The Experts below are selected from a list of 288 Experts worldwide ranked by ideXlab platform
Magnus Johannesson - One of the best experts on this subject based on the ideXlab platform.
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The Validity of QALYs An Experimental Test of Constant Proportional Tradeoff and Utility Independence
Medical Decision Making, 1997Co-Authors: Han Bleichrodt, Magnus JohannessonAbstract:Pliskin, Shepard, and Weinstein identified three preference conditions that ensure that quality-adjusted life years (QALYs) represent preferences over gambles over chronic health profiles. This paper presents an Experimental Test of the descriptive validity of two of these preference assumptions: utility independence and constant proportional tradeoff. Eighty students at the Stockholm School of Economics and 92 students at Erasmus University Rotterdam participated in the experiment. The results of the ex periment support the descriptive validity of constant proportional tradeoff: both within groups and between groups constant proportional tradeoff could not be rejected. The results are less supportive of the descriptive validity of utility independence. Within- groups utility independence was rejected. Between-groups utility independence could not be rejected, but this may have been due to a lack of statistical power. Analysis of the individual responses revealed that without adjustment for imprecision of...
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the validity of qalys an Experimental Test of constant proportional tradeoff and utility independence
Medical Decision Making, 1997Co-Authors: Han Bleichrodt, Magnus JohannessonAbstract:Pliskin, Shepard, and Weinstein identified three preference conditions that ensure that quality-adjusted life years (QALYs) represent preferences over gambles over chronic health profiles. This paper presents an Experimental Test of the descriptive validity of two of these preference assumptions: utility independence and constant proportional tradeoff. Eighty students at the Stockholm School of Economics and 92 students at Erasmus University Rotterdam participated in the experiment. The results of the experiment support the descriptive validity of constant proportional tradeoff: both within groups and between groups constant proportional tradeoff could not be rejected. The results are less supportive of the descriptive validity of utility independence. Within-groups utility independence was rejected. Between-groups utility independence could not be rejected, but this may have been due to a lack of statistical power. Analysis of the individual responses revealed that without adjustment for imprecision of preference, 39 respondents (22.8%) satisfied constant proportional tradeoff. Twenty-three respondents (13.4%) satisfied utility independence without adjustment for imprecision of preference. However, because of the relative unfamiliarity of the respondents with both the health states to be evaluated and the methods of health-state-utility measurement, it is likely that the respondents' preferences were imprecise. Adjusted for imprecision of preference, the upper estimates of the proportions of respondents who satisfied constant proportional tradeoff and utility independence, respectively, were 90.1% (155 respondents) and 75.6% (130 respondents). Pliskin et al. further derived that if an individual's preferences satisfy both constant proportional tradeoff and utility independence, then these preferences can be represented by a more general, risk-adjusted QALY model. Without adjustment for imprecision of preference, ten respondents (5.8%) satisfied both constant proportional tradeoff and utility independence. Adjusted for imprecision of preference, the upper estimate of the proportion of respondents who satisfied both constant proportional tradeoff and utility independence was 68.6% (118 respondents). The results of this study indicate that constant proportional tradeoff holds approximately. The evidence is much weaker for utility independence, however. This has important implications for the use of QALY-type measures in medical decision making.
Han Bleichrodt - One of the best experts on this subject based on the ideXlab platform.
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An Experimental Test of reduction invariance
Journal of Mathematical Psychology, 2016Co-Authors: Ilke Aydogan, Han Bleichrodt, Yu GaoAbstract:Abstract Prelec’s (1998) compound-invariant family provides an appealing way to model probability weighting and is widely used in empirical studies. Prelec (1998) gave a behavioral foundation for this function, but, as pointed out by Luce (2001), Prelec’s condition is hard to Test empirically. Luce proposed a simpler condition, reduction invariance, to characterize Prelec’s weighting function that is easier to Test empirically. Luce pointed out that Testing this condition is an important open empirical problem. This paper follows up on Luce’s suggestion and performs an Experimental Test of reduction invariance. Our data support reduction invariance both at the aggregate level and at the individual level where reduction invariance was the dominant pattern. A special case of reduction invariance is reduction of compound gambles, which is often considered rational and which characterizes the power weighting function. Reduction of compound gambles was rejected at the aggregate level even though 60% of our subjects behaved in line with it.
