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John E Ware - One of the best experts on this subject based on the ideXlab platform.
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evaluation of the mos sf 36 physical functioning scale pf 40 ii comparison of Relative Precision using likert and rasch scoring methods
Journal of Clinical Epidemiology, 1997Co-Authors: Colleen A Mchorney, Stephen M Haley, John E WareAbstract:This study examined the Relative Precision (RP) of two methods of scoring the 10-item Physical Functioning Scale (PF-10) from a large sample of patients (n = 3445) of the Medical Outcomes Study. Based on a Likert scaling model, the PF-10 summated scoring method was compared with a Rasch Item Response Theory (IRT) scaling model in which raw scores were transformed into a latent trait variable of physical functioning. Potential differences between scoring methods were hypothesized to be attributed to: (1) the logarithmic nature of the Rasch transformation; (2) the unevenness of the PF-10 item distributions; and (3) reduction of within-group variance. RP ratios favored the Rasch model in discriminating between patients who differed in disease severity. The Rasch and Likert scoring models performed similarly for tests involving sensitivity to change over a two-year follow-up period. In all comparisons, differences between methods were most apparent in clinical groups whose scores most approximated the extremes of the score distribution. Further research is necessary to test for differences between scoring models in discrimination and sensitivity to change among clinical groups whose scores are sufficiently spread across the continuum of physical functioning, in particular patients with either very high or low physical functioning. The Rasch model of scoring may have important implications for the clinical interpretation of individual scores at all ranges of the scale.
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evaluation of the mos sf 36 physical functioning scale pf 10 ii comparison of Relative Precision using likert and rasch scoring methods
Journal of Clinical Epidemiology, 1997Co-Authors: Colleen A Mchorney, Stephen M Haley, John E WareAbstract:This study examined the Relative Precision (RP) of two methods of scoring the 10-item Physical Functioning Scale (PF-10) from a large sample of patients (n = 3445) of the Medical Outcomes Study. Based on a Likert scaling model, the PF-10 summated scoring method was compared with a Rasch Item Response Theory (IRT) scaling model in which raw scores were transformed into a latent trait variable of physical functioning. Potential differences between scoring methods were hypothesized to be attributed to: (1) the logarithmic nature of the Rasch transformation; (2) the unevenness of the PF-10 item distributions; and (3) reduction of within-group variance. RP ratios favored the Rasch model in discriminating between patients who differed in disease severity. The Rasch and Likert scoring models performed similarly for tests involving sensitivity to change over a two-year follow-up period. In all comparisons, differences between methods were most apparent in clinical groups whose scores most approximated the extremes of the score distribution. Further research is necessary to test for differences between scoring models in discrimination and sensitivity to change among clinical groups whose scores are sufficiently spread across the continuum of physical functioning, in particular patients with either very high or low physical functioning. The Rasch model of scoring may have important implications for the clinical interpretation of individual scores at all ranges of the scale.
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the validity and Relative Precision of mos short and long form health status scales and dartmouth coop charts results from the medical outcomes study
Medical Care, 1992Co-Authors: Colleen A Mchorney, John E Ware, William H Rogers, Anastasia E Raczek, J Rachel F LuAbstract:This study estimated the validity and Relative Precision (RP) of four methods (MOS long- and short-form scales, global items, and COOP Poster Charts) in measuring six general health concepts. The authors also tested whether and how precisely each method discriminated Relatively well adult patients (
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the validity and Relative Precision of mos short and long form health status scales and dartmouth coop charts results from the medical outcomes study
Medical Care, 1992Co-Authors: Colleen A Mchorney, John E Ware, William H Rogers, Anastasia E RaczekAbstract:This study estimated the validity and Relative Precision (RP) of four methods (MOS long- and short-form scales, global items, and COOP Poster Charts) in measuring six general health concepts. The authors also tested whether and how precisely each method discriminated Relatively well adult patients (N = 638) from those with only severe chronic medical (N = 168) and only psychiatric conditions (N = 163), as clinically defined. For comparisons between the well group and both medical and psychiatric groups, RP estimates favored long-form over short-form, multi-item scales, and favored multi-item scales over single-item global measures and poster charts. In relation to long forms, short-form multi-item scales achieved a median RP of .93; RP estimates for global items and poster charts were .81 and .67, respectively. Variations in RP across methods and concepts were linked to differences in the coarseness of measurement scales, reliability, and content (including the effects of chart illustrations). These variations in RP have implications for the interpretation of scores, the statistical power of comparisons between clinical groups, and the size of confidence intervals around individual patient scores.
