book_3_19.m
Use rfplot after transform.
load ganglion x = Area; y = CPratio; pow = 1; y = log2(y); fitx= x; p = polyfit(x,y,pow); fity = polyval(p,fitx); residual = y(:)-fity(:); % Resdiual fit plot rfplot(fity,residual,'Residual Log_2 CP Ratio')

Use rfplot after transform.
load ganglion x = Area; y = CPratio; pow = 1; y = log2(y); fitx= x; p = polyfit(x,y,pow); fity = polyval(p,fitx); residual = y(:)-fity(:); % Resdiual fit plot rfplot(fity,residual,'Residual Log_2 CP Ratio')