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The Validity of QALYs An Experimental Test of Constant Proportional Tradeoff and Utility Independence
Medical Decision Making, 1997Co-Authors: Han Bleichrodt, Magnus JohannessonAbstract:Pliskin, Shepard, and Weinstein identified three preference conditions that ensure that quality-adjusted life years (QALYs) represent preferences over gambles over chronic health profiles. This paper presents an Experimental Test of the descriptive validity of two of these preference assumptions: utility independence and constant proportional tradeoff. Eighty students at the Stockholm School of Economics and 92 students at Erasmus University Rotterdam participated in the experiment. The results of the ex periment support the descriptive validity of constant proportional tradeoff: both within groups and between groups constant proportional tradeoff could not be rejected. The results are less supportive of the descriptive validity of utility independence. Within- groups utility independence was rejected. Between-groups utility independence could not be rejected, but this may have been due to a lack of statistical power. Analysis of the individual responses revealed that without adjustment for imprecision of...
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the validity of qalys an Experimental Test of constant proportional tradeoff and utility independence
Medical Decision Making, 1997Co-Authors: Han Bleichrodt, Magnus JohannessonAbstract:Pliskin, Shepard, and Weinstein identified three preference conditions that ensure that quality-adjusted life years (QALYs) represent preferences over gambles over chronic health profiles. This paper presents an Experimental Test of the descriptive validity of two of these preference assumptions: utility independence and constant proportional tradeoff. Eighty students at the Stockholm School of Economics and 92 students at Erasmus University Rotterdam participated in the experiment. The results of the experiment support the descriptive validity of constant proportional tradeoff: both within groups and between groups constant proportional tradeoff could not be rejected. The results are less supportive of the descriptive validity of utility independence. Within-groups utility independence was rejected. Between-groups utility independence could not be rejected, but this may have been due to a lack of statistical power. Analysis of the individual responses revealed that without adjustment for imprecision of preference, 39 respondents (22.8%) satisfied constant proportional tradeoff. Twenty-three respondents (13.4%) satisfied utility independence without adjustment for imprecision of preference. However, because of the relative unfamiliarity of the respondents with both the health states to be evaluated and the methods of health-state-utility measurement, it is likely that the respondents' preferences were imprecise. Adjusted for imprecision of preference, the upper estimates of the proportions of respondents who satisfied constant proportional tradeoff and utility independence, respectively, were 90.1% (155 respondents) and 75.6% (130 respondents). Pliskin et al. further derived that if an individual's preferences satisfy both constant proportional tradeoff and utility independence, then these preferences can be represented by a more general, risk-adjusted QALY model. Without adjustment for imprecision of preference, ten respondents (5.8%) satisfied both constant proportional tradeoff and utility independence. Adjusted for imprecision of preference, the upper estimate of the proportion of respondents who satisfied both constant proportional tradeoff and utility independence was 68.6% (118 respondents). The results of this study indicate that constant proportional tradeoff holds approximately. The evidence is much weaker for utility independence, however. This has important implications for the use of QALY-type measures in medical decision making.
Luming Duan - One of the best experts on this subject based on the ideXlab platform.
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Experimental Test of entangled histories
Annals of Physics, 2017Co-Authors: Jordan Cotler, P Y Hou, Luming Duan, Frank Wilczek, Zhangqi YinAbstract:Abstract Entangled histories arise when a system partially decoheres in such a way that its past cannot be described by a sequence of states, but rather a superposition of sequences of states. Such entangled histories have not been previously observed. We propose and demonstrate the first Experimental scheme to create entangled history states of the Greenberger–Horne–Zeilinger (GHZ) type. In our experiment, the polarization states of a single photon at three different times are prepared as a GHZ entangled history state. We define a GHZ functional which attains a maximum value 1 on the ideal GHZ entangled history state and is bounded above by 1 ∕ 16 for any three-time history state lacking tripartite entanglement. We have measured the GHZ functional on a state we have prepared Experimentally, yielding a value of 0 . 656 ± 0 . 005 , clearly demonstrating the contribution of entangled histories.