Colleen A Mchorney - One of the best experts on this subject based on the ideXlab platform.
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evaluation of the mos sf 36 physical functioning scale pf 40 ii comparison of Relative Precision using likert and rasch scoring methods
Journal of Clinical Epidemiology, 1997Co-Authors: Colleen A Mchorney, Stephen M Haley, John E WareAbstract:This study examined the Relative Precision (RP) of two methods of scoring the 10-item Physical Functioning Scale (PF-10) from a large sample of patients (n = 3445) of the Medical Outcomes Study. Based on a Likert scaling model, the PF-10 summated scoring method was compared with a Rasch Item Response Theory (IRT) scaling model in which raw scores were transformed into a latent trait variable of physical functioning. Potential differences between scoring methods were hypothesized to be attributed to: (1) the logarithmic nature of the Rasch transformation; (2) the unevenness of the PF-10 item distributions; and (3) reduction of within-group variance. RP ratios favored the Rasch model in discriminating between patients who differed in disease severity. The Rasch and Likert scoring models performed similarly for tests involving sensitivity to change over a two-year follow-up period. In all comparisons, differences between methods were most apparent in clinical groups whose scores most approximated the extremes of the score distribution. Further research is necessary to test for differences between scoring models in discrimination and sensitivity to change among clinical groups whose scores are sufficiently spread across the continuum of physical functioning, in particular patients with either very high or low physical functioning. The Rasch model of scoring may have important implications for the clinical interpretation of individual scores at all ranges of the scale.
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evaluation of the mos sf 36 physical functioning scale pf 10 ii comparison of Relative Precision using likert and rasch scoring methods
Journal of Clinical Epidemiology, 1997Co-Authors: Colleen A Mchorney, Stephen M Haley, John E WareAbstract:This study examined the Relative Precision (RP) of two methods of scoring the 10-item Physical Functioning Scale (PF-10) from a large sample of patients (n = 3445) of the Medical Outcomes Study. Based on a Likert scaling model, the PF-10 summated scoring method was compared with a Rasch Item Response Theory (IRT) scaling model in which raw scores were transformed into a latent trait variable of physical functioning. Potential differences between scoring methods were hypothesized to be attributed to: (1) the logarithmic nature of the Rasch transformation; (2) the unevenness of the PF-10 item distributions; and (3) reduction of within-group variance. RP ratios favored the Rasch model in discriminating between patients who differed in disease severity. The Rasch and Likert scoring models performed similarly for tests involving sensitivity to change over a two-year follow-up period. In all comparisons, differences between methods were most apparent in clinical groups whose scores most approximated the extremes of the score distribution. Further research is necessary to test for differences between scoring models in discrimination and sensitivity to change among clinical groups whose scores are sufficiently spread across the continuum of physical functioning, in particular patients with either very high or low physical functioning. The Rasch model of scoring may have important implications for the clinical interpretation of individual scores at all ranges of the scale.
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the validity and Relative Precision of mos short and long form health status scales and dartmouth coop charts results from the medical outcomes study
Medical Care, 1992Co-Authors: Colleen A Mchorney, John E Ware, William H Rogers, Anastasia E Raczek, J Rachel F LuAbstract:This study estimated the validity and Relative Precision (RP) of four methods (MOS long- and short-form scales, global items, and COOP Poster Charts) in measuring six general health concepts. The authors also tested whether and how precisely each method discriminated Relatively well adult patients (
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the validity and Relative Precision of mos short and long form health status scales and dartmouth coop charts results from the medical outcomes study
Medical Care, 1992Co-Authors: Colleen A Mchorney, John E Ware, William H Rogers, Anastasia E RaczekAbstract:This study estimated the validity and Relative Precision (RP) of four methods (MOS long- and short-form scales, global items, and COOP Poster Charts) in measuring six general health concepts. The authors also tested whether and how precisely each method discriminated Relatively well adult patients (N = 638) from those with only severe chronic medical (N = 168) and only psychiatric conditions (N = 163), as clinically defined. For comparisons between the well group and both medical and psychiatric groups, RP estimates favored long-form over short-form, multi-item scales, and favored multi-item scales over single-item global measures and poster charts. In relation to long forms, short-form multi-item scales achieved a median RP of .93; RP estimates for global items and poster charts were .81 and .67, respectively. Variations in RP across methods and concepts were linked to differences in the coarseness of measurement scales, reliability, and content (including the effects of chart illustrations). These variations in RP have implications for the interpretation of scores, the statistical power of comparisons between clinical groups, and the size of confidence intervals around individual patient scores.
