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(SHA) and seismic risk analysis (SRA). However, earthquake catalogs are often
biased due to incomplete reporting for small magnitude earthquakes as well as for
large earthquakes having long return periods. Hence, completeness analysis plays
an important role as incomplete catalogs cause under-sampling and erroneous
seismicity parameter values. On the other hand, earthquake magnitudes are reported
in different magnitude scales, and come from a variety of sources. It is also
desirable to form homogenous catalogs by converting different magnitude scales
into a single one for reliable long-term SHA. Another improvement on data could
be declustering, that is, the process of separating the seismicity catalog into fore-
shocks, mainshocks, and aftershocks used for SHA and in earthquake prediction
models.
After ensuring the quality of data, the next step is typically to model earth-quake
magnitudes, to determine models for earthquake forecasting and hazard assessment
and their parameter estimation. Estimation of maximum magnitude, de
ned as the
upper limit of magnitude for a given seismogenic zone or entire region, is also
required for many earthquake engineering applications. Precise modelling and
estimation of such seismicity parameters are of primary importance since the
evaluation of seismicity and assessment of seismic hazards depend on them.
Next, time independent, time-dependent or time/space-dependent seismicity
models, which take the above-mentioned seismicity parameters as input, are used to
describe, analyse, and forecast the probabilities of earthquake occurrences. To
evaluate the epistemic uncertainty involved in SHA, logic-tree and sensitivity
analyses, which are necessary to identify the input parameters that have the greatest
impact on hazard assessment, can be conducted.
SHA and SRA completely depend on the processes discussed so far, where the
former describes the phenomena generated by earthquakes that have potential to
cause harm, while the latter is the probability of experiencing a speci
ed level of
seismic hazard in a given time period. Both can be used to construct hazard maps
and calculate potential risks. At this stage, the evaluation of proposed earthquake
prediction and forecasting methods enter the scene. An earthquake prediction
speci
es the time, location, and strength of an earthquake. On the other hand, an
earthquake forecast is a probabilistic determination of an earthquake, based on
some variables such as frequency and magnitude of past events in an area over a
period of time. Both are fundamental components to mitigate seismic risk.
With this large content, these statistical seismology methods and models are
highly bene
ted by seismologists. Meanwhile, its outcomes are also the interest of
planners, lenders, municipalities, construction companies, and insurers, as it pro-
vides insights for constructing and revising seismic hazard maps and potential risks,
updating state building codes, revising construction standards, renovation of risky
structures, updating models of determining insurance premiums, and protecting
energy facilities, major energy transmission lines, and transportation infrastructures.
Furthermore, they are also considered by social and psychological studies.
One of the most widely-used software tools in this
field is EZ-FRISK (2014). It
is a commercial product that supports probabilistic and deterministic approaches for
SHA calculations. FRISK88M, another commercial product, provides advanced
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