality-weighted PVHigher
Value difference — terminal objectives cannot see this
up to 8%
of portfolio value
systematically missed
Eld quantifies it in
3.43s
100,000 Monte Carlo paths
0s
Full pricing cycle
End-to-end path-dependent computation. 100,000 Monte Carlo paths. GPU-parallel. Against the industry standard of days to weeks.
0%
Path premium captured
Bottom-decile path premium: £167.3m on a £2.1bn portfolio. Invisible to terminal-value models. Explicit in Eld.
0×
Computational speedup
Against single-threaded CPU baseline. Adjoint gradient method achieves O(MD²) complexity independent of control parameters.
0
Robustness levels
Doubly robust: Wasserstein distributional uncertainty and ellipsoidal preference uncertainty. Hedged against both simultaneously.
Methodology

Three mathematical traditions. One unified framework.

Layer 01 — Encoding

Log-signature transform

Rough path theory encodes your mortality trajectory into log-signature components. Each captures what terminal values cannot: timing, correlation between mortality and reserves, basis risk exposure.

L²(t,μ) ← time-weighted
           mortality exposure
L²(R,S) ← return-reserve
           correlation
L²(μ,S) ← mortality-reserve
           interaction
Layer 02 — Optimisation

Doubly robust DRRO

Wasserstein distributionally robust regret optimisation. Hedges against distributional misspecification without the over-conservatism of standard robust methods. Measures performance against the best alternative policy, not absolute worst-case.

DRRO: inf sup sup
  c∈C μ∈Bᵟ β∈C
  [Eμ[α⊤φ(Lᵝ)]
   − Eμ[α⊤φ(Lᶜ)]]
Layer 03 — Computation

Two-level adjoint transport

Gradients propagate backward through Baker–Campbell–Hausdorff compositions. O(MD²) complexity, independent of the number of controls. GPU-parallel across Monte Carlo paths. The same infrastructure runs both optimisation and hedging.

λᵢ = J₁(Qᵢ,Sᵢ)⊤ λᵢ₊₁
∂V/∂Qᵢ = J₂(Pᵢ₋₁,Qᵢ)⊤ λᵢ
O(MD²) · independent
         of K controls
"Terminal-value optimisation is not merely an approximation of the true objective. It is a category error — one that systematically ignores the path structure central to longevity risk."
From the Eld methodology paper · January 2026
Who uses Eld

Built for institutions where longevity risk is the risk.

Reinsurance

Life reinsurers pricing pension risk transfer

Quote generation that once required days of actuarial team time completes in seconds. Path-dependent pricing captures timing effects that standard models miss, enabling more accurate premiums and a competitive edge in the PRT market.

Bulk annuity pricing · Q-forward valuation
Longevity swap structuring · Real-time quotes
Pension Schemes

Defined benefit schemes assessing buy-in value

Understand the path premium in your own liability portfolio before entering a buy-in negotiation. Know what your trustees are paying for — and what the insurer's terminal-value model cannot see that yours can.

Liability path analysis · Funding ratio monitoring
Solvency II SCR · IFRS 17 risk adjustment
ILS / Capital Markets

ILS structurers building longevity tranches

Percentile tranche valuation with path-dependent survival probability computation. The max-affine structure of tranche payoffs maps directly onto Eld's log-signature framework — no approximation required.

Percentile tranching · Longevity securitisation
Tranche sensitivity · Basis risk quantification
Quantitative Research

Actuarial quants building internal models

API access to Eld's computation engine. Run path-dependent pricing inside your own models. Malliavin-based hedge ratios computed in a single backward pass rather than O(M) forward passes. Full Solvency II internal model documentation.

REST API · JAX-compatible · GPU-parallel
Malliavin Greeks · Adjoint differentiation
Platform — What you get
Ringmark Dashboard
Live monitoring of L²(t,μ) exposure, return-reserve correlation, and path premium across your portfolio. Updated continuously.
Real-time pricing engine
Path-dependent bulk annuity and longevity swap pricing. 3.43 seconds for 100,000 Monte Carlo paths on GPU. No batch queue.
Layerstone scenarios
DRRO sensitivity analysis across uncertainty radii. Compare robust versus ERM policies. Explicit preference uncertainty modelling.
Duramen securitisation
Percentile tranche valuation and ILS structuring. Max-affine payoff handling. Path-dependent survival probability encoding.
Malliavin hedge ratios
Full mortality hedge ratio computation via adjoint-Malliavin correspondence. Single backward pass replaces O(M) finite-difference calls.
Aldfen API
Programmatic access to the full computation engine. Embed Eld's path-dependent pricing inside your own actuarial models and workflows.
Regulatory outputs
Solvency II SCR, IFRS 17 risk adjustment, UK matching adjustment quality metrics — all path-enhanced, audit-ready.
Varve audit trail
Every calculation logged, traceable, and immutable. Built for internal model approval and regulatory review.
Basis risk quantification
L²(μ,S) monitoring measures how mortality changes interact with reserve levels in real time. The basis risk that standard models cannot see.

Your mortality model
sees the endpoint.
See the path.

No sales process. No consulting relationship required. Upload a cohort, run a pricing cycle, see the path premium your current model cannot find.

Try Eld — it's free Read the methodology paper
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