Friday, May 20, 2005

GravStat 2005: Shawhan

GW transients: upper limits and discoveries. Waveforms may be known or unknown. Known depends on one or more physical parameters. Physically identical signals may have different source origins. Given source classes can produce different signals.

Selection of event candidates
Identify regions of interest - filter to produce a trigger. Use a low threshold then apply additional tests - waveform consistency, noise stationarity, coincidence among detectors, cross-correlation of datastreams.

Summarize the outcome - define a statistic which has some power to distinguish S+B from B eg events with S/N > some threshold.

Cleanest evidence for discovery is a p-value < some threshold. A frequentist confidence interval is a set of models for which the observed outcome was "likely". Maximum S/N ratio test (Brady et al. CQG 21, S1775, 2004).

Issues:
Do we really need to calculate a statistic - can we use all the information available.
Is there another way to talk about discovery other than the p-value.
What is appropriate background rate ?
Why do a F analysis, a B analysis,... ?

No comments: