Plot the Posterior PDFsΒΆ
You can examine the posterior probability density functions to get a
quantitative look at the results of the model fitting process using
visualize.posteriorPDF()
:
import visualize
visualize.posteriorPDF()
This will produce a series of histograms showing the posterior probability distribution functions for every parameter in the model.
This routine also prints the average and 1-sigma rms uncertainty on each parameter of the model. We can see from the posterior PDF histograms that XMM101 appears to be elongated (axial ratio = 0.52 +/- 0.11) and has a total flux density at 870um of 8.76 +/- 0.24 mJy. It has an effective radius of 0.085 +/- 0.010 arcsec, which translates to a FWHM of 0.2 arcsec. At z=2 (the actual redshift of this object is unknown currently, but the Herschel photometry indicates z~2) this corresponds to a physical size of 1.7 kpc.
You can also see how the posterior PDF of every parameter in the
model changes as a function of iteration using visualize.evolvePDF()
:
visualize.evolvePDF()
This function essentially produces a posteriorPDF every stepsize
iterations. The default is stepsize = 50000
. You can then view the
evolution in the PDF using a viewer application like Preview.