On the realistic validation of photometric redshifts
On the realistic validation of photometric redshifts
复制标题
关于光度红移的现实验证
DOI：
--
复制
发表时间：
2017
期刊：
影响因子：
--
通讯作者：
A. Krone
中科院分区：
文献类型：
--
作者：
R. Beck;C. A. Lin;E. Ishida;Fabian Gieseke;R. S. D. Souza;R. S. D. Souza;M. Costa;M. Costa;M. Hattab;A. Krone
光度红移（photo-z）技术的发展和准确验证中遇到的两个主要问题是缺乏光谱覆盖的特征空间（例如颜色和幅度）和光度误差分布与光谱和光度样本之间的不匹配。虽然这些问题是众所周知的，目前没有标准的基准允许定量分析其对最终的photo-z估计的影响。在这项工作中，我们提出了两个星系目录，泰迪和快乐，使一个更苛刻和现实的测试photo-z方法。使用从斯隆数字巡天测光和光谱从收集的来源，我们构建了数据集，模拟的真实的光谱和光度样本的潜在概率分布之间的偏差。我们通过将这些目录提交给不同的photo-z方法（包括机器学习（ML）和模板拟合方法）的审查来展示这些目录的潜力。除了大多数ML算法在特征空间中缺失覆盖的情况下的预期不良结果之外，我们能够认识到全球模型在相同情况下的优越性，以及当不完全覆盖与光度误差的存在相交织时所有类型的方法的普遍失败-一种数据情况，z方法到目前为止还没有被训练来处理，这必须通过未来的大规模调查来解决。我们的目录代表了第一个允许直接实施此类测试的受控环境。这些数据可以在COINtoolbox中公开获得（此https URL）。
Two of the main problems encountered in the development and accurate validation of photometric redshift (photo-z) techniques are the lack of spectroscopic coverage in feature space (e.g. colours and magnitudes) and the mismatch between photometric error distributions associated with the spectroscopic and photometric samples. Although these issues are well known, there is currently no standard benchmark allowing a quantitative analysis of their impact on the final photo-z estimation. In this work, we present two galaxy catalogues, Teddy and Happy, built to enable a more demanding and realistic test of photo-z methods. Using photometry from the Sloan Digital Sky Survey and spectroscopy from a collection of sources, we constructed datasets which mimic the biases between the underlying probability distribution of the real spectroscopic and photometric sample. We demonstrate the potential of these catalogues by submitting them to the scrutiny of different photo-z methods, including machine learning (ML) and template fitting approaches. Beyond the expected bad results from most ML algorithms for cases with missing coverage in feature space, we were able to recognize the superiority of global models in the same situation and the general failure across all types of methods when incomplete coverage is convoluted with the presence of photometric errors - a data situation which photo-z methods were not trained to deal with up to now and which must be addressed by future large scale surveys. Our catalogues represent the first controlled environment allowing a straightforward implementation of such tests. The data are publicly available within the COINtoolbox (this https URL).
影响因子：
6.5
作者：
H. Hildebrandt;H. Hildebrandt;C. Wolf;N. Benı́tez
通讯作者：
H. Hildebrandt;H. Hildebrandt;C. Wolf;N. Benı́tez
影响因子：
4.8
作者：
de Souza, R. S.;Hilbe, J. M.;Killedar, M.
通讯作者：
Killedar, M.
DOI：
10.1016/j.ascom.2015.04.002
发表时间：
2014-09
期刊：
Astron. Comput.
影响因子：
--
作者：
R. S. Souza;E. Cameron;M. Killedar;J. Hilbe;R. Vilalta;U. Maio;V. Biffi;B. Ciardi;J. Riggs
通讯作者：
R. S. Souza;E. Cameron;M. Killedar;J. Hilbe;R. Vilalta;U. Maio;V. Biffi;B. Ciardi;J. Riggs