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M Icazalizaola - One of the best experts on this subject based on the ideXlab platform.

  • the clustering of the sdss iv extended baryon oscillation spectroscopic survey dr14 lrg Sample Structure growth rate measurement from the anisotropic lrg correlation function in the redshift range 0 6 z 1 0
    Monthly Notices of the Royal Astronomical Society, 2020
    Co-Authors: M Icazalizaola, Mariana Vargasmagana, S Fromenteau, Shadab Alam, B Camacho, Hector Gilmarin, Romain Paviot, Ashley J Ross, Donald P Schneider
    Abstract:

    We analyze the anisotropic clustering of the Sloan Digital Sky Survey-IV Extended Baryon Oscillation Spectroscopic Survey (eBOSS) Luminous Red Galaxy Data Release 14 (DR14) Sample combined with Baryon Oscillation Spectroscopic Survey (BOSS) CMASS Sample of galaxies in the redshift range 0.6$Sample. The eBOSS-CMASS Luminous Red Galaxy Sample has a sky coverage of 1,844 deg$^2$, with an effective volume of 0.9 Gpc$^3$. The analysis was made in configuration space using a Legendre multipole expansion. The Redshift Space Distortion signal is modeled as a combination of the Convolution Lagrangian Perturbation Model and the Gaussian Streaming Model. We constrain the logarithmic growth of Structure times the amplitude of dark matter density fluctuations, $f (z_{\rm eff})\sigma_8(z_{\rm eff})=0.454 \pm0.139 $, and the Alcock-Paczynski dilation scales which constraints the angular diameter distance $D_A(z_{eff})=1466.5 \pm 136.6 (r_s/r_s^{\rm fid})$ and $H(z_{\rm eff})=105.8 \pm 16 (r_s^{\rm fid}/r_s) \mathrm{km\,s^{-1}\,Mpc^{-1}}$, where $r_s$ is the sound horizon at the end of the baryon drag epoch and $r_s^{\rm fid}$ is its value in the fiducial cosmology at an effective redshift $z_{\rm eff}=0.72$. These results are in full agreement with the current $\Lambda$-Cold Dark Matter ($\Lambda$-CDM) cosmological model inferred from Planck measurements. This study is the first eBOSS LRG full-shape analysis i.e. including Redshift-Space Distortions (RSD) simultaneously with the Alcock-Paczynski (AP) effect and the Baryon Acoustic Oscillation (BAO) scale.

  • the clustering of the sdss iv extended baryon oscillation spectroscopic survey dr14 lrg Sample Structure growth rate measurement from the anisotropic lrg correlation function in the redshift range 0 6 z 1 0
    Monthly Notices of the Royal Astronomical Society, 2020
    Co-Authors: M Icazalizaola, Mariana Vargasmagana, S Fromenteau, Shadab Alam, B Camacho, Hector Gilmarin, Romain Paviot, Ashley J Ross, Donald P Schneider
    Abstract:

    We analyze the anisotropic clustering of the Sloan Digital Sky Survey-IV Extended Baryon Oscillation Spectroscopic Survey (eBOSS) Luminous Red Galaxy Data Release 14 (DR14) Sample combined with Baryon Oscillation Spectroscopic Survey (BOSS) CMASS Sample of galaxies in the redshift range 0.6$Sample. The eBOSS-CMASS Luminous Red Galaxy Sample has a sky coverage of 1,844 deg$^2$, with an effective volume of 0.9 Gpc$^3$. The analysis was made in configuration space using a Legendre multipole expansion. The Redshift Space Distortion signal is modeled as a combination of the Convolution Lagrangian Perturbation Model and the Gaussian Streaming Model. We constrain the logarithmic growth of Structure times the amplitude of dark matter density fluctuations, $f (z_{\rm eff})\sigma_8(z_{\rm eff})=0.454 \pm0.139 $, and the Alcock-Paczynski dilation scales which constraints the angular diameter distance $D_A(z_{eff})=1466.5 \pm 136.6 (r_s/r_s^{\rm fid})$ and $H(z_{\rm eff})=105.8 \pm 16 (r_s^{\rm fid}/r_s) \mathrm{km\,s^{-1}\,Mpc^{-1}}$, where $r_s$ is the sound horizon at the end of the baryon drag epoch and $r_s^{\rm fid}$ is its value in the fiducial cosmology at an effective redshift $z_{\rm eff}=0.72$. These results are in full agreement with the current $\Lambda$-Cold Dark Matter ($\Lambda$-CDM) cosmological model inferred from Planck measurements. This study is the first eBOSS LRG full-shape analysis i.e. including Redshift-Space Distortions (RSD) simultaneously with the Alcock-Paczynski (AP) effect and the Baryon Acoustic Oscillation (BAO) scale.

