Bayesian data analysis: Difference between revisions

No edit summary
Line 36: Line 36:
:<math>p(\alpha|D) = \frac{p(D|\alpha)p(\alpha)}{p(D)}</math>
:<math>p(\alpha|D) = \frac{p(D|\alpha)p(\alpha)}{p(D)}</math>
where ''D'' represents the available data.
where ''D'' represents the available data.
The likelihood ''p(D|&alpha;)'' speficies the probability of a specific measurement outcome ''D'' for a given choice of parameters ''&alpha;''.
The likelihood ''p(D|&alpha;)'' specifies the probability of a specific measurement outcome ''D'' for a given choice of parameters ''&alpha;''.
The advantage of the parametric representation is that the abstract 'system state' is reduced to a finite set of parameters, greatly facilitating numerical analysis.
The advantage of the parametric representation is that the abstract 'system state' is reduced to a finite set of parameters, greatly facilitating numerical analysis.
This parametrization may involve, e.g., smooth (orthogonal) expansion functions such as [[:Wikipedia:Fourier-Bessel_series|Fourier-Bessel functions]], or discretely defined functionals on a grid.
<ref>[[doi:10.1088/0741-3335/50/8/085002|J. Svensson et al, ''Current tomography for axisymmetric plasmas'', Plasma Phys. Control. Fusion '''50''' (2008) 085002</ref>


=== Maximization ===
=== Maximization ===