---
title: "ModelFamily"
description: "one family of quantitative model a market may be expressed in over the substrate: what it represents, the quantities it holds, what it reads from the record, what it gives, the solver that steps or solves it, and the check that proves it; a template names its family and a vertical chooses among them"
section: concepts
address: /concepts/modelfamily
contract: 0476e35e6e275db5
---

# ModelFamily

one family of quantitative model a market may be expressed in over the substrate: what it represents, the quantities it holds, what it reads from the record, what it gives, the solver that steps or solves it, and the check that proves it; a template names its family and a vertical chooses among them

[figure: ModelFamily is a row at platform scope. The drawing shows its fields and the objects that they point at.]

| property | value |
|---|---|
| kind | row |
| scope | platform |
| key | its name |
| store | postgres |
| family | market |



## Fields


| field | type | required | note |
|---|---|---|---|
| `name` | `text` | yes |  |
| `what` | `text` | yes |  |
| `representation` | `one of stocks and flows \| a graph of participants and handovers \| a hypergraph of co-presence \| agents with behaviours \| a game of roles \| a learned latent model of the market` | yes |  |
| `substrate` | `text` | yes | the parts of the platform the model is written over and stepped on |
| `state_form` | `text` | yes | what one state of the model is, as rows |
| `quantities` | `[text]` | yes | the quantities the model holds, each a registered measure or a parameter |
| `reads` | `[text]` | yes | what it reads from the record, by kind |
| `gives` | `[text]` | yes | what a run gives, by kind |
| `solver` | `text` | yes | how a state becomes the next, or how the model is solved |
| `check` | `text` | yes | the check that proves a run right, with its planted fault |
| `fits_verticals` | `[text]` | yes | the vertical families it fits, by name; empty means every vertical |



## Routes that use it
No route takes or returns ModelFamily directly. The record holds it, and the objects that point at it reach it.