Hector Gilmarin - One of the best experts on this subject based on the ideXlab platform.

  • the clustering of the sdss iv extended baryon oscillation spectroscopic survey dr14 lrg Sample Structure growth rate measurement from the anisotropic lrg correlation function in the redshift range 0 6 z 1 0
    Monthly Notices of the Royal Astronomical Society, 2020
    Co-Authors: M Icazalizaola, Mariana Vargasmagana, S Fromenteau, Shadab Alam, B Camacho, Hector Gilmarin, Romain Paviot, Ashley J Ross, Donald P Schneider
    Abstract:

    We analyze the anisotropic clustering of the Sloan Digital Sky Survey-IV Extended Baryon Oscillation Spectroscopic Survey (eBOSS) Luminous Red Galaxy Data Release 14 (DR14) Sample combined with Baryon Oscillation Spectroscopic Survey (BOSS) CMASS Sample of galaxies in the redshift range 0.6$Sample. The eBOSS-CMASS Luminous Red Galaxy Sample has a sky coverage of 1,844 deg$^2$, with an effective volume of 0.9 Gpc$^3$. The analysis was made in configuration space using a Legendre multipole expansion. The Redshift Space Distortion signal is modeled as a combination of the Convolution Lagrangian Perturbation Model and the Gaussian Streaming Model. We constrain the logarithmic growth of Structure times the amplitude of dark matter density fluctuations, $f (z_{\rm eff})\sigma_8(z_{\rm eff})=0.454 \pm0.139 $, and the Alcock-Paczynski dilation scales which constraints the angular diameter distance $D_A(z_{eff})=1466.5 \pm 136.6 (r_s/r_s^{\rm fid})$ and $H(z_{\rm eff})=105.8 \pm 16 (r_s^{\rm fid}/r_s) \mathrm{km\,s^{-1}\,Mpc^{-1}}$, where $r_s$ is the sound horizon at the end of the baryon drag epoch and $r_s^{\rm fid}$ is its value in the fiducial cosmology at an effective redshift $z_{\rm eff}=0.72$. These results are in full agreement with the current $\Lambda$-Cold Dark Matter ($\Lambda$-CDM) cosmological model inferred from Planck measurements. This study is the first eBOSS LRG full-shape analysis i.e. including Redshift-Space Distortions (RSD) simultaneously with the Alcock-Paczynski (AP) effect and the Baryon Acoustic Oscillation (BAO) scale.

  • the clustering of the sdss iv extended baryon oscillation spectroscopic survey dr14 lrg Sample Structure growth rate measurement from the anisotropic lrg correlation function in the redshift range 0 6 z 1 0
    Monthly Notices of the Royal Astronomical Society, 2020
    Co-Authors: M Icazalizaola, Mariana Vargasmagana, S Fromenteau, Shadab Alam, B Camacho, Hector Gilmarin, Romain Paviot, Ashley J Ross, Donald P Schneider
    Abstract:

    We analyze the anisotropic clustering of the Sloan Digital Sky Survey-IV Extended Baryon Oscillation Spectroscopic Survey (eBOSS) Luminous Red Galaxy Data Release 14 (DR14) Sample combined with Baryon Oscillation Spectroscopic Survey (BOSS) CMASS Sample of galaxies in the redshift range 0.6$Sample. The eBOSS-CMASS Luminous Red Galaxy Sample has a sky coverage of 1,844 deg$^2$, with an effective volume of 0.9 Gpc$^3$. The analysis was made in configuration space using a Legendre multipole expansion. The Redshift Space Distortion signal is modeled as a combination of the Convolution Lagrangian Perturbation Model and the Gaussian Streaming Model. We constrain the logarithmic growth of Structure times the amplitude of dark matter density fluctuations, $f (z_{\rm eff})\sigma_8(z_{\rm eff})=0.454 \pm0.139 $, and the Alcock-Paczynski dilation scales which constraints the angular diameter distance $D_A(z_{eff})=1466.5 \pm 136.6 (r_s/r_s^{\rm fid})$ and $H(z_{\rm eff})=105.8 \pm 16 (r_s^{\rm fid}/r_s) \mathrm{km\,s^{-1}\,Mpc^{-1}}$, where $r_s$ is the sound horizon at the end of the baryon drag epoch and $r_s^{\rm fid}$ is its value in the fiducial cosmology at an effective redshift $z_{\rm eff}=0.72$. These results are in full agreement with the current $\Lambda$-Cold Dark Matter ($\Lambda$-CDM) cosmological model inferred from Planck measurements. This study is the first eBOSS LRG full-shape analysis i.e. including Redshift-Space Distortions (RSD) simultaneously with the Alcock-Paczynski (AP) effect and the Baryon Acoustic Oscillation (BAO) scale.

