GISValTech2025

Welcome to the 26th Annual GIS/Valuation Technologies Conference. Hear from Rob McGee, 2025 Conference Chair, about the not-too-miss education and valuable networking on the agenda.

Leaders from both the International Association of Assessing Officers and the Geospatial Professional Network (formerly known as URISA) will also be on hand to update attendees about organizational initiatives and opportunities to contribute.

Then look forward to an impactful keynote address!
Rebuilding Public Trust: The Need for Strong Information Ecosystems
Where can I see my neighbor’s new assessed value?” This is a question about the property valuation process Signal Cleveland received in our coverage of the process for Cleveland and Cuyahoga County. As people with experience with property data and the tax valuation process, you know one single neighboring value is unlikely to provide much helpful information.

But the land and its use is the lifeblood of a community; having high-quality information about it is vital to its health, and people want access to this information and transparency around public processes like property valuation. In this session, we’ll look at what makes up a healthy community information ecosystem, including the role of community input and local media. Then, we’ll walk through how accessible data on properties can be used to understand important critical components of the housing market. Finally, we’ll take a look at questions/implications for community data stewardship and governance.

Enjoy a hosted buffet luncheon and quality time with your fellow conference attendees. Dessert will follow in the exhibit hall (which opens after lunch).

Sponsored by Assessment Analyst® GAMA by Esri Canada

A case study of GIS use in the 2023 countywide reappraisal conducted by the Franklin County Auditor’s office. The Auditor and GIS Director will share approaches to determine values, prepare constituents, and track the impacts of historic value increases while striving to incorporate best practices for appraisal, minimizing bias, and incorporating new technologies.

New software was utilized by appraisers to collect data for sketch validation and parcel descriptions. A GIS application helped appraisers reconfigure neighborhood delineations and visualize property characteristics easily. A new website, “Know your Home Value” was introduced that allowed constituents to compare their home values with their neighbors and included a tax estimator. This work continued to track the appellate process and address concerns and questions resulting from the value and related tax changes.

Constituent engagement was focused on accessibility and transparency. In 9 months leading up to the release of the proposed values, over 100 community presentations shared GIS maps, delineated neighborhoods, and sales review comparisons to prepare the constituents for the forecasted value increases while a targeted public relations campaign addressed the factors that went into this “perfect storm”.

Mass appraisal plays a crucial role in efficiently and equitably valuing large numbers of properties, but achieving fairness and accuracy remains a challenge. While traditional models like linear regression have been commonly used, machine learning has proven to be effective, offering several benefits and strengths. To better understand these methods, the IAAO AI Taskforce has been tasked with researching and comparing various AI methodologies. In this panel, we will take an international perspective, comparing datasets from multiple countries to explore how these AI models—such as Decision Trees, Random Forest, Gradient Boosting, and Neural Networks—can be adapted to different valuation environments. By examining case studies across diverse regions, we aim to highlight best practices in using AI to create accurate and equitable property values worldwide.

IAAO AI Task Force
Luc Hermans, Data Scientist, Netherlands Council for Real Estate Assessment*
Russ Thimgan, President, Thimgan & Associates, Inc.*
Daniel Fasteen, Ph.D., Senior Research Scientist, Tyler Technologies*
Luke Jorgensen, Data Scientist, Lee County Property Appraiser’s Office*
Joshua Jorgensen, Data Scientist, Lee County Property Appraiser’s Office*
Paul Bidanset, Ph.D., Founder, Center for Appraisal Research and Technology*
Joe Wehrli, Enterprise Architecture Manager, Tyler Technologies*
Michael McCord, Ph.D., Ulster University 
Pim Hessing, Data Analyst, Netherlands Council for Real Estate Assessment
John Valente, Appraisal Regional Manager, Tyler Technologies
Anita Ng, Assistant Commissioner (Corporate and Technology) Services, the Government of Hong Kong Special Administrative Region, China
 
*In attendance