Method of path coefficients, 1921

Here are the original 16 models published by Sewall Wright in 1921 in 'Journal of agricultural research'. Enjoy!

PS: He wasn't a 'statistician'... his title read: "Senior Animal Husbandman in Animal Genetics, Bureau of Animal Industry, United States Department of Agriculture" !

Wright, S. (1921). Correlation and causation. Part I Method of path coefficients. Journal of agricultural research, 20(7), 557-585. [CITED BY  2119, GOOGLE.SCOLAR; Aug.2018: 4,415 times!].

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& ["Let O represent residual factors." in Wright, S. (1934). The Method of Path Coefficients, The Annals of Mathematical Statistics, 5(3), 161-215.]

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