  • the clustering of the sdss iv extended baryon oscillation spectroscopic survey dr14 quasar Sample Structure growth rate measurement from the anisotropic quasar power spectrum in the redshift range 0 8 z 2 2
    Monthly Notices of the Royal Astronomical Society, 2018
    Co-Authors: Hector Gilmarin, Ashley J Ross, J Guy, Pauline Zarrouk, Etienne Burtin, Chiahsun Chuang, Will J Percival, Rossana Ruggeri
    Abstract:

    Author(s): Gil-Marin, H; Guy, J; Zarrouk, P; Burtin, E; Chuang, CH; Percival, WJ; Ross, AJ; Ruggeri, R; Tojerio, R; Zhao, GB; Wang, Y; Bautista, J; Hou, J; Sanchez, AG; Pâris, I; Baumgarten, F; Brownstein, JR; Dawson, KS; Eftekharzadeh, S; Gonzalez-Perez, V; Habib, S; Heitmann, K; Myers, AD; Rossi, G; Schneider, DP; Seo, HJ; Tinker, JL; Zhao, C | Abstract: © 2017 The Authors. We analyse the clustering of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey Data Release 14 quasar Sample (DR14Q).We measure the redshift space distortions using the power-spectrum monopole, quadrupole, and hexadecapole inferred from 148 659 quasars between redshifts 0.8 and 2.2, covering a total sky footprint of 2112.9 deg2. We constrain the logarithmic growth of Structure times the amplitude of dark matter density fluctuations, fσ8, and the Alcock-Paczynski dilation scales that allow constraints to be placed on the angular diameter distance DA(z) and the Hubble H(z) parameter. At the effective redshift of zeff = 1.52, fσ8(zeff) = 0.420 ± 0.076, H(zeff) = [162 ± 12] (r sfid/rs) kms-1 Mpc-1, and DA(zeff) = [1.85 ± 0.11] × 103 (rs/r sfid) Mpc, where rs is the comoving sound horizon at the baryon drag epoch and the superscript 'fid' stands for its fiducial value. The errors take into account the full error budget, including systematics and statistical contributions. These results are in full agreement with the current Λ-Cold Dark Matter cosmological model inferred from Planck measurements. Finally, we compare our measurements with other eBOSS companion papers and find excellent agreement, demonstrating the consistency and complementarity of the different methods used for analysing the data.

Donald P Schneider - One of the best experts on this subject based on the ideXlab platform.

  • the clustering of the sdss iv extended baryon oscillation spectroscopic survey dr14 lrg Sample Structure growth rate measurement from the anisotropic lrg correlation function in the redshift range 0 6 z 1 0
    Monthly Notices of the Royal Astronomical Society, 2020
    Co-Authors: M Icazalizaola, Mariana Vargasmagana, S Fromenteau, Shadab Alam, B Camacho, Hector Gilmarin, Romain Paviot, Ashley J Ross, Donald P Schneider
    Abstract:

