The S-Curve

Welcome to The S-Curve

Now you will be able to receive the latest announcements, product updates, and our insights on the mortgage market in real time.

The name of the blog, the S-Curve, is a reflection of our logo and the central feature of our prepayment model. S-curves are seen in nature in many phenomenon, from population growth to prepayment and default models. Our first S-curve, in the early 1990s, used the arctangent function, then piece-wise linear functions, and evolved over time to be more complex and vary by FICO, loan size and LTV. This evolution encapsulates both the timeless nature of fundamental relationships and constant innovation to describe them better over time.

We hope you find the information useful and we look forward to your feedback.

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Blog - Latest
  • Introducing a New Interface to Navigate Our Website with Ease

    AD&Co Marketing Team

    News

    We proudly launched our new website on November 13th. As you familiarize yourself with the new look of ad-co.com, you will come to know the many new offerings we provide. Along with the new website, we have organized our products as a menu of models and applications for a wide range of investor appetites. Let us review the menu of our product offerings.

    Dynamic Models

    LoanDynamics (LDM) is the credit modeling solution you need. Our behavioral model helps you manage interest rate and credit risks in single family, multifamily, and auto loans by forecasting prepayments, delinquencies, defaults, and loss probabilities.

    RiskValDynamics (RVD) is our flexible valuation engine formerly known as OAS Subroutines. It combines LDM, our suite of MacroDynamics models, and our original, highly-efficient cash-flow engines.  

    MacroDynamics (MDM) is our suite of macroeconomic models including InterestRateDynamics, HomePriceDynamics, and UnemploymentDynamics.

    Applications 

    Kinetics is our new modular platform, designed to deliver the full suite of our models and analytics with the option to license only the tools you need. LoanKinetics , our multi-functional whole loan application, joins the Kinetics platform, along with MSRKinetics (MSRK), our new web-based offering focused on assessing MSR risk, and PoolKinetics, a module for pay-up valuation of agency pools.

    RiskProfiler (RP) is our complete valuation and risk assessment solution that covers all asset classes modeled by AD&Co: MBS and ARM pools, loans and their derivatives (IO, PO, MI, MSR), structured securities (CMOs), and hedge instruments. All inputs and outputs are stored in a SQL database.

    We hope the new interface helps you learn more about all that Andrew Davidson & Co., Inc. can offer during these unprecedented times.

    Happy Holidays and Stay Safe – Ashlea Bonds, Marketing

    ashlea@ad-co.com
    212-274-9075

     

     

  • Andrew Davidson & Co., Inc.’s LoanDynamics Models Empowers Fite Analytics’ MBS Analytics Service

    AD&Co Marketing Team

    News

    Andrew Davidson & Co., Inc. (AD&Co), is proud to support Fite Analytics’ innovative cloud-native Mortgage-Backed Securities Analytics Service. The Fite Analytics solution incorporates AD&Co’s LoanDynamics models that provide forecasts of voluntary prepayments, defaults and losses that drive risk analytics across the mortgage-backed securities market with comprehensive coverage. To read the full press release click here.

     

  • Introducing the New AD&Co Website

    Eric Limjoco

    News

    We are thrilled to announce that Andrew Davidson & Co., Inc. has launched a new look for ad-co.com. Some of the exciting new features of this site include:

    • A dynamic homepage highlighting the firm’s latest innovations, AD&Co client benefits, announcements, and Diversity, Equity and Inclusion efforts.

    • Our new blog titled The S-Curve that offers our latest announcements, product updates, and insights on the mortgage market in real time.

    • An enhanced solutions-focused structure organized by I Work In (includes industry and investment categories), Tools (product pages), Consulting, Insights (announcements and literature), and Client Portal (downloads portal and model resources). 

    • About AD&Co includes Our Company and Diversity, Equity, and Inclusion sections which offer a look into the firm’s foundation, culture, and practices.

    Please take the time to:

    Finally, we’ve updated our Terms of Use and Privacy Statement. You will be asked to accept them when you log in for the first time.

