Overview of the Working Group for the Development of Regional Earthquake Likelihood Models (RELM)

2007 ◽  
Vol 78 (1) ◽  
pp. 7-16 ◽  
Author(s):  
E. H. Field
Keyword(s):  
Working Group ◽  
Earthquake Likelihood Models ◽  
Regional Earthquake

scholarly journals Implications of the Regional Earthquake Likelihood Models test of earthquake forecasts in California

2012 ◽  
Vol 2 (2) ◽  
pp. 10 ◽  
Author(s):  
Michael Karl Sachs ◽  
Ya-Ting Lee ◽  
Donald Turcotte ◽  
James R. Holliday ◽  
John B. Rundle
Keyword(s):  
Conditional Probability ◽  
Mean Value ◽  
Test Area ◽  
Test Period ◽  
Future Earthquake ◽  
The Mean ◽  
The One ◽  
Earthquake Likelihood Models ◽  
Regional Earthquake

The Regional Earthquake Likelihood Models (RELM) test was the first competitive comparison of prospective earthquake forecasts. The test was carried out over 5 years from 1 January 2006 to 31 December 2010 over a region that included all of California. The test area was divided into 7682 0.1°x0.1° spatial cells. Each submitted forecast gave the predicted numbers of earthquakes <em>N<sub>emi</sub></em> larger than <em>M</em>=4.95 in 0.1 magnitude bins for each cell. In this paper we present a method that separates the forecast of the number of test earthquakes from the forecast of their locations. We first obtain the number <em>N<sub>em</sub></em> of forecast earthquakes in magnitude bin <em>m</em>. We then determine the conditional probability <em>λ<sub>emi</sub></em>=<em>N<sub>emi</sub>/</em><em>N<sub>em</sub></em> that an earthquake in magnitude bin <em>m</em> will occur in cell <em>i</em>. The summation of <em>λ<sub>emi</sub></em> over all 7682 cells is unity. A random (no skill) forecast gives equal values of <em>λ<sub>emi</sub></em> for all spatial cells and magnitude bins. The <em>skill</em> of a forecast, in terms of the location of the earthquakes, is measured by the success in assigning large values of <em>λ<sub>emi</sub></em> to the cells in which earthquakes occur and low values of <em>λ<sub>emi</sub></em> to the cells where earthquakes do not occur. Thirty-one test earthquakes occurred in 27 different combinations of spatial cells <em>i</em> and magnitude bins <em>m</em>, we had the highest value of <em>λ<sub>emi</sub></em> for that <em>mi</em> cell. We evaluate the performance of eleven submitted forecasts in two ways. First, we determine the number of <em>mi</em> cells for which the forecast <em>λ<sub>emi</sub></em> was the largest, the best forecast is the one with the highest number. Second, we determine the mean value of <em>λ<sub>emi</sub></em> for the 27 <em>mi</em> cells for each forecast. The best forecast has the highest mean value of <em>λ<sub>emi</sub></em>. The success of a forecast during the test period is dependent on the allocation of the probabilities λemi between the mi cells, since the sum over the mi cells is unity. We illustrate the forecast distributions of <em>λ<sub>emi</sub></em> and discuss their differences. We conclude that the RELM test was successful in illustrating the choices required when a forecast of the location of a future earthquake is made.

scholarly journals First Results of the Regional Earthquake Likelihood Models Experiment

2010 ◽  
pp. 5-22 ◽  
Author(s):  
Danijel Schorlemmer ◽  
◽  
J. Douglas Zechar ◽  
Maximilian J. Werner ◽  
Edward H. Field ◽  
...  
Keyword(s):  
First Results ◽  
Earthquake Likelihood Models ◽  
Regional Earthquake

scholarly journals Results of the Regional Earthquake Likelihood Models (RELM) test of earthquake forecasts in California

2011 ◽  
Vol 108 (40) ◽  
pp. 16533-16538 ◽  
Author(s):  
Y.-T. Lee ◽  
D. L. Turcotte ◽  
J. R. Holliday ◽  
M. K. Sachs ◽  
J. B. Rundle ◽  
...  
Keyword(s):  
Earthquake Likelihood Models ◽  
Regional Earthquake

scholarly journals Regional Earthquake Likelihood Models II: Information Gains of Multiplicative Hybrids

2014 ◽  
Vol 104 (6) ◽  
pp. 3072-3083 ◽  
Author(s):  
D. A. Rhoades ◽  
M. C. Gerstenberger ◽  
A. Christophersen ◽  
J. D. Zechar ◽  
D. Schorlemmer ◽  
...  
Keyword(s):  
Earthquake Likelihood Models ◽  
Regional Earthquake

Regional Earthquake Likelihood Models I: First-Order Results

2013 ◽  
Vol 103 (2A) ◽  
pp. 787-798 ◽  
Author(s):  
J. D. Zechar ◽  
D. Schorlemmer ◽  
M. J. Werner ◽  
M. C. Gerstenberger ◽  
D. A. Rhoades ◽  
...  
Keyword(s):  
First Order ◽  
Earthquake Likelihood Models ◽  
Regional Earthquake

scholarly journals First Results of the Regional Earthquake Likelihood Models Experiment

2010 ◽  
Vol 167 (8-9) ◽  
pp. 859-876 ◽  
Author(s):  
Danijel Schorlemmer ◽  
◽  
J. Douglas Zechar ◽  
Maximilian J. Werner ◽  
Edward H. Field ◽  
...  
Keyword(s):  
First Results ◽  
Earthquake Likelihood Models ◽  
Regional Earthquake

2.2. Working Group 2: Conceptual Definitions of Reference Coordinate Systems for Earth Dynamics

1975 ◽  
Vol 26 ◽  
pp. 21-26
Keyword(s):  
Coordinate System ◽  
Working Group ◽  
General Character ◽  
Coordinate Systems ◽  
Reference Coordinate System ◽  
Group 2 ◽  
Definition Of ◽  
Earth Dynamics

An ideal definition of a reference coordinate system should meet the following general requirements:1. It should be as conceptually simple as possible, so its philosophy is well understood by the users.2. It should imply as few physical assumptions as possible. Wherever they are necessary, such assumptions should be of a very general character and, in particular, they should not be dependent upon astronomical and geophysical detailed theories.3. It should suggest a materialization that is dynamically stable and is accessible to observations with the required accuracy.

Models of Thermodynamic Properties of Prominences

1979 ◽  
Vol 44 ◽  
pp. 349-355
Author(s):  
R.W. Milkey
Keyword(s):  
Thermodynamic Properties ◽  
Mass Transport ◽  
Emission Spectrum ◽  
Thermodynamic Parameters ◽  
Working Group ◽  
Physical Processes ◽  
Theoretical Concepts ◽  
Group 3 ◽  
Observational Techniques

The focus of discussion in Working Group 3 was on the Thermodynamic Properties as determined spectroscopically, including the observational techniques and the theoretical modeling of physical processes responsible for the emission spectrum. Recent advances in observational techniques and theoretical concepts make this discussion particularly timely. It is wise to remember that the determination of thermodynamic parameters is not an end in itself and that these are interesting chiefly for what they can tell us about the energetics and mass transport in prominences.

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