7 Equivalent and Reduced Models

Learning Objectives

By the end of this chapter, you will be able to:

Derive the sire model and state the assumptions that make it an approximation
Relate sire EBVs to animal-model EBVs computed on the same data
Build the sire–maternal grandsire relationship matrix and its inverse
Set up a reduced animal model and back-solve for non-parents
Judge when a reduced model is worth the information it discards

Assumes Ch 6.

Chapter in progress

This chapter has not been written yet. The objectives above are the contract it will be written against — they are taken from CHAPTERS.md, which is the outline for the whole book.

Purpose. Sire, sire–MGS, and reduced animal models, framed as data reduction and model equivalence rather than as a step backward.

---
title: "Equivalent and Reduced Models"
---

::: {.callout-note icon=false}
## Learning Objectives

By the end of this chapter, you will be able to:

1. **Derive** the sire model and state the assumptions that make it an approximation
2. **Relate** sire EBVs to animal-model EBVs computed on the same data
3. **Build** the sire–maternal grandsire relationship matrix and its inverse
4. **Set** up a reduced animal model and back-solve for non-parents
5. **Judge** when a reduced model is worth the information it discards
:::

*Assumes Ch 6.*

::: {.callout-warning}
## Chapter in progress

This chapter has not been written yet. The objectives above are the contract it will be written
against — they are taken from `CHAPTERS.md`, which is the outline for the whole book.

**Purpose.** Sire, sire–MGS, and reduced animal models, framed as data reduction and model equivalence rather than as a step backward.
:::