California

12 articles

Better Access, Higher Vulnerability: 9,033 CA Tracts

Across 9,033 California census tracts, better grocery access often coincides with higher food-security vulnerability, complicating the food-desert framework.'s food desert framework assumes that distance to grocery stores is a primary barrier to food access.

Dec 2025 · Food Security

Renters vs. Owners: Housing Tenure and Grocery Access

Renter-dominated tracts have better grocery access: shorter distances (0.58 vs. 0.94 mi), lower food desert rates (8.4% vs. 18.2%).

Dec 2025 · Transit Equity

Who Gets Left Behind: Transit Access and Race in California

Majority-minority tracts have shorter distances to grocery stores (0.72 vs. 0.85 miles) but higher mobility desert rates (13.2% vs. 11.1%).

Dec 2025 · Transit Equity

Scaling Up: From 7 Counties to Statewide

Expanding from 2,000 to 9,039 census tracts reveals what scales linearly (Census API, KD-trees) and what requires adaptation (transit aggregation, memory…

Dec 2025 · Methodology

Building a Better Metric: The Residualized Accessibility Index

Income, density, and car ownership explain 81% of county-level food-security vulnerability; residualization separates the structural signal from the rest.

Nov 2025 · Methodology

Why County Rankings Confound Policy with Context

Merced County's vulnerability index is 2.3 times higher than San Francisco's. But before drawing policy conclusions, we need to understand what that number…

Nov 2025 · Methodology

Mobility Deserts: Close on Paper, Unreachable by Car

Federal food access policy assumes proximity equals access. But in California, 1 in 8 neighborhoods face a hidden barrier: stores are within a mile, but poor…

Nov 2025 · Transit Equity

The Widening Gap: Why Some Neighborhoods Are Falling Behind

County-wide SNAP rates rose 2 points over four years. But what happens when we look at neighborhoods instead of the whole county?

Oct 2025 · Food Security

The Food Security Gap: How COVID Widened Inequality

County-wide SNAP participation stayed flat during the pandemic. But a census tract analysis of 408 neighborhoods reveals what aggregate data hides: food…

Oct 2025 · Food Security

The Retail Density Paradox: Why More Stores Mean Worse Data

A verification method for EBT acceptance across the roughly 28,800 California stores in the USDA list, where more retailers means messier, not better, data.

Oct 2025 · Methodology

When Work Isn't Enough: Silicon Valley's Working Poor

In 57 census tracts across Santa Clara County, more than 60% of working-age adults are employed. These same tracts have poverty rates above 10%.

Oct 2025 · Food Security

How Neighborhood Intersections Predict Food Insecurity

A validated neighborhood food-security index showing why single demographic factors miss the mark, and how intersecting conditions predict vulnerability better.'t tell the full story.

Sep 2025 · Food Security