Implied volatility surface

Model SenseIntelligence & Judgment

Models are math.
Risk is human.

Model Sense connects ALM modeling knowledge to practical use: a practitioner book, an interactive modeling lab, and a deposit-modeling masterclass for the bank treasury and risk teams who build, validate, and defend these models.

01About

Chih Chen

Creator, Model Sense · ALM modeling practitioner

LinkedIn profile
CFA FRM CMA BTRM
Models are tools, not oracles. They can be useful without being precise or accurate all the time.

Built on one premise.

Model Sense exists on a single premise: that models are tools, not oracles. They can be useful without being precise or accurate all the time, and knowing the difference between a model that is useful and one that is merely elaborate is the central discipline of responsible ALM practice.

The practice was founded to fill a gap in how ALM modeling knowledge is transmitted. The textbook treatments are either too theoretical for practitioners or too product-specific to be portable. The practitioner who built something useful rarely has time to explain it at length, and the explanation is usually compressed into a conference slide. Model Sense is an attempt to slow that down: to take the behavioral models that actually drive bank balance sheet risk, work through the mechanics honestly, and teach them in a way that transfers across institutions, regulators, and rate environments.

The vehicles are a forthcoming book with Palgrave Macmillan, hands-on training for practitioners who need to build or defend these models, and a browser-based ALM Model Lab that makes the mechanics visible without a vendor black box. The thread across all of them is the same: intellectual honesty, fit-for-purpose thinking, and the practitioner's obligation to know what a model cannot do.

02The Book

Practical ALM
Behavioral Modeling

How Deposit Behavior, Interest Rate Risk, and Liquidity Shape Bank Balance Sheets

Under contract with Palgrave Macmillan, with the manuscript due in January 2027. The book teaches the principles of ALM modeling and how behavioral models connect to the measurements they feed: gap, funds transfer pricing, replicating portfolios, EVE, NII, and survival horizon.

The organizing thesis is George Box: all models are wrong, but some are useful. Every chapter approaches its model class from a risk-aware perspective, pairing the conceptual framework with hands-on mechanics. A single running example, a digital bank named AI First Bank, carries the reader from first principles through model governance. The recurring anchor is the 2023 bank failures, where deposit behavior and interest rate risk converged in a way that made transparent, fit-for-purpose models matter more than elegant ones.

Publisher
Palgrave Macmillan, under contract
Manuscript
Due January 2027
Running example
AI First Bank, from first principles to model governance
Written for
ALM analysts, treasury, and risk teams
Join the waitlist

Chih Chen

Practical ALM Behavioral Modeling

How Deposit Behavior, Interest Rate Risk, and Liquidity Shape Bank Balance Sheets

palgrave
macmillan

Yield curves through time

Wireframe yield curve surface drawn in ink on paper

03Interactive

ALM Model Lab

A browser-based modeling lab. It bootstraps the SOFR curve, fits SABR to the cap-vol surface, calibrates Hull-White and BGM/LMM rate models, runs Monte Carlo simulation, and drives calibrated deposit, CD, and mortgage behavioral models through the ALM analytics that connect rates to the balance sheet. No install, no vendor black box; the assumptions are explicit and the mechanics are visible.

Wireframe implied volatility surface drawn in ink on paper, rising at both strike wings above a contour floor

SABR implied volatility surface

01

Rate models

Bootstrap the SOFR curve. Fit SABR to the cap-vol smile; calibrate Hull-White 1F and BGM/LMM to cap and swaption surfaces. Simulate forward paths with Monte Carlo.

02

Behavioral models

A calibrated behavioral suite: competing-risks mortgage prepayment and default, demand-deposit and money-market decay, and CD early redemption. Each model switches between its calibrated form and a classroom form, so the mechanics stay visible.

03

ALM analytics

Repricing gap, liquidity gap, funds transfer pricing, stochastic replicating-portfolio optimization, and the Sensitivity-Equivalent Gap that bridges behavior to risk measures.

04

Instruments

Fixed and floating loans, mortgages, demand and money-market deposit books, a CD book, and the cash-flow engine they share across every analytic.

→On the roadmap

AI First Bank mini-ALM engine

The book's running balance sheet, modeled end to end inside the Lab.

Balance-sheet optimization

A portfolio optimizer connecting balance sheet composition to repricing gap, NII sensitivity, and EVE targets.

Open the Lab and run a model.

Calibrate to the bundled quarter-end market snapshot, simulate a rate path, and watch a deposit book decay against it. Built as the book's companion playground.

Launch the Lab Best on desktop. For educational use only.

04Live training

Deposit Modeling
for Bank ALM

A focused program on building deposit behavioral models that hold up in practice: non-maturity deposit decay, dynamic rate-sensitive betas, the separation of surge from core, and the link from deposit behavior to net interest income and economic value of equity. Built for treasury and risk professionals who need models they can defend to an examiner and to an ALCO.

Format
Live virtual training
Date
Forthcoming
Written for
Treasury and risk teams
Register your interest

→What it covers

  • Non-maturity deposit decay and component-based attrition
  • Dynamic, rate-sensitive deposit betas (the S-curve)
  • Surge versus core, and the false-precision trap
  • From deposit behavior to NII and EVE
  • Model validation and what an examiner looks for

Deposit survival by account age

Wireframe deposit survival surface: share of accounts remaining falls steeply with account age then flattens, one row per rate regime

05Research & writing

Published work

Selected research on deposit behavior, interest rate risk, and the bridge from repricing gaps to risk measures.

SSRN Working Paper · August 2026

Developing an account-level mortgage prepayment model with an agentic AI team

Methodology, calibration, and the case for human validation: a competing-risks prepayment and default model built on public Freddie Mac loan-level data.
Read
SSRN Working Paper · 2026

Dynamic Deposit Betas: An Asymmetric Volatility-Adjusted S-Curve Framework for MMDA Rate Sensitivity

An asymmetric S-curve model for estimating MMDA deposit betas, incorporating volatility adjustment to capture rate-environment-dependent pass-through dynamics.
Read
SSRN Working Paper · 2025

Beyond Static Bifurcation: A Regime-Aware Approach to Nonmaturity Deposit Modeling

A regime-conditional framework for nonmaturity deposit modeling that moves beyond fixed core/transactional splits toward rate-environment-aware segmentation.
Read
Journal of Risk Management in Financial Institutions · 2025

Dynamic Deposit Behaviours in IRRBB: Enhancing Risk Management through Sensitivity Analysis

Examines how deposit behavioral assumptions propagate into IRRBB sensitivity metrics and quantifies the effect on EVE and NII risk measures.
Read
BTRM Working Paper Series #23 · 2025

A Component-Based Model for Non-Maturity Deposit Decay Incorporating Interest Rate and Credit Spread Sensitivity

Decomposes NMD decay into interest rate and credit spread components, enabling more granular behavioral modeling of deposit runoff under stress.
Read
BTRM Working Paper Series #20 · 2024

The Impact of Deposit Modeling on Interest Rate Risk in the Banking Book (IRRBB) Sensitivity Metrics: A Worked Illustration

A worked illustration of how deposit modeling choices flow through to EVE and NII sensitivity outputs under standard IRRBB shock scenarios.
Read

06Get in touch

Let's talk models.

For the book waitlist, masterclass registration, or a question about the ALM Model Lab, send a note.

Email Model Sense