Part 13- Simple linear regression - The University of Jordan

University of Jordan Agricultural Statistic (605150)Faculty of AgricultureDr. Amer SalmanDept. of Agri. Econ. & Agribusinessxمعناه أن التغير الحاصل في yنتيجة التغير الحاصل فييمكن تفسيره بنسبة صحة مقدارها %81.67 والباقي يعزى إلى عوامل2Rأخرى.‏Example (13 – 9):The following table shows the relation between N (x) and Potato production (y). Find theregression equation and the coefficient of determination R 2 and sketch the curveaccording to your results.XiYixiX i− XyiY i− Yx y 2i i xiYˆi2ei( Y − Y ) 2iˆi2Xi2yi( Y Y) 2i−1 1 -2.5 -1.75 4.375 6.25 1.115 0.0313 1 3.0633 2 -0.5 -0.75 0.375 0.25 2.423 0.1759 9 0.5634 4 0.5 1.25 0.625 0.25 3.077 0.852 16 1.5636 4 2.5 1.25 3.125 6.25 4.385 0.1479 36 1.563X =3.5 Y =2.75 8.5 13 1.1923 6.75Yˆ= βo+ β1x ; β1= 0.654, βo= 0.461Yˆ = 0.461+0. 654x (Regression equation)Yβ 1β oX2∑ e < ∑R22iy i=∑∑e2i1−2yi1.1923≅ 1−= 0.8236.75- 17 -