Manabu Kagami - One of the best experts on this subject based on the ideXlab platform.
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system design and performance characterization of a mems based laser scanning time of flight sensor based on a 256 times 64 pixel single photon imager
IEEE Photonics Journal, 2013Co-Authors: Cristiano Niclass, Isao Aoyagi, Hiroyuki Matsubara, Mineki Soga, Satoru Kato, Mitsutoshi Maeda, Manabu KagamiAbstract:This paper reports on a light detection and ranging (LIDAR) system that incorporates a microelectromechanical-system (MEMS) mirror scanner and a single-photon imager. The proposed architecture enables a high signal-to-background ratio due to pixel-level synchronization of the single-photon imager and the MEMS mirror. It also allows the receiving optics to feature a large aperture, yet utilizing a small MEMS device. The MEMS actuator achieves a mechanical scanning amplitude of ±4° horizontally and ±3° vertically, while the field of view of the overall sensor is 45 by 110. Distance images were acquired outdoors in order to qualitatively evaluate our sensor imaging capabilities. Quantitative ranging performance characterization carried out under 10 klx of ambient light revealed a Precision of 14.5 cm throughout the distance range to 25 m, thus leading to a Relative Precision of 0.58%.
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system design and performance characterization of a mems based laser scanning time of flight sensor based on a 256 times 64 pixel single photon imager
IEEE Photonics Journal, 2013Co-Authors: Kota Ito, Cristiano Niclass, Isao Aoyagi, Hiroyuki Matsubara, Mineki Soga, Satoru Kato, Mitsutoshi Maeda, Manabu KagamiAbstract:This paper reports on a light detection and ranging (LIDAR) system that incorporates a microelectromechanical-system (MEMS) mirror scanner and a single-photon imager. The proposed architecture enables a high signal-to-background ratio due to pixel-level synchronization of the single-photon imager and the MEMS mirror. It also allows the receiving optics to feature a large aperture, yet utilizing a small MEMS device. The MEMS actuator achieves a mechanical scanning amplitude of ±4° horizontally and ±3° vertically, while the field of view of the overall sensor is 45 by 110. Distance images were acquired outdoors in order to qualitatively evaluate our sensor imaging capabilities. Quantitative ranging performance characterization carried out under 10 klx of ambient light revealed a Precision of 14.5 cm throughout the distance range to 25 m, thus leading to a Relative Precision of 0.58%.
Cristiano Niclass - One of the best experts on this subject based on the ideXlab platform.
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system design and performance characterization of a mems based laser scanning time of flight sensor based on a 256 times 64 pixel single photon imager
IEEE Photonics Journal, 2013Co-Authors: Cristiano Niclass, Isao Aoyagi, Hiroyuki Matsubara, Mineki Soga, Satoru Kato, Mitsutoshi Maeda, Manabu KagamiAbstract:This paper reports on a light detection and ranging (LIDAR) system that incorporates a microelectromechanical-system (MEMS) mirror scanner and a single-photon imager. The proposed architecture enables a high signal-to-background ratio due to pixel-level synchronization of the single-photon imager and the MEMS mirror. It also allows the receiving optics to feature a large aperture, yet utilizing a small MEMS device. The MEMS actuator achieves a mechanical scanning amplitude of ±4° horizontally and ±3° vertically, while the field of view of the overall sensor is 45 by 110. Distance images were acquired outdoors in order to qualitatively evaluate our sensor imaging capabilities. Quantitative ranging performance characterization carried out under 10 klx of ambient light revealed a Precision of 14.5 cm throughout the distance range to 25 m, thus leading to a Relative Precision of 0.58%.
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system design and performance characterization of a mems based laser scanning time of flight sensor based on a 256 times 64 pixel single photon imager
IEEE Photonics Journal, 2013Co-Authors: Kota Ito, Cristiano Niclass, Isao Aoyagi, Hiroyuki Matsubara, Mineki Soga, Satoru Kato, Mitsutoshi Maeda, Manabu KagamiAbstract:This paper reports on a light detection and ranging (LIDAR) system that incorporates a microelectromechanical-system (MEMS) mirror scanner and a single-photon imager. The proposed architecture enables a high signal-to-background ratio due to pixel-level synchronization of the single-photon imager and the MEMS mirror. It also allows the receiving optics to feature a large aperture, yet utilizing a small MEMS device. The MEMS actuator achieves a mechanical scanning amplitude of ±4° horizontally and ±3° vertically, while the field of view of the overall sensor is 45 by 110. Distance images were acquired outdoors in order to qualitatively evaluate our sensor imaging capabilities. Quantitative ranging performance characterization carried out under 10 klx of ambient light revealed a Precision of 14.5 cm throughout the distance range to 25 m, thus leading to a Relative Precision of 0.58%.
