@article{dd3144afbf384955bb876eeaaa8f836e,
title = "Multivariate conversion of moment magnitude for small-to-moderate-magnitude earthquakes in Iran",
abstract = "Homogeneous estimates of moment magnitude (M) for small-to-moderate-magnitude (SMM) earthquakes are important to assess regional ground motion compared to global models. However, an estimate of M was available for only 6% of the shallow crustal earthquakes in Iran from 1973 to 2013 in the database developed by the Pacific Earthquake Engineering Research Center. Therefore, this study evaluates the existing conversion models, from ML, Ms, and mb, to M, for M > 4.0 using the Iranian data set. Correlations between the residuals of these conversions were computed. A weighted estimate for M is presented that combines these conversion models using these correlations based on multivariate statistics. The conversion to M was improved with smaller standard deviations, especially when ML and mb were both available. The inverse-variance–weighted approach, which is common in practice, underestimates the standard deviations because it neglects the positive correlations between these variables.",
author = "Tadahiro Kishida and Sahar Derakhshan and Sifat Muin and Darragh, {Robert B.} and Yousef Bozorgnia and Nicolas Kuehn and Kwak, {Dong Youp}",
note = "Funding Information: This study was conducted during the tenure of several authors at the Pacific Earthquake Engineering Research Center (PEER) at the University of California, Berkeley. We thank the Building & Housing Research Center (BHRC), especially Dr. Shekarchizadeh and Mr. Farzanegan, for providing us with uncorrected earthquake time series data. Also, the encouragement of Dr. Glenn Schweitzer of the U.S. National Academy of Sciences is greatly appreciated. The authors are grateful for the comments by Dr. Shoja-Taheri. Thoughtful reviews by Dr. Ben Edwards and two anonymous reviewers also improved the paper. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect those of the sponsoring agencies. Publisher Copyright: {\textcopyright} 2018 Earthquake Engineering Research Institute.",
year = "2018",
month = feb,
doi = "10.1193/050917EQS086M",
language = "British English",
volume = "34",
pages = "313--326",
journal = "Earthquake Spectra",
issn = "8755-2930",
publisher = "Earthquake Engineering Research Institute",
number = "1",
}