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Experimental Test of entangled histories
arXiv: Quantum Physics, 2016Co-Authors: Jordan Cotler, P Y Hou, Luming Duan, Frank Wilczek, Zhangqi YinAbstract:We propose and demonstrate Experimentally a scheme to create entangled history states of the Greenberger-Horne-Zeilinger (GHZ) type. In our experiment, the polarization states of a single photon at three different times are prepared as a GHZ entangled history state. We define a GHZ functional which attains a maximum value $1$ on the ideal GHZ entangled history state and is bounded above by $1/16$ for any three-time history state lacking tripartite entanglement. We have measured the GHZ functional on a state we have prepared Experimentally, yielding a value of $0.656\pm 0.005$, clearly demonstrating the contribution of entangled histories.
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state independent Experimental Test of quantum contextuality in an indivisible system
Physical Review Letters, 2012Co-Authors: Y Wang, Dongling Deng, X Y Chang, K Liu, P Y Hou, Haoxiang Yang, Luming DuanAbstract:We report the first state-independent Experimental Test of quantum contextuality on a single photonic qutrit (three-dimensional system), based on a recent theoretical proposal [Phys. Rev. Lett. 108, 030402 (2012)]. Our experiment spotlights quantum contextuality in its most basic form, in a way that is independent of either the state or the tensor product structure of the system.
Yuji Hasegawa - One of the best experts on this subject based on the ideXlab platform.
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Experimental Test of entropic noise disturbance uncertainty relations for spin 1 2 measurements
Physical Review Letters, 2015Co-Authors: Georg Sulyok, Stephan Sponar, Bulent Demirel, Francesco Buscemi, Michael J W Hall, Masanao Ozawa, Yuji HasegawaAbstract:Information-theoretic definitions for noise and disturbance in quantum measurements were given in [Phys. Rev. Lett. 112, 050401 (2014)] and a state-independent noise-disturbance uncertainty relation was obtained. Here, we derive a tight noise-disturbance uncertainty relation for complementary qubit observables and carry out an Experimental Test. Successive projective measurements on the neutron's spin-1/2 system, together with a correction procedure which reduces the disturbance, are performed. Our Experimental results saturate the tight noise-disturbance uncertainty relation for qubits when an optimal correction procedure is applied.
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Experimental Test of quantum contextuality in neutron interferometry
Physical Review Letters, 2009Co-Authors: Hannes Bartosik, J Klepp, Claus Schmitzer, Stephan Sponar, Adan Cabello, H Rauch, Yuji HasegawaAbstract:We performed an Experimental Test of the Kochen-Specker theorem based on an inequality derived from the Peres-Mermin proof, using spin-path (momentum) entanglement in a single neutron system. Following the strategy proposed by Cabello et al.[Phys. Rev. Lett. 100, 130404 (2008)], a Bell-like state was generated, and three expectation values were determined. The observed violation 2.291+-0.008not<=1 clearly shows that quantum mechanical predictions cannot be reproduced by noncontextual hidden-variable theories.
Dongling Deng - One of the best experts on this subject based on the ideXlab platform.
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state independent Experimental Test of quantum contextuality in an indivisible system
Physical Review Letters, 2012Co-Authors: Y Wang, Dongling Deng, X Y Chang, K Liu, P Y Hou, Haoxiang Yang, Luming DuanAbstract:We report the first state-independent Experimental Test of quantum contextuality on a single photonic qutrit (three-dimensional system), based on a recent theoretical proposal [Phys. Rev. Lett. 108, 030402 (2012)]. Our experiment spotlights quantum contextuality in its most basic form, in a way that is independent of either the state or the tensor product structure of the system.
