# A nonparametric method to assess significance of events in search for gravitational waves with false discovery rate

## TL;DR

This paper introduces a nonparametric, assumption-free method to evaluate the significance of gravitational wave events using false discovery rate, providing a more straightforward alternative to existing techniques.

## Contribution

It proposes a novel non-parametric approach to estimate p-values and assess event significance via q-values, differing from traditional methods like P_astro in gravitational wave analysis.

## Key findings

- Consistent significance assessment for most known events.
- Differences found in significance for some marginal events.
- Method applicable to other gravitational wave searches.

## Abstract

In this paper, we present a consistent procedure to assess the significance of gravitational wave events observed by laser interferometric gravitational wave detectors based on the background distribution of detection statistic. We propose a non-parametric method to estimate $p$-value. Based on the estimated $p$-values, we propose a new procedure to assess the significance of a particular event with $q$-value which is the minimum false discovery rate that can be attained when calling the event significant. The $q$-value gives us a criterion on the significance of events which is different from $P_{\rm astro}$ which is used in the LIGO-Virgo analysis and in other analysis. The proposed procedure is applied to the 1-OGC and 2-OGC catalogs [2][3]. For most of the events which were claimed significant in [2] and [3], we also obtain the same results. However, there are differences in the significance for several marginal events. Since the proposed procedure does not require any assumptions on signal and noise, it is very simple and straightforward. The procedure is also applicable to other searches for gravitational waves whose background distribution of detection statistic is difficult to know.