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Sample A: Cover Page of Thesis, Project, or Dissertation Proposal

Sample A: Cover Page of Thesis, Project, or Dissertation Proposal

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a. A filter based on how many probes contribute to the overall intensity, compared<br />

to the group mean, using only those probes that survived the above pipeline.<br />

Arrays f<strong>or</strong> which this mean exceeded ±2 standard deviations <strong>of</strong> the group (<strong>or</strong><br />

class) mean were excluded from further analysis.<br />

b. A filter based on the mean signal per probe, relative to the dataset mean. Arrays<br />

f<strong>or</strong> which this value exceeded ±2 standard deviations <strong>of</strong> the dataset mean were<br />

excluded from further analysis.<br />

II. ProbeSets-per-<strong>Sample</strong><br />

a. This filter determines how many ProbeSets contribute to the overall sample<br />

intensity, compared to the group mean, using only those probes that survived the<br />

above pipeline. Arrays where this mean exceeded -1.5 standard deviations <strong>of</strong> the<br />

dataset mean were excluded from further analysis. <strong>Sample</strong>s possessing the<br />

lowest surviving ProbeSets were removed m<strong>or</strong>e aggressively, since these samples<br />

will most limit the population <strong>of</strong> ProbeSets in the final dataset.<br />

b. The second filter determines the mean signal per ProbeSet, relative to the dataset<br />

mean. Arrays in which this value exceeded ±2 standard deviations <strong>of</strong> the group<br />

(<strong>or</strong> class) mean were excluded from further analysis.<br />

The above two filters were perf<strong>or</strong>med in parallel, not sequentially, so there is no <strong>or</strong>der <strong>of</strong><br />

operations dependence: failing either test was sufficient to eliminate the sample from the pool.<br />

Probeset aggregations had the statistical rig<strong>or</strong> <strong>of</strong> 4 probes per probeset enf<strong>or</strong>ced per individual<br />

sample described in the previous section. The filter in IIa is less rig<strong>or</strong>ous than the others, in part<br />

because <strong>of</strong> a desire to retain m<strong>or</strong>e samples f<strong>or</strong> the final comparison, accepting that later pruning<br />

might be required.<br />

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