Zipf's Law in Importance of Genes for Cancer Classification Using Microarray Data

Details Zipf's Law in Importance of Genes for Cancer Classification Using Microarray Data Zipf's Law in Importance of Genes for Cancer Classification Using Microarray Data

2001-04-06

arxiv.org/abs/physics/0104028v1

W Li and Y Yang (2002), J. Theoretical Biology, 219(4):539-551.

Physics

Biological Physics

11 pages, 5 figures. submitted

Scientific paper

10.1006/jtbi.2002.3145

Microarray data consists of mRNA expression levels of thousands of genes under certain conditions. A difference in the expression level of a gene at two different conditions/phenotypes, such as cancerous versus non-cancerous, one subtype of cancer versus another, before versus after a drug treatment, is indicative of the relevance of that gene to the difference of the high-level phenotype. Each gene can be ranked by its ability to distinguish the two conditions. We study how the single-gene classification ability decreases with its rank (a Zipf's plot). Power-law function in the Zipf's plot is observed for the four microarray datasets obtained from various cancer studies. This power-law behavior in the Zipf's plot is reminiscent of similar power-law curves in other natural and social phenomena (Zipf's law). However, due to our choice of the measure of importance in classification ability, i.e., the maximized likelihood in a logistic regression, the exponent of the power-law function is a function of the sample size, instead of a fixed value close to 1 for a typical example of Zipf's law. The presence of this power-law behavior is important for deciding the number of genes to be used for a discriminant microarray data analysis.

Affiliated with

Also associated with

No associations

Rating

Zipf's Law in Importance of Genes for Cancer Classification Using Microarray Data does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Zipf's Law in Importance of Genes for Cancer Classification Using Microarray Data, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Zipf's Law in Importance of Genes for Cancer Classification Using Microarray Data will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-657462