To%20pool%20or%20not%20to%20pool%20your%20biological%20samples

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To pool or not to pool your biological samples

• Rafael A Irizarry

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Design I
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Design II or Big Mistake I
Assay
Subjects
mRNA Pool
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• If you pool you see
• Truth (average of individuas 1-3) (average of
  meas error 1-3)
• If you dont pool you see
• Y1Truth individual 1 meas error 1
• Y2Truth individual 2 meas error 2
• Y3Truth individual 3 meas error 3
• Each one has more variance than if you pool
  but average of Y1, Y2, Y3 should also be
• Truth (average of individuals 1-3) (average
  of meas error 1-3)
• But you also get to see variance of Y1, Y2, Y3!

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Problem with pooling everything
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Design I
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Design II
Subjects
mRNA Pool
Array
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Better than pooling everything
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Another Advantage

• Log(Y1 Y2 Y3)
• not equal to
• Log(Y1) Log(Y2) log(Y3)

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(No Transcript)
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Thanks!