Pre-2010

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Statistics, Handle with Care: Detecting Multiple Model Components with the Likelihood Ratio Test
Protassov, Rostislav; van Dyk, David A.; Connors, Alanna; Kashyap, Vinay L.; Siemiginowska, Aneta

The likelihood ratio test (LRT) and the related F-test, popularized in astrophysics by Eadie and coworkers in 1971, Bevington in 1969, Lampton, Margon, & Bowyer, in 1976, Cash in 1979, and Avni in 1978, do not (even asymptotically) adhere to their n …

SigSpec. I. Frequency- and phase-resolved significance in Fourier space
Reegen, P.

Context: Identifying frequencies with low signal-to-noise ratios in time series of stellar photometry and spectroscopy, and measuring their amplitude ratios and peak widths accurately, are critical goals for asteroseismology. These are also challeng …

Studies in astronomical time series analysis. II – Statistical aspects of spectral analysis of unevenly spaced data
Scargle, J. D.

Detection of a periodic signal hidden in noise is frequently a goal in astronomical data analysis. This paper does not introduce a new detection technique, but instead studies the reliability and efficiency of detection with the most commonly used t …

The quasi-periodic oscillations and very low frequency noise of Scorpius X-1 as transient chaos – A dripping handrail?
Scargle, Jeffrey D.; Steiman-Cameron, Thomas; Young, Karl; Donoho, David L.; Crutchfield, James P.; Imamura, James

We present evidence that the quasi-periodic oscillations (QPO) and very low frequency noise (VLFN) characteristic of many accretion sources are different aspects of the same physical process. We analyzed a long, high time resolution EXOSAT observati …

Studies in Astronomical Time Series Analysis. V. Bayesian Blocks, a New Method to Analyze Structure in Photon Counting Data
Scargle, Jeffrey D.

I describe a new time-domain algorithm for detecting localized structures (bursts), revealing pulse shapes, and generally characterizing intensity variations. The input is raw counting data, in any of three forms: time-tagged photon events (TTE), bi …

Statistical analysis of astronomical data containing upper bounds – General methods and examples drawn from X-ray astronomy
Schmitt, J. H. M. M.

Statistical techniques suitable for the analysis of censored data, i.e., data containing both flux measurements and upper limits, are adapted to astronomical usage from the field of survival analysis, and are used in a statistical analysis of X-ray …

On the advantage of using analysis of variance for period search
Schwarzenberg-Czerny, A.

One-way analysis of variance (AoV) is recommended as a method for detection of sharp periodic signals. Application of the method requires folding and binning data with a trial period. Among several methods of this type employed in astronomy, AoV has …

Flicker of extragalactic radio sources at two frequencies
Simonetti, J. H.; Cordes, J. M.; Heeschen, D. S.

Flicker of extragalactic sources was investigated by observing 14 flat and 20 steep spectrum sources at 1410 and 2380 MHz from the Arecibo Observatory on 20 successive days. The rms intensity variation of flat spectrum sources is, on average, higher …

Period determination using phase dispersion minimization
Stellingwerf, R. F.

We derive a period determination technique that is well suited to the case of nonsinusoidal time variation covered by only a few irregularly spaced observations. A detailed statistical analysis allows comparison with other techniques and indicates t …

Analysis of Energy Spectra with Low Photon Counts via Bayesian Posterior Simulation
van Dyk, David A.; Connors, Alanna; Kashyap, Vinay L.; Siemiginowska, Aneta

Over the past 10 years Bayesian methods have rapidly grown more popular in many scientific disciplines as several computationally intensive statistical algorithms have become feasible with increased computer power. In this paper we begin with a gene …

Estimating Dark Matter Distributions
Wang, Xiao; Woodroofe, Michael; Walker, Matthew G.; Mateo, Mario; Olszewski, Edward

Thanks to instrumental advances, new, very large kinematic data sets for nearby dwarf spheroidal (dSph) galaxies are on the horizon. A key aim of these data sets is to help determine the distribution of dark matter in these galaxies. Past analyses h …

An objective classification system for spiral galaxies. I The two dominant dimensions
Whitmore, B. C.

A large number of observational parameters for the Rubin et al. sample of 60 spiral galaxies, ranging from Sa to Sc, have been compiled. A principal component analysis carried out on this sample shows that about 85 percent of the observational varia …

The generalised Lomb-Scargle periodogram. A new formalism for the floating-mean and Keplerian periodograms
Zechmeister, M.; Kürster, M.

The Lomb-Scargle periodogram is a common tool in the frequency analysis of unequally spaced data equivalent to least-squares fitting of sine waves. We give an analytic solution for the generalisation to a full sine wave fit, including an offset and …