Collected Notes on Solutions to SPlus worksheets: DRAFT Summary: Collected Notes on Solutions to S­Plus worksheets: DRAFT P.M.E.Altham, Statistical Laboratory, University of Cambridge. December 12, 2006 Not to be quoted without acknowledgement, please. P.M.E.Altham@statslab.cam.ac.uk I originally constructed these draft solutions for our MPhil students in about 1998. I tended to make very limited use of graphics at that time, so now I have more leisure I will add the odd extra graph here and there, and maybe expand the explanation in places. Notes on solution to worksheet 1. First, Figure 1 shows the plot of y against x. You will see that although y is certainly an increasing function of x, this dependence is just possibly quadratic rather than linear. Here is the linear regression (the output is slightly edited to save paper). Call: lm(formula = y ~ x) Coefficients: Value Std. Error t value Pr(>|t|) (Intercept) ­9.4543 0.6553 ­14.4283 0.0000 x 1.6579 0.0753 22.0139 0.0000 Collections: Mathematics