We study staged entry with costly gatekeeping in a differentiated-products economy: entrepreneurs observe noisy signals before paying a resource-intensive activation cost. Precision improves selection but requires real resources, reducing entry and variety: welfare need not rise with precision. Under CES preferences, the activation cutoff is efficient as profit displacement offsets the consumer-surplus gain from variety. Welfare losses arise from verification costs shrinking the feasible set of varieties, not from misaligned incentives. Because the market responds efficiently to any given regime, these losses cannot be corrected via Pigouvian taxes. [page::0]
This study analyzes how the 1923 Great Kanto Earthquake reshaped Tokyo's population distribution, using ward- and block-level census data and a monocentric framework to distinguish price-driven land-market adjustments from zoning policies. The reconstruction's land readjustment reduced residential land within burned areas, pushing up rents and delaying full population recovery; multi-story housing later offset some of the land-reduction effects, but population in burned wards remained below pre-quake levels through the mid-1930s. The pre-earthquake zoning system had little impact on post-disaster population shifts, indicating market-based price adjustments dominated. The analysis also shows rents rising with knock-on effects: kinship households declined while lodger housing rose as workers sought cheaper accommodations, implying housing sharing as an effective coping mechanism. Overall, the post-disaster population decline reflects the net of rent-driven losses and housing-sharing gains. [page::1]
We present a Kaplan-Meier and Cox proportional-hazards survival analysis of 832,941 Solana pump.fun token launches with 24-hour graduation outcomes observed between 2026-05-08 and 2026-06-10, yielding a pooled graduation rate of 0.198% (Wilson 95% CI [0.189%, 0.208%]) [page::0][page::3]. We formalise the Graduation Regime Windows (GRW) framework and designate the 34-day REDPUMP-2026-v1 regime, releasing the underlying 860,213-launch dataset under CC-BY-4.0 on Zenodo with a frozen schema [page::0][page::1]. Social-presence features are highly predictive: the Telegram indicator alone producing an 8.94× lift (HR 5.40, 95% CI [4.73, 6.17], p = 6.6 × 10−138) and launches advertising all three social channels yielding a 17.4× lift versus none [page::1][page::6]. The top quartile (mcap > 31 SOL) graduates at 0.634%, nearly matching the Marino et al. (2026) pooled rate, suggesting the cross-regime decline is largely due to compositional shifts toward zero-self-buy launches rather than a decline in self-buy success rates [page::7][page::8]. We introduce the GRW framework and Pump.fun Graduation Index (PGI) as standardized anchors for future work, and provide reproducible code and data access details [page::11][page::12].