Ian HelfrichPhDContact
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Ian Helfrich

Applied economist on the 2026–27 economics job market

Independent economist since 2024 · PhD in Economics, Georgia Tech, 2024

My job market paper, The rural mobilization gap in a U.S. place-based tax credit, finds that the rural private-leverage gap in the New Markets Tax Credit falls from −0.262 in the pooled comparison to −0.047 within the same Community Development Entity, where it is not statistically distinguishable from zero.

Job market paper (PDF)CV (PDF)Candidate page

I also tutor econometrics, statistics, Stata, Python, and SQL, and coach research design. Teaching and tutoring · Book an intro call

Ian Helfrich outdoors in a navy suit and patterned tie
Ian HelfrichSt. Louis, Missouri

Selected work

The full research record

Selected research and teaching

Rural–urban comparisonNMTC
Pooled and within-intermediary rural coefficientsPooled coefficient minus 0.262. Within-CDE coefficient minus 0.047; 95 percent confidence interval from minus 0.245 to plus 0.152. Descriptive comparisons, not causal effects. No pooled confidence interval is shown.-0.3-0.2-0.100.10.2Pooled comparison−0.262Within the same intermediary−0.047
Within-CDE bar: 95% confidence interval.
Descriptive comparisons; no causal effect is identified.

Job market paper · August 2026

The rural mobilization gap in a U.S. place-based tax credit

Does the rural private-leverage gap persist when rural and urban projects are compared within the same Community Development Entity?

I linked 19,907 transactions into 8,024 projects, documented their provenance, estimated pooled and within-CDE comparisons, and published the paper, code, viewer, and claim audit.

Ian Helfrich originated the project and is its sole author; Katia Antunes and Elizaveta Gonchar are acknowledged contributors.

Research record Working paper
Trade in the Spotlight
Bilateral distance
weighted by where
activity is located
PopulationNight lightsDistance

Preprint · SSRN 5202676 · 2025

Trade in the Spotlight

Does a gravity model fit better when bilateral distance reflects where population and measured economic activity are located within countries?

With Elizaveta Gonchar, I constructed annual bilateral distances from gridded population and VIIRS night-light intensity and evaluated them in gravity models of trade.

Coauthor with Elizaveta Gonchar

Research record SSRN preprint
Applied Statistics
QuestionEstimandEvidenceInterpretation
Two-group inference in JavaScript, Python, R, and Julia

Live public learning system · Version 0.1

Applied Statistics

How can a learner move from an estimand through computation, diagnostics, and a defensible interpretation in more than one statistical environment?

I built a browser-based workflow that connects those steps and verifies the same two-group analysis across JavaScript, Python, R, and Julia.

Designer, author, and developer

Project record Source repository

Also in the record: additional contributor to the semiconductor demonstration in Securing America's Future; ad hoc referee, Journal of Economic Theory. See the wider body of work.

How the site connects

Contours trace the softened potential of the site's pages, each weighted by its length and links; choosing a page sets the others in rings by link distance.

All 137 pages, by topic

International trade

Measurement

Place-based policy

Teaching

Profile and contact

What brings you here?

1,035+ platform-recorded Wyzant teaching hours as of August 2026. Teaching experience and source record.

Software & scientific visualization

Software and scientific visualization

Audio software and oceanographic mapping.

Live browser application

Yellowjacket

Transcript editing, signal analysis, and music production in one audio workbench.

Audio DSP · browser software · interaction design

Applied work & ongoing development

Oceanographic systems

3D seafloor mapping, ocean-current analysis, and scientific visualization.

Geospatial Python · 3D environments · model integration
Agulhas current map from depth-resolved HYCOM analysis

Interactive ocean atlas

Hidden Rivers

Model trajectories, rotation and stretching, with full-dimensional Tessera coastal search and a data-driven film.

HYCOM · NOAA ETOPO1 · Tessera
All projects
Interactive models

Economics in motion

Space / Structure / Uncertainty

Space, structure,
and uncertainty

Distance, distribution, and the shape of economic activity.

Work with space

Generative illustration.

Interactive modelsEconometrics experiments ↗

Models and calculations

Optimal transportMove mass between spatial distributions

Question

How does a mass distribution reallocate toward a new spatial target?

Choose the shape and location of a target distribution, then compute transport from the same fixed source.

Static source mass distributionA broad fixed source distribution awaits a user-selected target. The numerical definition, result, and limit are stated outside this figure.
The calculation begins only when Run transport is activated. Every run starts from the same fixed source; the visual motion follows the coupling's barycentric map.