    We analyze the anisotropic clustering of the Sloan Digital Sky Survey-IV Extended Baryon Oscillation Spectroscopic Survey (eBOSS) Luminous Red Galaxy Data Release 14 (DR14) Sample combined with Baryon Oscillation Spectroscopic Survey (BOSS) CMASS Sample of galaxies in the redshift range 0.6$Sample. The eBOSS-CMASS Luminous Red Galaxy Sample has a sky coverage of 1,844 deg$^2$, with an effective volume of 0.9 Gpc$^3$. The analysis was made in configuration space using a Legendre multipole expansion. The Redshift Space Distortion signal is modeled as a combination of the Convolution Lagrangian Perturbation Model and the Gaussian Streaming Model. We constrain the logarithmic growth of Structure times the amplitude of dark matter density fluctuations, $f (z_{\rm eff})\sigma_8(z_{\rm eff})=0.454 \pm0.139 $, and the Alcock-Paczynski dilation scales which constraints the angular diameter distance $D_A(z_{eff})=1466.5 \pm 136.6 (r_s/r_s^{\rm fid})$ and $H(z_{\rm eff})=105.8 \pm 16 (r_s^{\rm fid}/r_s) \mathrm{km\,s^{-1}\,Mpc^{-1}}$, where $r_s$ is the sound horizon at the end of the baryon drag epoch and $r_s^{\rm fid}$ is its value in the fiducial cosmology at an effective redshift $z_{\rm eff}=0.72$. These results are in full agreement with the current $\Lambda$-Cold Dark Matter ($\Lambda$-CDM) cosmological model inferred from Planck measurements. This study is the first eBOSS LRG full-shape analysis i.e. including Redshift-Space Distortions (RSD) simultaneously with the Alcock-Paczynski (AP) effect and the Baryon Acoustic Oscillation (BAO) scale.

  • the clustering of the sdss iv extended baryon oscillation spectroscopic survey dr14 lrg Sample Structure growth rate measurement from the anisotropic lrg correlation function in the redshift range 0 6 z 1 0
    Monthly Notices of the Royal Astronomical Society, 2020
    Co-Authors: M Icazalizaola, Mariana Vargasmagana, S Fromenteau, Shadab Alam, B Camacho, Hector Gilmarin, Romain Paviot, Ashley J Ross, Donald P Schneider
    Abstract:

    We analyze the anisotropic clustering of the Sloan Digital Sky Survey-IV Extended Baryon Oscillation Spectroscopic Survey (eBOSS) Luminous Red Galaxy Data Release 14 (DR14) Sample combined with Baryon Oscillation Spectroscopic Survey (BOSS) CMASS Sample of galaxies in the redshift range 0.6$Sample. The eBOSS-CMASS Luminous Red Galaxy Sample has a sky coverage of 1,844 deg$^2$, with an effective volume of 0.9 Gpc$^3$. The analysis was made in configuration space using a Legendre multipole expansion. The Redshift Space Distortion signal is modeled as a combination of the Convolution Lagrangian Perturbation Model and the Gaussian Streaming Model. We constrain the logarithmic growth of Structure times the amplitude of dark matter density fluctuations, $f (z_{\rm eff})\sigma_8(z_{\rm eff})=0.454 \pm0.139 $, and the Alcock-Paczynski dilation scales which constraints the angular diameter distance $D_A(z_{eff})=1466.5 \pm 136.6 (r_s/r_s^{\rm fid})$ and $H(z_{\rm eff})=105.8 \pm 16 (r_s^{\rm fid}/r_s) \mathrm{km\,s^{-1}\,Mpc^{-1}}$, where $r_s$ is the sound horizon at the end of the baryon drag epoch and $r_s^{\rm fid}$ is its value in the fiducial cosmology at an effective redshift $z_{\rm eff}=0.72$. These results are in full agreement with the current $\Lambda$-Cold Dark Matter ($\Lambda$-CDM) cosmological model inferred from Planck measurements. This study is the first eBOSS LRG full-shape analysis i.e. including Redshift-Space Distortions (RSD) simultaneously with the Alcock-Paczynski (AP) effect and the Baryon Acoustic Oscillation (BAO) scale.

Ashley J Ross - One of the best experts on this subject based on the ideXlab platform.

  • the clustering of the sdss iv extended baryon oscillation spectroscopic survey dr14 lrg Sample Structure growth rate measurement from the anisotropic lrg correlation function in the redshift range 0 6 z 1 0
    Monthly Notices of the Royal Astronomical Society, 2020
    Co-Authors: M Icazalizaola, Mariana Vargasmagana, S Fromenteau, Shadab Alam, B Camacho, Hector Gilmarin, Romain Paviot, Ashley J Ross, Donald P Schneider
    Abstract:

