Advanced & Applied Topics · Item Response Theory (IRT)

Item response theory: Measurement fundamentals and limitations of classical test theory

Public introduction · full guide in Eikos

Introduction

What this guide covers

Introduction // Treatise on Psychometric and Statistical Methodology

Overview

Topics covered

  • Introduction
  • Fundamentals of Measurement and Item Response Theory
  • Fundamentals of Psychometric Measurement and Epistemology
  • Spearman's Linear Model ( ) and its Axioms
  • Axiom 1: Definition of True Score
  • Axiom 2: Null Correlation between True Scores and Errors

Related concepts

Main connections

  • Maximum likelihood estimation
  • Calculus & differentiation
  • Variance & standard deviation
  • Bayes' theorem & priors
  • Conditional probability & independence
  • Mathematical optimization & gradients

Compatible notation

Mathematical sample in LaTeX

The expression is rendered accessibly, with its LaTeX source preserved below.

Xj=Tj+Ej
View LaTeX sourceX_j = T_j + E_j