The first number summarizes how far mass moves. The remaining figures separate movement of conditional means from residual spread and report solver accuracy.

Not run. Choose a target and activate Run transport.

Specialist diagnostics

Run transport to see the regularized W₂ approximation, iteration count, and marginal error.

The reported RMS includes both displacement of each conditional mean and the coupling's conditional variance. Source and target marginals must converge to the displayed numerical tolerance.

Regression sensitivityOutliers, leverage, and regression estimates

Question

How much can one observation change a fitted line and its uncertainty?

Add, move, or remove observations. The fitted line, confidence band, slope, robust standard error, and R² update together.

Editable least-squares scatterplotNine initial points on axes labeled Illustrative x and Illustrative outcome, with a fitted line and confidence band. Pointer users can add or drag points; equivalent add, remove, and reset buttons follow the figure.Illustrative xIllustrative outcome
The axes are illustrative. Pointer: select empty space to add a point, drag a point to move it, or select a point without dragging to remove it. Keyboard: use the controls below to add a tail point, remove the last point, or restore the fixture.

n=9 · fitted slope 3.33 per 10 horizontal units · robust slope SE (HC1) 0.22 · R² 0.94 · shaded area: conventional 95% confidence band for the fitted mean

Spatial allocationChange the metric, boundaries, and map
LAB 02 / SPATIAL ALLOCATION

A count becomes a map.
A map becomes a choice.

Place synthetic site locations inside synthetic planning districts, then change the metric, classification rule, and boundary decision. The map, legend, ranking, and export share one state.

DEMONSTRATION DATA / SYNTHETIC / 12 DISTRICTS / 93 SITES

ALLOCATION SURFACE / SYNTHETIC DISTRICTSRAW COUNT / NATURAL BREAKS
FOCUS A DISTRICT / USE ARROW KEYS
CLASS BREAKS2 to 33 to 55 to 88 to 1111 to 15
SELECTED DISTRICTR01 / NORTH FORK
Sites
8
Area
52 km²
Raw count
8
Map class
3 / 5
RANKED OUTPUT / ACTIVE STATE

The table remains inspectable.

Districts ranked by the active spatial metric
RankDistrictSitesArea km²Raw countClass
11563155
21384135
31148114
410140104
5913294
685283
777573
868963
9512152
10411042
11315531
1229721

Research topicsAll research ↗

Related projects

Lines connect projects with shared subjects or methods.

Topic map

Question

Which research records share explicit metadata tags?

Filter by metadata tag or maturity to see which projects share an explicit connection. Line weight shows how many tags they share.

Research records connected by shared metadata tagsThe complete records and connections are repeated in HTML tables after the figure.SpotlightTrade in the spotlight: enhancing gravity model predictions with nightlights and population-weighted distance measures (2025)Effective distanceEffective distance: a satellite-calibrated bilateral trade-cost panel, 2000-2024 (2026)UkraineOcclusion and adaptation: a closed-loop spatial-labor model of Ukraine's wartime economic reorganization, 2022-2025 (2026)DissertationRedefining Trade Dynamics: Incorporating Network Centrality, Spatial Heterogeneity, and Optimal Transport Theory into Models of International Trade (2024)OT equilibriumA unifying framework for economic equilibrium and optimal transport in infinite-dimensional Hilbert spaces (2024)AI validityHuman or Machine? Out-of-Time Validation of Task-Level AI Exposure Ratings (2026)NMTCThe rural mobilization gap in a U.S. place-based tax credit (2026)PenumbraPenumbra: closed-loop observation under measurement gaps in cross-border trade (2026)Russian crudeEmpirical observation equilibria: the Russian seaborne-crude corridor, 2021-2024 (2026)AI × laborAI and the Entry-Level Labor Market (2026)
Filter by tag or maturity, or drag a record to explore its connections. The tables below provide the same records, tags, connections, and links in text.

10 records; 14 shared-tag connections.

