... We demonstrate through numerical simulations that model parameters estimated with our technique are essentially bias-free, even when the average number of counts per bin is 1. ... The IW technique avoids such biases by estimating through successive iterations, where for each iteration, j, , and the best-fit parameters are determined by minimization of . ... In our sample, we find that the minimum values and best-fit parameters converge after about 6 iterations. ...

Next: Simulations Up: Maximum Likelihood Estimation of Previous: Introduction . The properties of an ensemble of faint galaxies can be defined by the distribution of the parameters of the models that best fit each individual object. ... The model also includes instrumental parameters, such as the sky background (estimated locally) and amplitude of the noise. ... The probability of the observed value is then computed for each pixel using the adopted error distribution. ...

... In brief: the frequency-dependent radiative transfer equation is solved for a dust under assumption of spherically-symmetric geometry for its distribution taking into account particle size distribution and quantum heating effects for the very small dust particles. ... Table: Model parameters for IRAS04296+3429. ... parameter . ... hot dust shell) . ... The best fit to the spectral energy distribution of IRAS04296 is shown by heavy solid line (see Table2 for details concerning parameters of the model...

... A number of different statistical methods are used for estimating parameters from a data set. The most commonly used one is the least squares method which estimates a parameter by minimizing the function : . where y is the dependent and x the independent variables while f is a given function. ... The most important assumptions are that the errors in the dependent variable are normal distributed, the variance is homogeneous, and the independent variables have no errors and are uncorrelated. ...

Scale-heights of the Galactic disk subsytems with different ages and metallicities . V.Marsakov & Yu. ... It is based on the fact, that all stars cross the disk plane several times during their Galactic orbital period. ... We have used our representative sample of nearby disk F2-G2 stars Marsakov & Shevelev (1995) in which fundamental stellar parameters was determined on the basis of published date on uvby-photometry, proper motion and radial velocities. ... Marsakov V.A., Shevelev Yu.G. Bull. ...

... St Petersburg 23, September 2014 1 Motivation · Origin of Martian moons? ... Considered error sources: ­ Phobos a priori ephemerides; ­ Phobos a priori GM value; ­ measurements noise; ­ different strategies; · Methods: ­ real data analysis; ­ simulations. ... St Petersburg 23, September 2014 8 Simulations: sensitivity of the measurements to the a priori GM value Simulations: zero noise+ IMCCE a priori ephemerides +GMPH = 7.16 * 105 m3/sec2. ... St Petersburg 23, September 2014 14 Thank you! ...

... This thread illustrates a step-by-step recipe to perform EPIC sources detection. ... However, some users - in particular SAS novices - may find useful to perform each individual step of the source detection algorithm, to achieve a better control and understanding of its outcomes. ... The event list MOS.evt is assumed to have been already cleaned for high-background intervals, following, e.g. , steps 3. to 5. in the edetect_chain thread . ... An example of MOS background map is shown in Fig.3. ...

... RJMCMC Similar to Richardson Green 1997 Knowledge of the PSF makes things easier Insensitive to e.g. posterior for ten sources with = 3: Number of Components 9 10 11 12 0.141 0.222 0.220 0.157 0.022 0.029 0.027 0.021 Mean SD 7 0.029 0.018 8 0.058 0.019 13 0.082 0.014 Simulated Data Source region (2 SD) is about 28% of the area and contains about 41% of the observations Positions (-2, 0), (0, 1), (1.5, 0) with intensities ... Approximate the number of sources (2 in this case) 2. ...

... Fitting the observed dependence includes calculations of the polarization cross-sections averaged over particles orientation and size distribution, their normalization and the comparison of obtained dependencies with Serkowski's curve representing observational data for a chosen star. ... Variations of the polarization factors with wavelength are shown in Fig. 16 for homogeneous spheroidal particles with PF orientation. ... The distinction between prolate and oblate spheroids is also clearly seen. ...