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Δln⁡TFP≈∑s∈Aαs⋅πs\Delta \ln \text{TFP} \approx \sum_{s \in \mathcal{A}} \alpha_s \cdot \pi_s

Why this formula appears here

where each task y(s) can be performed by labor or by an automated system if that task falls within the feasible automated set A\mathcal{A} . Under Hulten’s theorem, the first-order aggregate TFP cost savings from automating a subset of tasks is bounded by the expenditure share of the automated tasks multiplied by the average unit cost reduction: Δln⁡TFP≈∑s∈Aαs⋅πs\Delta \ln \text{TFP} \approx \sum_{s \in \mathcal{A}} \alpha_s \cdot \pi_s. where αs\alpha_s is the baseline economic share of task s and πs\pi_s = cL(s)−cA(s)cL(s)\frac{c_L(s) - c_A(s)}{c_L(s)} represents the proportional cost reduction achieved on that task [ 2 ] .

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Δ\Delta

Symbol Δ

Δ is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

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ss

Symbol s

s appears in the bound of this sum. The bound states where the repeated operation starts, ends, or which values it includes.

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A\mathcal{A}

Symbol A

A appears in the bound of this sum. The bound states where the repeated operation starts, ends, or which values it includes.

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αs\alpha_s

Symbol alpha_s

alphasa_s is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

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πs\pi_s

Symbol pi_s

pisi_s is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

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s∈As \in \mathcal{A}

Starting index or lower bound: s in A

This label says where the repeated addition, multiplication, or accumulation starts. Read its value or condition together with the article’s description of the index.

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Published contexts (1)

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Δln⁡TFP≈∑s∈Aαs⋅πs,\Delta \ln \text{TFP} \approx \sum_{s \in \mathcal{A}} \alpha_s \cdot \pi_s,

Equation 10 · AI Economics & Systems

The Jagged Frontier Fallacy: Deconstructing Harvard's Canonical AI Productivity Study

This equation gives an approximation: it relates the quantities while allowing an approximation.

where each task y(s) can be performed by labor or by an automated system if that task falls within the feasible automated set A\mathcal{A} . Under Hulten’s theorem, the first-order aggregate TFP cost savings from automating a subset of tasks is bounded by the expenditure share of the automated tasks multiplied by the average unit cost reduction: Δln⁡TFP≈∑s∈Aαs⋅πs\Delta \ln \text{TFP} \approx \sum_{s \in \mathcal{A}} \alpha_s \cdot \pi_s. where αs\alpha_s is the baseline economic share of task s and πs\pi_s = cL(s)−cA(s)cL(s)\frac{c_L(s) - c_A(s)}{c_L(s)} represents the proportional cost reduction achieved on that task [ 2 ] .

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