DISTRIBUTIONSSTARTER
Power Law / Long Tail
Rich-get-richer: a few huge winners, many tiny players. Straight line on log-log.
How it works
- Growth plus preference for the already-big compounds into extremes.
- On log-log axes the curve straightens — slope is the exponent.
- The mean misleads: most sit below it, a few tower above.
Use → City sizes, book sales, network degrees. Never average it like a normal.
Watch out → Averaging power-law data invents a 'typical' case that barely exists.
Try it → Rank site traffic or sales by size and plot rank vs size on log-log.
REDCAPE jobs → Explain · Predict
Free sources → SFI Fractals & Scaling • Wikipedia: Power law (CC BY-SA)
Attach to a lattice — combines with
Different families, shared jobs. Disagreement between them is where insight lives.
GROWTH
Exponential & Solow Growth
Compounding plus capital, labor and ideas explain why some economies stall.
SHARED JOBS: EXPLAIN · PREDICT
SORTING & PEER EFFECTSGranovetter Threshold
Each person has a join threshold; cascades depend on the distribution, not the average.
SHARED JOBS: EXPLAIN · PREDICT
NETWORKSPercolation / Tipping Points
Sparse links suddenly gel into a giant component — bank networks and blackouts tip fast.
SHARED JOBS: EXPLAIN · PREDICT
More in Distributions
Normal Distribution
Bell-curve averaging: many small independent effects sum to a predictable center with thin tails.
Central Limit & Six Sigma
Sample averages settle to normal; variation reduction pays until returns diminish.
Poisson Arrivals
Counts of rare independent events per window: calls, mutations, clicks.