The Top 25 global research organizations include companies such as The Nielsen Company, the Ipsos Group, and Harris Interactive. Data about global research revenues (in US$ millions) and the number of full-time employees have been collected for 2007.1 The question that interests the researcher is this: Do research companies with more employees have larger revenues? In this data set, which is the response variable and which is the explanatory variable? Create a scatter diagram, estimate the least squares regression equation, and interpret it.