    We analyze the anisotropic clustering of the Sloan Digital Sky Survey-IV Extended Baryon Oscillation Spectroscopic Survey (eBOSS) Luminous Red Galaxy Data Release 14 (DR14) Sample combined with Baryon Oscillation Spectroscopic Survey (BOSS) CMASS Sample of galaxies in the redshift range 0.6$Sample. The eBOSS-CMASS Luminous Red Galaxy Sample has a sky coverage of 1,844 deg$^2$, with an effective volume of 0.9 Gpc$^3$. The analysis was made in configuration space using a Legendre multipole expansion. The Redshift Space Distortion signal is modeled as a combination of the Convolution Lagrangian Perturbation Model and the Gaussian Streaming Model. We constrain the logarithmic growth of Structure times the amplitude of dark matter density fluctuations, $f (z_{\rm eff})\sigma_8(z_{\rm eff})=0.454 \pm0.139 $, and the Alcock-Paczynski dilation scales which constraints the angular diameter distance $D_A(z_{eff})=1466.5 \pm 136.6 (r_s/r_s^{\rm fid})$ and $H(z_{\rm eff})=105.8 \pm 16 (r_s^{\rm fid}/r_s) \mathrm{km\,s^{-1}\,Mpc^{-1}}$, where $r_s$ is the sound horizon at the end of the baryon drag epoch and $r_s^{\rm fid}$ is its value in the fiducial cosmology at an effective redshift $z_{\rm eff}=0.72$. These results are in full agreement with the current $\Lambda$-Cold Dark Matter ($\Lambda$-CDM) cosmological model inferred from Planck measurements. This study is the first eBOSS LRG full-shape analysis i.e. including Redshift-Space Distortions (RSD) simultaneously with the Alcock-Paczynski (AP) effect and the Baryon Acoustic Oscillation (BAO) scale.

  • the clustering of the sdss iv extended baryon oscillation spectroscopic survey dr14 lrg Sample Structure growth rate measurement from the anisotropic lrg correlation function in the redshift range 0 6 z 1 0
    Monthly Notices of the Royal Astronomical Society, 2020
    Co-Authors: M Icazalizaola, Mariana Vargasmagana, S Fromenteau, Shadab Alam, B Camacho, Hector Gilmarin, Romain Paviot, Ashley J Ross, Donald P Schneider
    Abstract:

    We analyze the anisotropic clustering of the Sloan Digital Sky Survey-IV Extended Baryon Oscillation Spectroscopic Survey (eBOSS) Luminous Red Galaxy Data Release 14 (DR14) Sample combined with Baryon Oscillation Spectroscopic Survey (BOSS) CMASS Sample of galaxies in the redshift range 0.6$Sample. The eBOSS-CMASS Luminous Red Galaxy Sample has a sky coverage of 1,844 deg$^2$, with an effective volume of 0.9 Gpc$^3$. The analysis was made in configuration space using a Legendre multipole expansion. The Redshift Space Distortion signal is modeled as a combination of the Convolution Lagrangian Perturbation Model and the Gaussian Streaming Model. We constrain the logarithmic growth of Structure times the amplitude of dark matter density fluctuations, $f (z_{\rm eff})\sigma_8(z_{\rm eff})=0.454 \pm0.139 $, and the Alcock-Paczynski dilation scales which constraints the angular diameter distance $D_A(z_{eff})=1466.5 \pm 136.6 (r_s/r_s^{\rm fid})$ and $H(z_{\rm eff})=105.8 \pm 16 (r_s^{\rm fid}/r_s) \mathrm{km\,s^{-1}\,Mpc^{-1}}$, where $r_s$ is the sound horizon at the end of the baryon drag epoch and $r_s^{\rm fid}$ is its value in the fiducial cosmology at an effective redshift $z_{\rm eff}=0.72$. These results are in full agreement with the current $\Lambda$-Cold Dark Matter ($\Lambda$-CDM) cosmological model inferred from Planck measurements. This study is the first eBOSS LRG full-shape analysis i.e. including Redshift-Space Distortions (RSD) simultaneously with the Alcock-Paczynski (AP) effect and the Baryon Acoustic Oscillation (BAO) scale.