M Jeitler - One of the best experts on this subject based on the ideXlab platform.
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Precision luminosity measurement in proton proton collisions at sqrt s 13 hbox tev s 13 tev in 2015 and 2016 at cms
European Physical Journal C, 2021Co-Authors: A M Sirunyan, A Tumasyan, W Adam, Janik Walter Andrejkovic, T Bergauer, S Chatterjee, M Dragicevic, Escalante A Del Valle, R Fruhwirth, M JeitlerAbstract:The measurement of the luminosity recorded by the CMS detector installed at LHC interaction point 5, using proton–proton collisions at $$\sqrt{s}=13\,{\text {TeV}} $$ in 2015 and 2016, is reported. The absolute luminosity scale is measured for individual bunch crossings using beam-separation scans (the van der Meer method), with a Relative Precision of 1.3 and 1.0% in 2015 and 2016, respectively. The dominant sources of uncertainty are related to residual differences between the measured beam positions and the ones provided by the operational settings of the LHC magnets, the factorizability of the proton bunch spatial density functions in the coordinates transverse to the beam direction, and the modeling of the effect of electromagnetic interactions among protons in the colliding bunches. When applying the van der Meer calibration to the entire run periods, the integrated luminosities when CMS was fully operational are 2.27 and 36.3 $$\,\text {fb}^{-1}$$ in 2015 and 2016, with a Relative Precision of 1.6 and 1.2%, respectively. These are among the most precise luminosity measurements at bunched-beam hadron colliders.
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Precision luminosity measurement in proton proton collisions at s 13tev in 2015 and 2016 at cms
European Physical Journal C, 2021Co-Authors: A M Sirunyan, A Tumasyan, W Adam, Janik Walter Andrejkovic, T Bergauer, S Chatterjee, M Dragicevic, Escalante A Del Valle, R Fruhwirth, M JeitlerAbstract:The measurement of the luminosity recorded by the CMS detector installed at LHC interaction point 5, using proton–proton collisions at $$\sqrt{s}=13\,{\text {TeV}} $$ in 2015 and 2016, is reported. The absolute luminosity scale is measured for individual bunch crossings using beam-separation scans (the van der Meer method), with a Relative Precision of 1.3 and 1.0% in 2015 and 2016, respectively. The dominant sources of uncertainty are related to residual differences between the measured beam positions and the ones provided by the operational settings of the LHC magnets, the factorizability of the proton bunch spatial density functions in the coordinates transverse to the beam direction, and the modeling of the effect of electromagnetic interactions among protons in the colliding bunches. When applying the van der Meer calibration to the entire run periods, the integrated luminosities when CMS was fully operational are 2.27 and 36.3 $$\,\text {fb}^{-1}$$ in 2015 and 2016, with a Relative Precision of 1.6 and 1.2%, respectively. These are among the most precise luminosity measurements at bunched-beam hadron colliders.
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Precision luminosity measurement in proton proton collisions at s 13tev in 2015 and 2016 at cms
European Physical Journal C, 2021Co-Authors: A M Sirunyan, A Tumasyan, W Adam, Janik Walter Andrejkovic, T Bergauer, S Chatterjee, M Dragicevic, Escalante A Del Valle, R Fruhwirth, M JeitlerAbstract:The measurement of the luminosity recorded by the CMS detector installed at LHC interaction point 5, using proton–proton collisions at s√=13TeV in 2015 and 2016, is reported. The absolute luminosity scale is measured for individual bunch crossings using beam-separation scans (the van der Meer method), with a Relative Precision of 1.3 and 1.0% in 2015 and 2016, respectively. The dominant sources of uncertainty are related to residual differences between the measured beam positions and the ones provided by the operational settings of the LHC magnets, the factorizability of the proton bunch spatial density functions in the coordinates transverse to the beam direction, and the modeling of the effect of electromagnetic interactions among protons in the colliding bunches. When applying the van der Meer calibration to the entire run periods, the integrated luminosities when CMS was fully operational are 2.27 and 36.3 fb−1 in 2015 and 2016, with a Relative Precision of 1.6 and 1.2%, respectively. These are among the most precise luminosity measurements at bunched-beam hadron colliders.
