The "rank product" is a statistical technique, used for detecting differentially regulated genes in replicated microarray experiments. The technique has achieved widespread acceptance and is now used more broadly, in such diverse fields as RNAi analysis, proteomics, and machine learning. The "rank product" technique may be used in ranking users (in social networks) and items (such as Amazon.com).Given large set of genes, users, or items, in this webcast I will present two distinct Spark solutions: (using groupByKey() and combineByKey()) for solving the "rank product".