lazyeconomist.com · 005 · Glidepath Lab

Glidepath Lab

Live · v0.4.0 Engine, API and workbench

A simulator for a private-markets sleeve inside a target-date glidepath: retirement income across a grid of return premiums, plan-level cash flows against the vehicle's redemption cap, the fee hurdle the sleeve must clear, and a six-factor memo that sets that evidence out for a fiduciary — and leaves the judgement to the committee.

Open the workbench → Read the introduction

No sign-in needed. Anonymous runs are demo mode: up to 500 paths, two stress scenarios, premiums to +3 pp, nothing stored. Signed-in runs are saved.

Retirement income by entry age at two premiums against the no-sleeve baseline
The demo plan, 500 paths: median retirement income by cohort entry age with the sleeve at +0 and +2 percentage points of premium, 5th–95th percentile bands, against the dashed no-sleeve median. The premium is a scenario, not a constant; liquidity is a plan-level property; the deliverable is a versioned record, not an optimal weight.
Workbench

Build, run, read

A plan from cited defaults, four private sleeves, the fan charts, the liquidity dashboard, the fee panel and a shareable link.

API

The same engine over JSON

POST a run document, poll for the summary. Interactive documentation at /docs.

Scenarios

Seven stress tests

From the 2022 denominator drift to a BCRED-style gate, each described with what the engine actually does.

Methodology

Paper 1 of 3

An introduction to the methodology

Paper 2 of 3

Technical note: equations, defaults and tests

Paper 3 of 3

Frequently asked questions

The six-factor memo generator is live. It turns a saved run into a versioned document organised around the six factors — performance, fees, liquidity, valuation, benchmarking and complexity — where every sentence is derived from that run by rule, anything the plan record does not carry is named as pending rather than filled in, and each section ends in an empty note for the committee's own words. It reaches no conclusion and makes no recommendation: it assembles the evidence and asks the questions.