Research records and tag-derived connections
Research records in the graph
RecordYearMaturityStatusMetadata tags
Trade in the spotlight: enhancing gravity model predictions with nightlights and population-weighted distance measures2025circulatingpreprinttrade, gravity, nightlights, effective-distance, geospatial
Effective distance: a satellite-calibrated bilateral trade-cost panel, 2000-20242026developmentdrafttrade, gravity, effective-distance, satellite-economics, panel-data
Occlusion and adaptation: a closed-loop spatial-labor model of Ukraine's wartime economic reorganization, 2022-20252026developmentdraftukraine, wartime-economy, spatial-labor, satellite-economics, sanctions
Redefining Trade Dynamics: Incorporating Network Centrality, Spatial Heterogeneity, and Optimal Transport Theory into Models of International Trade2024earlierpublishedinternational-trade, networks, gravity, spatial-economics, optimal-transport
A unifying framework for economic equilibrium and optimal transport in infinite-dimensional Hilbert spaces2024circulatingworking paperoptimal-transport, equilibrium-theory, infinite-dimensional, Hilbert-spaces
Human or Machine? Out-of-Time Validation of Task-Level AI Exposure Ratings2026developmentdraftlabor, artificial-intelligence, measurement, validation, occupations
The rural mobilization gap in a U.S. place-based tax credit2026circulatingworking papernmtc, blended-finance, rural, intermediary-FE
Penumbra: closed-loop observation under measurement gaps in cross-border trade2026developmentdraftsanctions, satellite-economics, optimal-transport, measurement, shadow-trade
Empirical observation equilibria: the Russian seaborne-crude corridor, 2021-20242026developmentdraftsanctions, russian-crude, AIS, satellite-economics, empirical-OT
AI and the Entry-Level Labor Market2026developmentworking paperlabor, artificial-intelligence, event-study, cps, early-career
Connections derived from shared tags
First recordSecond recordShared tagsWeight
Trade in the spotlight: enhancing gravity model predictions with nightlights and population-weighted distance measuresEffective distance: a satellite-calibrated bilateral trade-cost panel, 2000-2024trade, gravity, effective-distance3
Trade in the spotlight: enhancing gravity model predictions with nightlights and population-weighted distance measuresRedefining Trade Dynamics: Incorporating Network Centrality, Spatial Heterogeneity, and Optimal Transport Theory into Models of International Tradegravity1
Effective distance: a satellite-calibrated bilateral trade-cost panel, 2000-2024Occlusion and adaptation: a closed-loop spatial-labor model of Ukraine's wartime economic reorganization, 2022-2025satellite-economics1
Effective distance: a satellite-calibrated bilateral trade-cost panel, 2000-2024Redefining Trade Dynamics: Incorporating Network Centrality, Spatial Heterogeneity, and Optimal Transport Theory into Models of International Tradegravity1
Effective distance: a satellite-calibrated bilateral trade-cost panel, 2000-2024Penumbra: closed-loop observation under measurement gaps in cross-border tradesatellite-economics1
Effective distance: a satellite-calibrated bilateral trade-cost panel, 2000-2024Empirical observation equilibria: the Russian seaborne-crude corridor, 2021-2024satellite-economics1
Occlusion and adaptation: a closed-loop spatial-labor model of Ukraine's wartime economic reorganization, 2022-2025Penumbra: closed-loop observation under measurement gaps in cross-border tradesatellite-economics, sanctions2
Occlusion and adaptation: a closed-loop spatial-labor model of Ukraine's wartime economic reorganization, 2022-2025Empirical observation equilibria: the Russian seaborne-crude corridor, 2021-2024satellite-economics, sanctions2
Redefining Trade Dynamics: Incorporating Network Centrality, Spatial Heterogeneity, and Optimal Transport Theory into Models of International TradeA unifying framework for economic equilibrium and optimal transport in infinite-dimensional Hilbert spacesoptimal-transport1
Redefining Trade Dynamics: Incorporating Network Centrality, Spatial Heterogeneity, and Optimal Transport Theory into Models of International TradePenumbra: closed-loop observation under measurement gaps in cross-border tradeoptimal-transport1
A unifying framework for economic equilibrium and optimal transport in infinite-dimensional Hilbert spacesPenumbra: closed-loop observation under measurement gaps in cross-border tradeoptimal-transport1
Human or Machine? Out-of-Time Validation of Task-Level AI Exposure RatingsPenumbra: closed-loop observation under measurement gaps in cross-border trademeasurement1
Human or Machine? Out-of-Time Validation of Task-Level AI Exposure RatingsAI and the Entry-Level Labor Marketlabor, artificial-intelligence2
Penumbra: closed-loop observation under measurement gaps in cross-border tradeEmpirical observation equilibria: the Russian seaborne-crude corridor, 2021-2024sanctions, satellite-economics2

Contact

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