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tokens: range from 9 to 12 in the H band. Fig. 2. Luminosity distribution function in the H band for the APOGEE – LAMOST stellar catalog. The catalog covers a broad magnitude range from 7 to almost 14 mag. Most of the stars are in the magnitude range from 9 to 12 in the H band. 2.2. Signal-to-noise ratio APOGEE aims to obtain high-resolution H -band spectra with high S/N (100 per half-resolution element of pixels) for stars in the bulge, disk, and halo of the Milky Way ( Zasowski et al. 2013 , 2017 ). Most APOGEE targets are observed in several visits. After multiple visits, a combined spectrum is produced ( Nidever et al. 2015 ). LAMOST DR3 provides the S/N per pixel for the targets as calculated in five different bands, u , g , r , i and z . Using the center wavelength and bandwidth, they obtain the wavelength range for each SDSS band, and then the S/N in each band is the median value at each pixel in this band ( Luo et al. 2015 ). The cumulative histograms of S/N in APOGEE and in LAMOST for the z band (left panel in Fig. 3 ) shows that the APOGEE survey has 80% of stars in common with S / N > 100, and 40% with S / N > 200. The LAMOST survey has 40% of stars in common with S / N > 100, and 10% with S / N > 200 2 . The right panel in Fig. 3 shows the S/N from APOGEE and LAMOST spectra for the common stellar catalog as a function of the H -band magnitude from the 2MASS survey ( Skrutskie et al. 2006 ). This figure shows a clear relation between magnitude and S/N in APOGEE. This relation is weaker in LAMOST DR3 data and the H band, where a given stellar magnitude has a wide range in S/N. Fig. 3. Left panel : cumulative histograms of S/N per half-resolution element (approximately a pixel) for APOGEE (solid line) and S/N per pixel for LAMOST (dashed line), as provided from the original catalogs. Right panels : S/N from APOGEE and LAMOST spectra for the common objects as a function of the H -band magnitude from the 2MASS survey. 2.3. Radial velocities In APOGEE DR14 ( Abolfathi et al. 2018 ), RVs are determined for each individual visit to identify stars with companion-induced Doppler shifts. The individual visit spectra are resampled and combined to generate a single spectrum for each object. Final RVs are obtained by cross-correlation against a grid of synthetic spectra spanning a wide range of stellar parameters. The APOGEE instrument and the existing RV software routinely deliver RVs per visit at a precision of ∼0.07 km s −1 for S / N > 20, while the survey provides external calibration sufficient to ensure accuracies at the level of ∼0.35 km s −1 . RVs in APOGEE are reported with respect to the center of mass (barycenter) of the solar system ( Nidever et al. 2015 ). The LAMOST 1D pipeline ( Luo et al. 2015 ) also measures the RVs using a cross-correlation method. The pipeline recognizes the stellar spectral classes and simultaneously determines the RVs from the best-fit correlation function between the observed spectra and the template. The RVs are