Although he was successful at Cambridge, he had not yet found his vocation in life, though he was interested in mathematical physics. He also attened one lecture on statistics by G Udny Yule. He read at this time Karl Pearson's Mathematical Contributions ot the Theory of Evolution. Shortly before the War in 1914, Fisher first came into contact with Karl Pearson. About 1915 he was offered 2 jobs. One was the post of chief statistition under Karl Pearson at the illustrious Galton Laboratory, and the other was for the Rothamsted experimental agricultural sation with the opportunity for building up a statistical laboratory. Fisher unhesitatingly accepted Rothamsted. At Rothamsted he found his real vocation in life. He continued his work on sampling distributions, and in 1921completed the classic memoir on Mathematical Foundations of Theoretical Statistics which was intended to supply the framework of current statistical theory. The z-test of significance and the arithmetic procedure known as the analysis of variance, ANOVA.. Statistical Methods for Reseach Workers was first published in 1925.