Location Formal Error Scale Factor Calculator
Heuristic horizontal formal error: σ_h ≈ RMS·v_p·√(N/(N−4)).
Description
Heuristic horizontal formal error: σ_h ≈ RMS·v_p·√(N/(N−4)).
Location Formal Error Scale Factor Calculator is a focused tool for the following task. Heuristic horizontal formal error: σ_h ≈ RMS·v_p·√(N/(N−4)). It reports σ_h, Good? from the values you provide rather than inventing measurements, coefficients, or professional judgment that are not part of the input.
When to use Location Formal Error Scale Factor
Use this seismology calculation to reproduce a stated convention, screen observations, or compare scenarios whose units, coordinate conventions, catalog selection, and model assumptions are known.
- RMS (s)
- Required number in s. Travel-time RMS residual.
- v (km/s)
- Optional number in km/s. Representative phase speed.
- N
- Required integer. Number of readings.
The cited overview of Seismology supplies background for the terminology and domain context used by this tool.1
How Location Formal Error Scale Factor works
Heuristic horizontal formal error: σ_h ≈ RMS·v_p·√(N/(N−4)). Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.
- σ_h (km)
- Returned number in km. Scaled horizontal formal error.
- Good?
- Returned boolean. Whether the error is under 2 km.
Limitations and assumptions
- Earth structure, source geometry, path effects, site response, instrument response, catalog completeness, uncertainty, and the fitted range can dominate the accuracy of simplified seismic calculations.
- RMS must be at least 0.
- v must be at least 0.
- N must be at least 1.
- Use finite inputs in the displayed units, preserve source measurements and assumptions, and independently verify consequential decisions.
Alternative or Complementary approaches
For analysis or hazard decisions, retain uncertainty and provenance and compare the result with waveform processing, calibrated regional models, and guidance from qualified seismologists or the responsible agency.
References
-
Seismology — Wikipedia contributors
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