Related research interest

Luis A. N. AmaralDept. Chemical and Biological

EngineeringNorthwestern Institute on Complex

Systems

Indiana University Workshop

May 21st, 2006

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High-throughput approach

Metabolism

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“Systems” approach

“A protein interaction map of Drosophila melanogaster”

Giot et al (2003)

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The power of cartography

http://maps.google.com

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Information but no understanding

Vesconte Maggiolo, Portolan Chart (1512)

Too much information

Lack of conventions: Oriented with North on bottom

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The metabolic network of E. coli

Guimera & Amaral, Nature 433, 895 (2005)

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A cartographic representation

Guimera & Amaral, Nature 433, 895 (2005)

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A cartographic representation

Guimera & Amaral, Nature 433, 895 (2005)

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The “invisible college”

Diversity

Exp

ertis

e

Guimera, Uzzi, Spiro & Amaral,Science 308, 697 (2005)

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Different assembly mechanisms yield different collaboration networks

Collaboration network of Econometrica authors

Collaboration network of Astronomical Journal authors

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Most fields live close to the edge

Guimera, Uzzi, Spiro & Amaral,Science 308, 697 (2005)

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Fraction of incumbents predicts quality of output

Impact factor - a (bad) proxy for journal quality

Guimera, Uzzi, Spiro & Amaral,Science 308, 697 (2005)

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Propensity to establish new collaborations with other incumbents predicts quality of output

Impact factor - a (bad) proxy for journal quality

Guimera, Uzzi, Spiro & Amaral,Science 308, 697 (2005)

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Density classificationSystem with N unitsEach unit connects to k neighborsEach unit can be in state 1 or 0Units update state by processing inputs of

neighbors and own state

Start with random configuration and let system evolve for 2N time steps

Do all units converge to correct classification?

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Majority rule

PNAS 101, 12085 (2004)

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GKL Rule

Majority rule

PNAS 101, 12085 (2004)

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Majority rule: Phase transition

PNAS 101, 12085 (2004)

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Efficiency increases with size

PNAS 101, 12085 (2004)