=+19. The invasive diatom species Didymosphenia geminata has the potential to inflict substantial ecological and economic damage in rivers. The article

“Substrate Characteristics Affect Colonization by the Bloom-Forming Didymosphenia geminata”

(Aquatic Ecology, 2010: 33–40) described an investigation of colonization behavior. One aspect of particular interest was whether y 5 colony density was related to x 5 rock surface area. The article contained a scatterplot and summary of a regression