After completing her undergraduate degree in Biology from the University of Maryland, College Park, Merrill joined the School of Public Health at the University of California at Berkeley. She received her M.P.H. in Epidemiology and Biostatistics in May 2003. She received her Ph.D. in Biostatistics under the supervision of Professor Mark J. van der Laan in May 2006. Her dissertation was entitled "Resampling Based Multiple Testing Methodology and Biological Application". At the statistics department graduation, Merrill was honored with the Evelyn Fix Memorial Award for her research on methods for the analysis of genomic data. Merrill was also selected as the Chin Long Chiang Biostatistics Student of the Year for 2006.
Merrill is currently a biostatistician in the Biostatistics/BioOncology Department at Genenetech Inc. in South San Francisco.