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J/MNRAS/414/2602    Automated classification of HIP variables    (Dubath+, 2011)

Random forest automated supervised classification of Hipparcos periodic variable stars. Dubath P., Rimoldini L., Suveges M., Blomme J., Lopez M., Sarro L.M., De Ridder J., Cuypers J., Guy L., Lecoeur I., Nienartowicz K., Jan A., Beck M., Mowlavi N., De Cat P., Lebzelter T., Eyer L. <Mon. Not. R. Astron. Soc., 414, 2602-2617 (2011)> =2011MNRAS.414.2602D
ADC_Keywords: Models ; Stars, variable ; MK spectral classification Keywords: methods: data analysis - methods: statistical - techniques: photometric - catalogues - stars: variables: general Abstract: We present an evaluation of the performance of an automated classification of the Hipparcos periodic variable stars into 26 types. The sub-sample with the most reliable variability types available in the literature is used to train supervised algorithms to characterize the type dependencies on a number of attributes. The most useful attributes evaluated with the random forest methodology include, in decreasing order of importance, the period, the amplitude, the V-I colour index, the absolute magnitude, the residual around the folded light-curve model, the magnitude distribution skewness and the amplitude of the second harmonic of the Fourier series model relative to that of the fundamental frequency. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table3.dat 110 1661 The Hipparcos training set star list with literature types and attribute values table4.dat 110 882 Results obtained for the Hipparcos stars excluded from the training set
See also: I/239 : The Hipparcos and Tycho Catalogues (ESA 1997) Byte-by-byte Description of file: table[34].dat
Bytes Format Units Label Explanations
1- 6 I6 --- HIP HIP number 8- 15 A8 --- Type Type of variable 17- 23 A7 ---- PType Predicted type (only in table4) 25- 31 F7.4 [d] logP Period extracted with the Lomb-Scargle method [Log(Period)] 33- 37 F5.2 [---] logA Amplitude of the light-curve model [Log(Amplitude)] 39- 43 F5.2 mag V-I Mean V-I colour index [V-I] 45- 50 F6.2 mag Mhip Hipparcos absolute magnitude derived from the parallaxes neglecting interstellar absorption [MHipparcos] (1) 52- 56 F5.2 --- res/raw Median absolute of the residuals (obtained by subtracting model values from the raw light curve) divided by the Median Absolute Deviation (MAD) of the raw light-curve values around the median [Scatter:res/raw] 58- 62 F5.2 --- Skew Unbiased weighted skewness of the magnitude distribution [Skewness] 64- 68 F5.2 [-] log(1+A2/A1) Amplitude ratio between the second harmonic and the fundamental (plus one, to avoid negative values) [Log(1+A2/A1)] 70- 74 F5.2 --- P2p/2P Sum of the squares of the magnitude differences between pairs of successive data points in the light curve folded around twice the period divided by the same quantity derived from the raw light curve [P2p scatter:2P/raw] 76- 80 F5.2 --- P2p Median of the absolute values of the differences between successive magnitudes in the raw light curve normalized by the MAD around the median [P2p_scatter] 82- 86 F5.2 --- P90 The 90th percentile of the absolute residual values around the 2P model divided by the same quantity for the residuals around the P model. The 2P model is a model recomputed using twice the period value [Percentile90:2P/P] 88- 92 F5.2 % Res Mean of the squared residuals around the model [Residual_scatter] 94- 98 F5.2 rad Phase2 Phase of the second harmonic after setting the phase of the fundamental to zero [Phase2] (2) 100-104 F5.2 --- P2P/P Median of the absolute values of the differences between successive magnitudes in the folded light curve normalized by the MAD around the median of the raw light curve [P2p_scatter:P/raw] 106-110 F5.2 --- Slope Sum of the square of the slopes of lines joining the data points before and after a number of selected outliers towards faint magnitude (e.g., data points during eclipses) [P2p_slope] (3)
Note (1): Because of measurement uncertainties, some stars have negative parallax values. Each of these values is replaced by a positive value taken randomly from a Gaussian distribution with zero mean and a standard deviation equal to the measurement uncertainty. In many cases, the derived absolute magnitudes represent lower limits as the parallax measurements are not significant. Note (2): by an appropriate transformation Phase2=arctan(sin(φ2-2φ1),cos(φ2-2φ1)) (Debosscher et al., 2007, Cat. J/A+A/475/1159). Note (3): This is set to zero if there are no such outliers in the light curve.
History: From electronic version of the journal
(End) Patricia Vannier [CDS] 17-Feb-2012
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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