14 Threshold Models for Categorical Traits

Learning Objectives

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

Explain the liability concept and the threshold model
Set up a threshold model for a binary trait and solve it iteratively
Extend to more than two ordered categories with multiple thresholds
Convert heritability between the observed and underlying scales
Fit a joint model for a categorical and a continuous trait

Assumes Ch 6, Ch 11.

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. Binary and ordered categorical traits in one chapter — same model, more thresholds.

---
title: "Threshold Models for Categorical Traits"
---

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

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

1. **Explain** the liability concept and the threshold model
2. **Set** up a threshold model for a binary trait and solve it iteratively
3. **Extend** to more than two ordered categories with multiple thresholds
4. **Convert** heritability between the observed and underlying scales
5. **Fit** a joint model for a categorical and a continuous trait
:::

*Assumes Ch 6, Ch 11.*

::: {.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.** Binary and ordered categorical traits in one chapter — same model, more thresholds.
:::