Deep Work: Rules for Focused Success in a Distracted World · chapter 3 · id deep-work-c3-08-the-pareto80-20-principle-appl
“The Pareto/80-20 principle applies to professional tool selection: roughly 20% of your tools produce 80% of your results. Newport recommends the 'craftsman approach' of selecting only tools that substantially support vital activities.”
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Pareto Principle -- Wikipediasource alive
Empirically supported in software (IBM bugs), healthcare spending, B2B sales. Based on power law distributions. The 80/20 ratio is approximate, not exact.
Gabaix, X. (2009) - Power Laws in Economics and Finance, Annual Review of EconomicsDOI registry: valid
Power law distributions (including the Pareto principle) appear across economic outcomes including firm sizes, income, and productivity. The 80-20 rule is an empirical regularity, not a mathematical law, and the exact ratio varies by domain.
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