Using the F test to analize AGNs short period variability

ZIBECHI, L.; ANDRUCHOW, I.; CELLONE, S. A.; ROMERO, GUSTAVO E; COMBI, J. A.

Congreso; Reunion Anual de la Asociacion Argentina de Astronomia; 2011

We undertake here a re-analysis of variability results for a sample of active galactic nuclei (AGNs) that were presented in Zibecchi et al. (2011, BAAA, 54, 325). In this work we study the application of the F statistics, which is based on the ratio of variances. The motivation for this re-analysis is that some authors have begun to use this statistics during the last years, but there is still no thorough comparison between the different tests and their respective advantages or disadvantages. We found that, in some cases, the formal state of variability depends on the test used. We thus made a comparison of the results obtained by applying different statistics in order to decide which of them is the most efficient and reliable.