proc GLM;
assuming A has 5 levels.
contrast 'A LINEAR & QUADRATIC'
a -2 -1 0 1 2------ I understand this is linear .
a 2 -1 -2 -1 2 ---------- Why this is QUADRATIC ?
L**********A 发帖数: 7115
2
google ORTHOGONAL POLYNOMIAL COEFFICIENTS
【在 v*******g 的大作中提到】 : proc GLM; : assuming A has 5 levels. : contrast 'A LINEAR & QUADRATIC' : a -2 -1 0 1 2------ I understand this is linear . : a 2 -1 -2 -1 2 ---------- Why this is QUADRATIC ?
v*******g 发帖数: 334
3
Thanks, i did .
Ok they're COEFFICIENTs of ( A+B)^2 or (A+B+C) ^2
but why the it has QUADRATIC effect?
【在 L**********A 的大作中提到】 : google ORTHOGONAL POLYNOMIAL COEFFICIENTS
