Permutation and placebo tests

The Economic Geography of Digital Retail Supply: Product Diversity, Regional Specialization, and the Hidden Structure of Quebec's Online Economy

Evidence from 390,108 product listings of 1,569 Quebec online stores across 17 administrative regions (Fabri-Ka snapshot, 1 November 2026)

Simon-Pierre Boucher · UQO Working Papers · November 2026 · v1.0

Can product-level online catalogues reveal the spatial organisation, diversity and specialization of a regional retail economy beyond what business counts show? This paper studies one read-only snapshot (1 November 2026) of Fabri-Ka, an aggregator of the public catalogues of 1,569 Quebec-based online stores (390,108…

The Hidden Architecture of Grocery Prices: Promotions, Retail Competition, and the Cost of Living in Quebec

Evidence from 300,613 posted-price events across 54 Quebec grocery feeds, August–November 2026

Simon-Pierre Boucher · UQO Working Papers · November 2026 · v1.0

Grocery prices are not a single inflation process. Using a read-only research copy of Food-Ka, a Quebec grocery price aggregator, the paper assembles an auditable panel of 124,579 listings from 54 active source feeds (26 retail companies, two channels: online storefronts and weekly circulars) observed every seven…

The Hidden Dynamics of Used-Car Markets: Price Discovery, Inventory Liquidity, and Strategic Dealer Behavior

Evidence from a Daily Panel of 273,265 Quebec Listings

Simon-Pierre Boucher · UQO Working Papers · November 2026 · v1.0

The paper studies price discovery and liquidity in the Quebec used-car market with a daily panel of 273,265 dealer listings observed by the aggregator Auto-Ka between 12 August and 1 November 2026, with every asking-price change and listing disappearance recorded about seven times a day. Hedonic models with flexible…

Faster, Wider, More Fragile? The Evolution of Intraday Shock Propagation in U.S. Equity Markets, 1992–2026

Simon-Pierre Boucher · UQO Working Papers · October 2026 · v1.1

This paper studies how intraday shocks travel across U.S. equities using 7.69 billion one-minute bars covering the full listed and delisted cross-section from 1992 to 2026. Three findings emerge. First, isolated idiosyncratic shocks barely spread: across 1.85 million ±6σ one-minute events, the abnormal share of other…