如何计算截距？

shiyiming

有没有用sas做过回归分析的朋友，能帮我讲一下要用到的计算截距？
谢谢！

shiyiming

For linear regression case:

x and y are two variables under consideration

if the least-squares line is y=a+bx (a is intercept and b is slope)

then b=r*sy/sx & [b:afa1f]a=ybar-b*xbar[/b:afa1f]

xbar and ybar are mean of x and y respectively

sx and sy are sample standard deviation



SAS/INSIGHT---(Analyze-Fit(Y X))---choose [b:afa1f]X [/b:afa1f]variable and [b:afa1f]Y[/b:afa1f] variable, then you can get a regression line and regression equation