I have this residual vs fitted values plot in R, and it should show a scatter of points with constant variance and mean 0. The mean 0 part seems to hold, but there is quite a clear diamond shape for the variance...
I have tried raising the response variable to a power <1 and a log...
Ah thanks, that's pretty helpful. I guess it makes sense because the rate of change of the gradient is greatest! Yeah but I've got an assignment that is all based around the composite trapezoidal rule and developments on it..
Thanks again.
Hey, thanks for your response, the integrals we are dealing with are actually well defined though.
I wrote a MATLAB program that would take the uniform mesh over [0,1] and raise it to a power eg
mesh = ((0:J)/J)^x, so that the points were more concentrated at the start or end depending on...
Hi guys, I'm using a composite trapezoidal rule to approximate the integral of functions. Up till now I have been using a uniform composite mesh, ie, there are J intervals, each interval being 1/J wide (since the integral is between 0 and 1).
How do I find the most efficient non-uniform mesh...