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An Investment Fund as a Function

From kwharrison13.com · Long read
An Investment Fund as a Function
AuthorFrank Long
PublishedNovember 9, 2026
FormatArticle
OriginalRead the original

A fund is a state machine that turns information into a (selection, size, timing) decision, and the job is to design the best graph of sub-functions to compute it, using agents only where they beat code, statistics or humans.

An Investment Fund as a Function

Key claims

  • The function: investment_fund(information) → decision, where information is news, filings, prices, data and risk limits, and the decision is one tuple: stock selection, size, time.
  • You can’t just ask a model. The problem has to be broken into sub-functions you can evaluate, like a series of lossy projections into lower-dimensional space.
  • Many valid decompositions: start from stocks and their KPIs and find the themes that move them, or start from themes and find the most exposed stocks.
  • And many ways to run each step: one agent per KPI vs. per stock; one reviewer vs. ten reviewers on different models with a majority vote, possibly weighted by model size and thinking time.
  • The graph keeps moving: the optimal shape shifts with each new model release.
  • Performance over AI usage: often deterministic code, statistical methods or humans are the best implementation of a step.

Notable replies

  • Sizing came up as the hardest part with noisy information; Long: “everything has been pretty darn hard.” Others questioned whether a static graph can handle non-stationary markets.

Connections

Curated by Kyle Harrison. Organized by Claude. Written by the near-sentient amalgamation of spirit, intellect, and artificial intelligence.