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Comment: Migrated to Confluence 5.3

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SVD on the entire 27k by 511 patients M value matrix, plot 1st eigenarray (u matrix) and "color" the points according to the dye with with each CpG was labeled:

Image Added

M value: analysis of red probes, identification of adjustment variables

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PCs

Batch

Center

Day

Month

Year

Amount

Concentr.

Row

Column

Stage

Grade

Age

1

2.2e-16

2.2e-16

2.2e-16

2.2e-16

2.2e-16

2.2e-16

0.0004486

5.882547e-02

6.881028e-02

0.32

0.27

0.1071

2

0.5383

0.3486

0.5577

0.9876

0.2710

0.04873

0.6482

0.2862026

0.4786892

0.31

0.10

0.006634

3

0.04048

0.05258

0.03756

0.01480

0.1233

0.1786

0.5335

0.55585676

0.25289498

0.50

0.35

0.5131

4

0.0003439

0.01709

0.0008948

0.0001387

0.5725

0.7225

0.5267

0.0516508987

0.1404578746

0.43

0.43

0.02168

Finally, the center effect needs to go. Variables to adjust for: batch, center, plate row, plate column. Percent Variance explained after the adjustment:

It looks like removing the batch and the plate row did help some with the center effect but the plate column effect is still significantly higher. Need to remove that.

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PCs

Batch

Center

Day

Month

Year

Amount

Concentr.

Row

Column

Stage

Grade

Age

1

0.936

7.104e-05

0.881

0.915

0.938

0.780

0.027

0.998

0.757

0.36

0.22

0.6967

2

1

0.7801

1.00

1.00

0.96

0.92

0.75

0.97

0.45

0.36

0.30

0.02479

3

1

0.04068

1.00

1.00

0.93

0.97

0.51

1.00

0.18

0.30

0.27

0.1425

Finally, the center effect needs to go. Variables to adjust for: batch, center, plate row, plate column. Percent Variance explained after the adjustment:
Image Added Image Added

Under 14%! Still large effect, look at the variables:

PCs

Batch

Center

Day

Month

Year

Amount

Concentr.

Row

Column

Stage

Grade

Age

1

0.9986

0.9998

0.993

0.987

0.963

0.897

0.042

0.999

0.433

0.39

0.34

0.8608

2

1

1

1.00

1.00

0.95

0.96

0.86

0.97

0.61

0.27

0.36

0.02406

3

1

1

1.00

1.00

0.84

0.96

0.50

1.00

0.75

0.33

0.45

0.3325

Now lets take a look at the outliers of the first eigengene (patients 6 vs 367):

Image Added

I guess it doesn't look too terrible. I also tried to remove all the listed variables as well as the first principal component and here is what I got in terms of the percent variance explained and the outliers: Image Added  Image Added
To me it looks worse than with the first principal component. Final: remove the batch, center, plate row and plate column from the data. 

M value: analysis of green probes, identification of adjustment variables

Percent Variance explained:

Image Added

PCs

Batch

Center

Day

Month

Year

Amount

Concentr.

Row

Column

Stage

Grade

Age

1

2.2e-16

2.2e-16

1.6e-61

5.7e-39

3.8e-31

1.6e-19

6.9e-04

3.2e-02

2.2e-01

0.36

0.17

0.2778

Remove the batch, center, plate row, plate column (also mask that one batch), looks at the first eigengene and the eigenarray:

Image Added Image Added

P values after the adjustment:

PCs

Batch

Center

Day

Month

Year

Amount

Concentr.

Row

Column

Stage

Grade

Age

1

0.999

0.9999

0.995

0.991

0.956

0.863

0.074

0.997

0.626

0.60

0.26

0.6206

Look at the outliers:
Image Added
Weird!
Do one more test and remove the first eigengene together with the variables above:
Image Added Image Added

Conclusion

Now scale (center=TRUE, scale=TRUE) bot datasets (red and green probes), combine them together for network construction.