Re: [Numpy-discussion] Fitting a curve on a log-normal distributed data

2009-11-21 Thread Gökhan Sever
One more update on this subject. I have been looking through some of the papers on this topic, and I have finally found exactly what I need in this paper: Hussein, T., Dal Maso, M., Petaja, T., Koponen, I. K., Paatero, P., Aalto, P. P., Hameri, K., and Kulmala, M.: Evaluation of an automatic algor

Re: [Numpy-discussion] Fitting a curve on a log-normal distributed data

2009-11-20 Thread Gökhan Sever
On Thu, Nov 19, 2009 at 9:12 PM, Ian Mallett wrote: > Hello, > > My analysis shows that the exponential regression gives the best result > (r^2=87%)--power regression gives worse results (r^2=77%). Untransformed > data gives r^2=76%. > > I don't think you want lognorm. If I'm not mistaken, that

Re: [Numpy-discussion] Fitting a curve on a log-normal distributed data

2009-11-19 Thread Ian Mallett
Hello, My analysis shows that the exponential regression gives the best result (r^2=87%)--power regression gives worse results (r^2=77%). Untransformed data gives r^2=76%. I don't think you want lognorm. If I'm not mistaken, that fits the data to a log(normal distribution random variable). So,

Re: [Numpy-discussion] Fitting a curve on a log-normal distributed data

2009-11-17 Thread Gökhan Sever
On Tue, Nov 17, 2009 at 12:13 AM, Ian Mallett wrote: > Theory wise: > -Do a linear regression on your data. > -Apply a logrithmic transform to your data's dependent variable, and do > another linear regression. > -Apply a logrithmic transform to your data's independent variable, and do > another

Re: [Numpy-discussion] Fitting a curve on a log-normal distributed data

2009-11-16 Thread Ian Mallett
Theory wise: -Do a linear regression on your data. -Apply a logrithmic transform to your data's dependent variable, and do another linear regression. -Apply a logrithmic transform to your data's independent variable, and do another linear regression. -Take the best regression (highest r^2 value) an

[Numpy-discussion] Fitting a curve on a log-normal distributed data

2009-11-16 Thread Gökhan Sever
Hello, I have a data which represents aerosol size distribution in between 0.1 to 3.0 micrometer ranges. I would like extrapolate the lower size down to 10 nm. The data in this context is log-normally distributed. Therefore I am looking a way to fit a log-normal curve onto my data. Could you pleas