Title
Cooperative photometric redshift estimation.
Abstract
In the modern galaxy surveys photometric redshifts play a central role in a broad range of studies, from gravitational lensing and dark matter distribution to galaxy evolution. Using a dataset of similar to 25, 000 galaxies from the second data release of the Kilo Degree Survey (KiDS) we obtain photometric redshifts with five different methods: (i) Random forest, (ii) Multi Layer Perceptron with Quasi Newton Algorithm, (iii) Multi Layer Perceptron with an optimization network based on the Levenberg-Marquardt learning rule, (iv) the Bayesian Photometric Redshift model (or BPZ) and (v) a classical SED template fitting procedure (Le Phare). We show how SED fitting techniques could provide useful information on the galaxy spectral type which can be used to improve the capability of machine learning methods constraining systematic errors and reduce the occurrence of catastrophic outliers. We use such classification to train specialized regression estimators, by demonstrating that such hybrid approach, involving SED fitting and machine learning in a single collaborative framework, is capable to improve the overall prediction accuracy of photometric redshifts.
Year
DOI
Venue
2016
10.1017/S1743921317001296
IAU Symposium Proceedings Series
Keywords
Field
DocType
methods: data analysis,methods: statistical,catalogs
Dark matter,Astrophysics,Redshift,Algorithm,Galaxy formation and evolution,Multilayer perceptron,Gravitational lens,Galaxy,Physics,Photometric redshift,Estimator
Conference
Volume
Issue
ISSN
12
S325
1743-9213
Citations 
PageRank 
References 
0
0.34
0
Authors
8