Hi, I read data from a file. I'm trying to understand how to use Design.rcs by using simple test data first. I use 1000 integer values (1,...,1000) for x (the predictor) with some noise (x+.02*x) and I set the response variable y=x. Then, I try rcs and ols as follows:
m = ( sqrt(y1) ~ ( rcs(x1,3) ) ); #I tried without sqrt also f = ols(m, data=data_train.df); print(f); [I plot original x1,y1 vectors and the regression as in y <- coef2[1] + coef2[2]*x1 + coef2[3]*x1*x1] But this gives me a VERY bad fit: " Linear Regression Model ols(formula = m, data = data_train.df) n Model L.R. d.f. R2 Sigma 1000 4573 2 0.9897 0.76 Residuals: Min 1Q Median 3Q Max -4.850930 -0.414008 -0.009648 0.418537 3.212079 Coefficients: Value Std. Error t Pr(>|t|) Intercept 5.90958 0.0672612 87.86 0 x1 0.03679 0.0002259 162.88 0 x1' -0.01529 0.0002800 -54.60 0 Residual standard error: 0.76 on 997 degrees of freedom Adjusted R-Squared: 0.9897 " I appreciate any and all help! Sincerely, sp ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.