    Please let us know feedback or concerns to ensure we continue to serve you well. Thank you.

Blog - Archives

The S-Curve Archives

  • Ashlea Bonds

    News

    We’re excited to announce a major addition to the Andrew Davidson & Co., Inc. (AD&Co) team. Industry leaders Kelli Sayres and Gene Park, known for building and scaling leading fixed-income analytics platforms, have joined AD&Co’s Business Development team.

  • Sanjeeban Chatterjee, Vivian Li, Joni Baker, Richard Cooperstein

    Thoughts

    Building on our earlier research on expanded consumer attributes, AD&Co continues to explore how credit data contributes to modeling delinquency and prepayment risk, which are key drivers of mortgage servicing rights cash flows and valuation.

  • Joann Gollette

    Events

    Andrew Davidson recently joined NFM Lending’s Greg Sher on the One On One podcast to discuss our recent white paper, “The Impact of Moving Away From the Tri-Merge Standard.”

  • Eknath Belbase, Daniel Swanson, Yvonne Chen

    Events

    AD&Co recently sponsored and attended SFVegas 2026 and Optimal Blue Summit 2026. This post shares the AD&Co team's unique perspectives and key takeaways from attending both conferences.

  • Alex Levin

    News

    AD&Co US Mortgage High Yield Indices

    The Federal Reserve Economic Data (FRED) portal, housed by the Federal Reserve Bank of St. Louis, has been publishing AD&Co’s CRT indices since 2019. These series posted under the overall name of “US Mortgage High-Yield” include total return rates and credit and option-adjusted spreads (crOAS) – a projected return’s spread over Treasury (in the past, Libor). These series are available going back to 2014-end and tiered by CRT initial supports.

  • Joni Baker, Sanjeeban Chatterjee, Richard Cooperstein, Andrew Davidson

    Thoughts

    In July 2025, the US Federal Housing Finance Agency (FHFA) announced that the government-sponsored entities (the Enterprises or GSEs), Fannie Mae and Freddie Mac, would permit lenders to choose between Classic FICO and VantageScore 4.0 credit score models for loans sold to the GSEs. FHFA also stated in a social media post that the tri-merge standard would be maintained for mortgage underwriting. Nevertheless, some mortgage industry stakeholders recommend moving away from the tri-merge standard for GSE mortgages in favor of a single or bi-merge report standard.

  • Joann Gollette

    News

    As housing faces more climate threats that result in more losses, the insurance program that it sits on is teetering on the brink of collapse. Yet, the home insurance market has three distinct stakeholders that have competing priorities, and today, there is no motivation for a collaborative solution.

    Understanding how to strengthen and protect the current structure requires looking at the cost burdens along with the risk for each of those parties.

  • Sanjeeban Chatterjee

    Thoughts

    There has been a flurry of activity in the mortgage markets since the 2018 passage of the Economic Growth, Regulatory Relief, and Consumer Protection Act. This act requires the Federal Housing Finance Agency (FHFA, now known as US Federal Housing) to validate and modernize the credit score models used in the housing finance system. It should be noted that so far, the discourse has been around mortgages sold to the Enterprises (Fannie Mae and Freddie Mac). Ginnie Mae has not provided any guidance on their plans to start using new credit score models.

  • Vivian Li, Rob Landauer

    Events

    Andrew Davidson & Co., Inc (AD&Co) proudly sponsored IMN’s 11th Annual Mortgage Servicing Rights (MSR) Forum by Informa at the New York Hilton Midtown. Senior modeler Daniel Swanson joined the “Managing Delinquencies & Forbearance Value” panel in discussing how servicers are adapting to today’s market and the evolving delinquency trends.

  • Kevin Lin, Eknath Belbase

    Podcast

    Tune in to our fourth episode of AD&Conversations with Kevin Lin and Eknath Belbase, our product lead for our Climate model. In this episode, they discuss the new Climate Impact Suite (CIS) pilot project, and Belbase outlines several challenges the team is navigating, including: