This book defines the observable object, the counterfactual target, and the information a representation must preserve. It connects exact identification, local repair, approximate loss, measurement across environments, timing error, administrative transmission, and model comparison through one target-directed language.
This book connects population arguments to sampling evidence. It covers conditioning, randomized contrasts, partial identification, competing rates, extremum estimators, simulation error, generated objects, spectral uncertainty, dependent-data covariance, bootstrap frontiers, and out-of-time validation.
This book develops the mathematical tools needed to differentiate equilibrium systems, trace policy paths, analyze dynamic responses, work with inverse problems, and certify optimization claims. Each tool is tied to an economic question and accompanied by a diagnostic that separates a valid calculation from a stronger conclusion.
This book carries economic primitives through choice, equilibrium, measurement, and welfare calculations. It emphasizes executable model contracts: every counterfactual uses the same utility, state, transition, choice set, normalization, and shock law unless a stated alternative model changes one of those objects.
This book presents a reproducible method for checking the chain from assumptions to claims, proofs, computations, and public artifacts. Six self-contained case studies show how the method works across selection, simulation, dynamics, demand, set-valued choice, and inverse problems.