Smith's Salience Index (S)

Smith's salience index, conventionally written S, is the standard statistic for summarizing free-list data: for each item it combines how many informants mentioned the item with how early the item appeared in their lists. Within a single list each item receives a local salience equal to the number of items below it divided by the list length, so the first item scores highest and the last scores lowest; S is then the average of that local salience across the entire sample, counting zero for informants who never listed the item. The result is a single per-item number that ranks the items of a cultural domain by their joint frequency-and-priority prominence.