  • the clustering of the sdss iv extended baryon oscillation spectroscopic survey dr14 quasar Sample Structure growth rate measurement from the anisotropic quasar power spectrum in the redshift range 0 8 z 2 2
    Monthly Notices of the Royal Astronomical Society, 2018
    Co-Authors: Hector Gilmarin, Ashley J Ross, J Guy, Pauline Zarrouk, Etienne Burtin, Chiahsun Chuang, Will J Percival, Rossana Ruggeri
    Abstract:

    Author(s): Gil-Marin, H; Guy, J; Zarrouk, P; Burtin, E; Chuang, CH; Percival, WJ; Ross, AJ; Ruggeri, R; Tojerio, R; Zhao, GB; Wang, Y; Bautista, J; Hou, J; Sanchez, AG; Pâris, I; Baumgarten, F; Brownstein, JR; Dawson, KS; Eftekharzadeh, S; Gonzalez-Perez, V; Habib, S; Heitmann, K; Myers, AD; Rossi, G; Schneider, DP; Seo, HJ; Tinker, JL; Zhao, C | Abstract: © 2017 The Authors. We analyse the clustering of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey Data Release 14 quasar Sample (DR14Q).We measure the redshift space distortions using the power-spectrum monopole, quadrupole, and hexadecapole inferred from 148 659 quasars between redshifts 0.8 and 2.2, covering a total sky footprint of 2112.9 deg2. We constrain the logarithmic growth of Structure times the amplitude of dark matter density fluctuations, fσ8, and the Alcock-Paczynski dilation scales that allow constraints to be placed on the angular diameter distance DA(z) and the Hubble H(z) parameter. At the effective redshift of zeff = 1.52, fσ8(zeff) = 0.420 ± 0.076, H(zeff) = [162 ± 12] (r sfid/rs) kms-1 Mpc-1, and DA(zeff) = [1.85 ± 0.11] × 103 (rs/r sfid) Mpc, where rs is the comoving sound horizon at the baryon drag epoch and the superscript 'fid' stands for its fiducial value. The errors take into account the full error budget, including systematics and statistical contributions. These results are in full agreement with the current Λ-Cold Dark Matter cosmological model inferred from Planck measurements. Finally, we compare our measurements with other eBOSS companion papers and find excellent agreement, demonstrating the consistency and complementarity of the different methods used for analysing the data.

Eleazar Eskin - One of the best experts on this subject based on the ideXlab platform.

  • variance component model to account for Sample Structure in genome wide association studies
    Nature Genetics, 2010
    Co-Authors: Hyun Min Kang, Jae Hoon Sul, Noah Zaitlen, Sit Yee Kong, Nelson B Freimer, Chiara Sabatti, Eleazar Eskin
    Abstract:

    Although genome-wide association studies (GWASs) have identified numerous loci associated with complex traits, imprecise modeling of the genetic relatedness within study Samples may cause substantial inflation of test statistics and possibly spurious associations. Variance component approaches, such as efficient mixed-model association (EMMA), can correct for a wide range of Sample Structures by explicitly accounting for pairwise relatedness between individuals, using high-density markers to model the phenotype distribution; but such approaches are computationally impractical. We report here a variance component approach implemented in publicly available software, EMMA eXpedited (EMMAX), that reduces the computational time for analyzing large GWAS data sets from years to hours. We apply this method to two human GWAS data sets, performing association analysis for ten quantitative traits from the Northern Finland Birth Cohort and seven common diseases from the Wellcome Trust Case Control Consortium. We find that EMMAX outperforms both principal component analysis and genomic control in correcting for Sample Structure.

  • Variance component model to account for Sample Structure in genome-wide association studies
    Nature genetics, 2010
    Co-Authors: Hyun Min Kang, Jae Hoon Sul, Noah Zaitlen, Sit Yee Kong, Nelson B Freimer, Chiara Sabatti, Eleazar Eskin
    Abstract:

    Although genome-wide association studies (GWASs) have identified numerous loci associated with complex traits, imprecise modeling of the genetic relatedness within study Samples may cause substantial inflation of test statistics and possibly spurious associations. Variance component approaches, such as efficient mixed-model association (EMMA), can correct for a wide range of Sample Structures by explicitly accounting for pairwise relatedness between individuals, using high-density markers to model the phenotype distribution; but such approaches are computationally impractical. We report here a variance component approach implemented in publicly available software, EMMA eXpedited (EMMAX), that reduces the computational time for analyzing large GWAS data sets from years to hours. We apply this method to two human GWAS data sets, performing association analysis for ten quantitative traits from the Northern Finland Birth Cohort and seven common diseases from the Wellcome Trust Case Control Consortium. We find that EMMAX outperforms both principal component analysis and genomic control in correcting for Sample Structure.

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