STATISTICIAN
statistician, actuary
(noun) someone versed in the collection and interpretation of numerical data (especially someone who uses statistics to calculate insurance premiums)
statistician, mathematical statistician
(noun) a mathematician who specializes in statistics
Source: WordNet® 3.1
Noun
statistician (plural statisticians)
A person who compiles, interprets, or studies statistics.
(mathematics) A mathematician with a specialty of statistics.
Source: Wiktionary
Stat`is*ti"cian, n. Etym: [Cf. F. statisticien.]
Definition: One versed in statistics; one who collects and classifies facts
for statistics.
Source: Webster’s Unabridged Dictionary 1913 Edition