The words the model actually uses

Terms

Ensemble

The set of futures a single run produces. Each one starts from the same world and meets a different sequence of shocks and a different draw of the uncertain coefficients. 250 is the default.

Path

One future inside the ensemble. A path is a complete run of the model from the base year to the horizon.

Seed

The number that fixes which shocks happen in which years. Two scenarios run on the same seed meet identical luck, so the difference between them is your lever rather than the noise.

Common random numbers

The technique behind that. Each random draw is addressed by the year, the country and the channel it belongs to rather than pulled in sequence, so adding a lever cannot shift the luck of everything after it.

Branch

A cluster of paths that ended up in a similar place. Each branch is reported with the share of the ensemble that landed in it, which is the closest thing here to a probability.

Horizon

How many years forward a run goes. Longer horizons are not more knowledge, they are more compounding of the same assumptions, and the confidence panel says so.

Lever

A change you make to the world. 27 of them, from a tariff on one pair of countries to a worldwide carbon price. Each has a start year, a duration and a phase in.

Coalition

A group acting as one. A lever imposed by the G7, the EU or NATO applies from every member at once, and the load on the target is weighted by the share of world output imposing it.

Channel

The route a shock travels: trade, energy, money, people, capability, alignment, inputs. The causes panel is organised by channel.

Contribution

A named term inside a headline number. Growth is built as the sum of eleven of them, inflation nine, unemployment five. They add up exactly, which is what makes the drill down honest.

Provenance

What kind of number a data point is. Curated means entered by hand from a source. Partial means some fields were. Patterned means inferred from region, income tier and structure. Sourced means pulled from the World Bank with its year attached.

Potential output

What an economy could produce at full employment. The gap between actual and potential drives inflation and unemployment, and closes slowly through hysteresis.

Gravity trade

The model of who trades with whom: bigger economies closer together trade more. Each country keeps its top partners and the weights are renormalised, which is what makes 238 countries run in seconds.

Sensitivity

How much the answer moves when one uncertain parameter moves. The confidence panel ranks the parameters by how much of the spread each one is responsible for.

Analogue

A historical episode scored against your run on nine features. Not a claim that history repeats, a way to ask whether the model has put you somewhere that has happened before.

Seed

The number that decides which shocks are drawn in which years. Two runs on one seed meet the same luck, so the difference between them is what you changed. Change the seed and you can no longer say that.

Horizon

How many years a run covers. The band widens with every year of it, so a longer horizon does not give you more answer, it gives you a wider one.

Quantile

A value the ensemble is split at. The tenth quantile is the figure a tenth of the futures came in below. The bands on every fan chart are the tenth to ninetieth and the twenty fifth to seventy fifth.

Branch

A family of futures that resemble each other, found by clustering the ensemble on how each future ended. The share beside a branch is the fraction of the ensemble that landed in it.

Reference column

On the comparison page, the scenario everything else is measured against. It is a choice rather than whichever run was kept first, because the interesting comparison is rarely against the oldest one.

Provenance

Where a figure came from, marked on every row: curated, partial or patterned for the base year data, and measured, curated, derived or modelled across the whole instrument.

Composite index

A weighted sum of seven terms over measured and modelled inputs, such as instability or resilience. The weights are published, they sum to one, and clicking the index opens its arithmetic.

Flow

A quantity moving between two countries, drawn as an arc. Thirteen kinds, each readable as gross, net or by direction, and groupable by bloc, region, alliance or partner.

Overlay

Anything drawn on top of the base layer: cables, pipelines, satellites, protests, chokepoints. Any number can be on at once, which is the point of the panel.

Base layer

The single field that colours the countries themselves. One at a time, because two colours on one shape is not a reading.

Lever

A change you make to the world before the run: a tariff, an export control, a rate move, a subsidy, a treaty. Forty four of them, each with a real channel into the engine and a cost paid out of the same budget.

Channel

The specific route by which a lever reaches an outcome. A tariff reaches growth through import prices, through trade volumes and through the counterparty's reply, and those are three channels rather than one effect.

Retaliation

A government answering a tariff or a control in kind. It is drawn per future with a probability rather than applied automatically, which is why two futures with the same lever can diverge sharply.

Build lag

The years between a capacity decision and the capacity existing. Fabs take four years in the model and energy takes three, so a subsidy set in year one does nothing visible until year five.

Anchoring

How firmly inflation expectations stay near target when prices move. It is one of the drawn parameters, and it is very often the single biggest contributor to the spread on an inflation question.

Hysteresis

Damage that does not heal when the cause goes away. Unemployment that persists after output recovers is the clearest case, and it is why the order of events in a run matters.

Chokepoint

A strait or canal that a large share of world trade must pass through. Thirteen of them are carried, with what moves through each, because a great deal of trade risk is geography rather than policy.

Two line element

The seven numbers that describe a satellite's orbit, published by CelesTrak. Positions are propagated from them in your browser by the standard near-earth model rather than fetched.

Kp index

The planetary geomagnetic index, on a scale to nine. Above five the upper atmosphere expands and drag rises on everything in low orbit, which is the one live reading that touches another layer.

Confidence score

A deduction from a hundred with every deduction named: band width, horizon length, parameter share and analogue distance. It says how much the model knows about its own answer, not how likely the answer is.