1 / 15

Exploratory Data Analysis

Exploratory Data Analysis. July 19, 2004 NGA Workshop. Step 1: For each earthquake, fit data to the following model (functional form used by Sadigh et al.). M = Earthquake magnitude R j = Closest distance to fault All soil types are lumped together.

hensleys
Download Presentation

Exploratory Data Analysis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Exploratory Data Analysis July 19, 2004 NGA Workshop

  2. Step 1: For each earthquake, fit data to the following model (functional form used by Sadigh et al.) M = Earthquake magnitude Rj = Closest distance to fault All soil types are lumped together

  3. C5 and C6 can’t be reliably estimated for most earthquakes  fixed to the values of Sadigh et al. (1997) • 172 earthquakes  172 x 2 = 344 unknown coefficients • Rj < 70 km • Freefield records • California data vs. worldwide data

  4. Step 2: Examine estimated C1 and C4 for magnitude effects and functional form.

  5. Step 3: • Modify the basic model to • C1 C1 + C2 M + C3 (M-8.5)2.5 • C4 C4 + C5 M • Repeat regression

  6. Step 4: • Examine estimated coefficientsfor • Magnitude scaling at short distances to large-magnitude earthquakes • Style of faulting effect • Effects of coseismic surface faulting

  7. Step 4: • Examine residualsfor • Site classification and site effects • FW/HW effects • Directivity effects

  8. Observed trend may be explained by more than one explanatory variables • Z1.5 ~ Vs30 (NEHRP) • Style of faulting ~ Surface Rupture • FW/HW ~ Directivity

  9. Y Cos()

  10. No Yes Unknown SS 17 17 38 NM 3 5 14 RV 18 4 11 RV-OB 7 3 1 NM-OB 1 1 4 Unknown 0 0 28

  11. Exploratory • Outliers do show up

More Related