Agner Fog (2007, 2008) has suggested that the best way to avoid confusion is to use the name Wallenius' noncentral hypergeometric distribution for the distribution of a biased urn model where a predetermined number of items are drawn one by one in a competitive manner, while the name Fisher's noncentral hypergeometric distribution is used where items are drawn independently of each other, so that the total number of items drawn is known only after the experiment. The names refer to Kenneth Ted Wallenius and R. A. Fisher who were the first to describe the respective distributions.