Estimation of Cellular and Genetic Diversity

Within-tumor heterogeneity has long been a focus in characterizing cancers. Recent advances in fluorescent in situ hybridization (FISH) have made it possible to examine copy numbers at cellular level and analyze diversity within tumor cells. This has brought various statistical challenges some of which were faced by ecologists before. In this talk I will discuss the bias in Shannon’s index, the most popular measure of diversity, due to the total number of types being unobservable. A maximum-entropy approach seems to reduce the bias when sample sizes are modest relative to the total number of types. Data from a recent publication on the diversity of in situ and invasive breast tumors will be used for demonstration. (This is joint work with Elza Erkip of New York University.)

Date & Time(s)


307 East 63rd Street, 3rd Floor Conference Room


Mithat Gonen
Associate Attending Biostatistician
Epidemiology and Biostatistics
Memorial Sloan Kettering Cancer Center