Related research interest Luis A. N. Amaral Dept. Chemical and Biological Engineering Northwestern...

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)