1. What is a "gene expression signature" for a tumor?
A collection of genes that are expressed consistently higher or lower in the tumor than is the population norm for non-tumorous tissue of the same type.
These techniques allow simultaneous analysis of the expression of many genes. Patterns of increased or decreased expression is associated with disease may then be identified and may contribute to improved diagnosis and prognosis.
3. To what 2 aspects of a usability assessment should the word "representative" apply?
(1) Representative tasks
(2) Representative users
(1) Have teens test the program, not physicians;
(2) select specific representative tasks for the assessment (not just "try the program out"); and
(3) observe the participants using the program and have them think aloud during the session rather than e-mail comments.
If we assume that each gene is independent and occurs in a normally distributed population, then one might expect approximately 5% of 40 000 or 2000 genes to appear over expressed or under expressed.
True
False