We develop a non-parametric inverse method to investigate the star formation rate , the metallicity evolution and the reddening properties of galaxies based on their spectral energy distributions ( SEDs ) .
This approach allows us to clarify the level of information present in the data , depending on its signal-to-noise ratio ( S/N ) .
When low resolution SEDs are available in the ultraviolet , optical and near-IR wavelength ranges together , we conclude that it is possible to constrain the star formation rate and the effective dust optical depth simultaneously with a signal-to-noise ratio of 25 .
With excellent signal-to-noise ratios , the age-metallicity relation can also be constrained . We apply this method to the well-known nuclear starburst in the interacting galaxy NGC 7714 .
We focus on deriving the SFR and the reddening law .
We confirm that classical extinction models can not provide an acceptable simultaneous fit of the SED and the lines .
We also confirm that , with the adopted population synthesis models and in addition to the current starburst , an episode of enhanced star formation that started more than 200 Myr ago is required .
As the time elapsed since the last interaction with NGC 7715 , based on dynamical studies , is about 100 Myr , our result reinforces the suggestion that this interaction might not have been the most important event in the life of NGC 7714 .